amyloid A4; amyloid A4 precursor of Alzheimers disease

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153    52 GTGFAVAEPQIAMFCGKLNMHVNIQTGKWEPDPTGTKSCFETKEEVLQYCQEMYPELQITNVMEANQRVSIDNWCRRDKK 131
Cdd:smart00006   1 GAAGALAEPQIAMLCGRLNMHMNVQTGRWETDPSRTKTCLRDKEDILQYCRKAYPELQITNVVEASQPVTIQNWCRRGRS 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153   132 QCKS--RFVTPFKCLVGEFVSDVLLVPEKCQFFHKERMEVCENHQHWHTVVKEACLTQGMTLYSYGMLLPCGVDQFHGTE 209
Cdd:smart00006  81 QCKThhHFVIPFRCLVGEFVSDALLVPEGCQFLHQERMDQCETHQRWHQEAKEACSEKGMILHSFGMLLPCGIDKFRGVE 160

                   ....*
gi 343478153   210 YVCCP 214
Cdd:smart00006 161 FVCCP 165

juxtamembrane and transmembrane (JMTM) domain found in amyloid-like protein 2 (APLP-2) and similar proteins; Amyloid-like protein 2 (APLP-2), also called amyloid protein homolog (APPH), or CDEI box-binding protein (CDEBP), may play a role in the regulation of hemostasis. Its soluble form may have inhibitory properties towards coagulation factors. APLP-2 may bind to the DNA 5'-GTCACATG-3'(CDEI box). It inhibits trypsin, chymotrypsin, plasmin, factor XIA, and plasma and glandular kallikrein. This model corresponds to juxtamembrane and transmembrane (JMTM) domain of APLP-2, which consists of the intact transmembrane (TM) domain with adjacent N-terminal juxtamembrane (JM) region.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153 678 SVGPLREDFSLSSSALIGLLVIAVAIATVIVISLVMLRKRQYGTISHGIVEVDPMLTPEERHLNKMQNHGYENPTYKYLE 757
Cdd:cd21709    1 SDGPLRDDFSFSSSALIGLLVIAVAIATVIVISLVLLRKRQYGTISHGIVEVDPMLTPEERHLNKMQNHGYENPTYKYLE 80

                 .
gi 343478153 758 Q 758
Cdd:cd21709   81 Q 81

amyloid A4; amyloid A4 precursor of Alzheimers disease

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153    52 GTGFAVAEPQIAMFCGKLNMHVNIQTGKWEPDPTGTKSCFETKEEVLQYCQEMYPELQITNVMEANQRVSIDNWCRRDKK 131
Cdd:smart00006   1 GAAGALAEPQIAMLCGRLNMHMNVQTGRWETDPSRTKTCLRDKEDILQYCRKAYPELQITNVVEASQPVTIQNWCRRGRS 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153   132 QCKS--RFVTPFKCLVGEFVSDVLLVPEKCQFFHKERMEVCENHQHWHTVVKEACLTQGMTLYSYGMLLPCGVDQFHGTE 209
Cdd:smart00006  81 QCKThhHFVIPFRCLVGEFVSDALLVPEGCQFLHQERMDQCETHQRWHQEAKEACSEKGMILHSFGMLLPCGIDKFRGVE 160

                   ....*
gi 343478153   210 YVCCP 214
Cdd:smart00006 161 FVCCP 165

Amyloid A4 N-terminal heparin-binding; This N-terminal domain of APP, amyloid precursor protein, is the heparin-binding domain of the protein. this region is also responsible for stimulation of neurite outgrowth. The structure reveals both a highly charged basic surface that may interact with glycosaminoglycans in the brain and an abutting hydrophobic surface that is proposed to play an important functional role such as in dimerization or ligand-binding. Structural similarities with cysteine-rich growth factors, taken together with its known growth-promoting properties, suggest the APP N-terminal domain could function as a growth factor in vivo.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153   59 EPQIAMFCGKLNMHVNIQTGKWEPDPTGTKSCFETKEEVLQYCQEMYPELQITNVMEANQRVSIDNWCRRDKKQCK-SRF 137
Cdd:pfam02177   1 EPQVAMFCGKLNQHMDLETGRWEPDPSGKATCFKDKEEILDYCQKVYPELDITNIVEASQPVTIDNWCKKGRKKCKgHHI 80

                          90       100
                  ....*....|....*....|
gi 343478153  138 VTPFKCLVGEFVSDVLLVPE 157
Cdd:pfam02177  81 VKPYRCLVGEFVSDALLVPE 100

Kunitz domain found in the amyloid-beta precursor protein (ABPP) subfamily; This subfamily includes the amyloid-beta precursor protein (ABPP, also called APP, APPI, Alzheimer disease amyloid protein, amyloid-beta A4 protein, cerebral vascular amyloid peptide (CVAP), protease nexin II (PN2)), as well as amyloid-like protein 2 (APLP2, also called amyloid protein homolog or APPH), among others. ABPP/APPI is an inhibitor of serine proteases such as anionic and cationic trypsins. For example, APPI-4M is a variant that specifically inhibits Kallikrein (KLK)-related peptidase 6 (KLK6), which is highly upregulated in several types of cancer where its increased activity promotes cancer invasion and metastasis. Amyloid-like protein 2 (APLP2) inhibits trypsin, chymotrypsin, plasmin, factor XIA, and plasma and glandular kallikrein, and may play a role in the regulation of hemostasis. Proteins in this subfamily contain a single Kunitz domain, with a structure similar to those of other Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 343478153 319 VCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22607    1 VCSEQAETGPCRAMMPRWYFDVTEGKCAPFIYGGCGGNRNNFESEEYCMAVC 52

Kunitz/Bovine pancreatic trypsin inhibitor domain; Indicative of a protease inhibitor, usually a serine protease inhibitor. Structure is a disulfide rich alpha+beta fold. BPTI (bovine pancreatic trypsin inhibitor) is an extensively studied model structure. Certain family members are similar to the tick anticoagulant peptide (TAP). This is a highly selective inhibitor of factor Xa in the blood coagulation pathways. TAP molecules are highly dipolar, and are arranged to form a twisted two- stranded antiparallel beta-sheet followed by an alpha helix.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 343478153  319 VCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVCK 371
Cdd:pfam00014   1 ICSLPPDSGPCKASIPRWYYNPTTGTCEPFTYGGCGGNANNFESLEECESTCR 53

Chromosome segregation ATPase Smc [Cell cycle control, cell division, chromosome partitioning];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153 399 RFQKAKEQLEIRHRN----RMDRVKKEWEEAELQAknlpkAERQTLIQHFQAMVKALEKEAASEKQQLVETHLaRVEAML 474
Cdd:COG1196  214 RYRELKEELKELEAEllllKLRELEAELEELEAEL-----EELEAELEELEAELAELEAELEELRLELEELEL-ELEEAQ 287

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153 475 NDRRRmaLENYLAALQSDpprpHRILQALRRYVRAENKDRLHTIRHYQHVLAVDPEKAAQMKSQVMTHLHVIEERRNQSL 554
Cdd:COG1196  288 AEEYE--LLAELARLEQD----IARLEERRRELEERLEELEEELAELEEELEELEEELEELEEELEEAEEELEEAEAELA 361

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 343478153 555 SLLYKVPYVAQEIQEEIDELLQEQRADMDQFTASISE 591
Cdd:COG1196  362 EAEEALLEAEAELAEAEEELEELAEELLEALRAAAEL 398

amyloid A4; amyloid A4 precursor of Alzheimers disease

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153    52 GTGFAVAEPQIAMFCGKLNMHVNIQTGKWEPDPTGTKSCFETKEEVLQYCQEMYPELQITNVMEANQRVSIDNWCRRDKK 131
Cdd:smart00006   1 GAAGALAEPQIAMLCGRLNMHMNVQTGRWETDPSRTKTCLRDKEDILQYCRKAYPELQITNVVEASQPVTIQNWCRRGRS 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153   132 QCKS--RFVTPFKCLVGEFVSDVLLVPEKCQFFHKERMEVCENHQHWHTVVKEACLTQGMTLYSYGMLLPCGVDQFHGTE 209
Cdd:smart00006  81 QCKThhHFVIPFRCLVGEFVSDALLVPEGCQFLHQERMDQCETHQRWHQEAKEACSEKGMILHSFGMLLPCGIDKFRGVE 160

                   ....*
gi 343478153   210 YVCCP 214
Cdd:smart00006 161 FVCCP 165

Amyloid A4 N-terminal heparin-binding; This N-terminal domain of APP, amyloid precursor protein, is the heparin-binding domain of the protein. this region is also responsible for stimulation of neurite outgrowth. The structure reveals both a highly charged basic surface that may interact with glycosaminoglycans in the brain and an abutting hydrophobic surface that is proposed to play an important functional role such as in dimerization or ligand-binding. Structural similarities with cysteine-rich growth factors, taken together with its known growth-promoting properties, suggest the APP N-terminal domain could function as a growth factor in vivo.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153   59 EPQIAMFCGKLNMHVNIQTGKWEPDPTGTKSCFETKEEVLQYCQEMYPELQITNVMEANQRVSIDNWCRRDKKQCK-SRF 137
Cdd:pfam02177   1 EPQVAMFCGKLNQHMDLETGRWEPDPSGKATCFKDKEEILDYCQKVYPELDITNIVEASQPVTIDNWCKKGRKKCKgHHI 80

                          90       100
                  ....*....|....*....|
gi 343478153  138 VTPFKCLVGEFVSDVLLVPE 157
Cdd:pfam02177  81 VKPYRCLVGEFVSDALLVPE 100

juxtamembrane and transmembrane (JMTM) domain found in amyloid-like protein 1 (APLP-1) and similar proteins; Amyloid-like protein 1 (APLP-1), also called APLP, may play a role in postsynaptic function. It couples to JIP signal transduction through C-terminal binding. APLP-1 may interact with cellular G-protein signaling pathways. It can regulate neurite outgrowth through binding to components of the extracellular matrix such as heparin and collagen I. This model corresponds to the juxtamembrane and transmembrane (JMTM) domain of APLP-1, which consists of the intact transmembrane (TM) domain with adjacent N-terminal juxtamembrane (JM) region.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 343478153 687 SLSSSALIGLLVIAVAIATVIVISLVMLRKRQYGTISHGIVEVDPMLTPEERHLNKMQNHGYENPTYKYLEQ 758
Cdd:cd21708   14 TFNRGALIGLLVVAVAVAMVIVISLLLVRRKPYGTISHGIVEVDPMLTPEERQLSKMQNHGYENPTYRFLEE 85

Copper-binding of amyloid precursor, CuBD; This short domain, part of the extra-cellular N-terminus of the amyloid precursor protein, APP, can bind both copper and zinc, CuBD. The structure of Cu2+-bound CuBD reveals that the metal ligands are His147, His151, Tyr168 and two water molecules, which are arranged in a square pyramidal geometry. The structure of Cu+-bound CuBD is almost identical to the Cu2+-bound structure except for the loss of one of the water ligands. The geometry of the site is unfavourable for Cu+, thus providing a mechanism by which CuBD could readily transfer Cu ions to other proteins.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 343478153  159 CQFFHKERMEVCENHQHWHTVVKEACLTQGMTLYSYGMLLPCGVDQFHGTEYVCCP 214
Cdd:pfam12924   1 CKFDHKHNMDVCESHQHWHATAKEACAARGMVLHSFGMLLPCGIDLFTGVEFVCCP 56

Kunitz/Bovine pancreatic trypsin inhibitor domain; Indicative of a protease inhibitor, usually a serine protease inhibitor. Structure is a disulfide rich alpha+beta fold. BPTI (bovine pancreatic trypsin inhibitor) is an extensively studied model structure. Certain family members are similar to the tick anticoagulant peptide (TAP). This is a highly selective inhibitor of factor Xa in the blood coagulation pathways. TAP molecules are highly dipolar, and are arranged to form a twisted two- stranded antiparallel beta-sheet followed by an alpha helix.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 343478153  319 VCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVCK 371
Cdd:pfam00014   1 ICSLPPDSGPCKASIPRWYYNPTTGTCEPFTYGGCGGNANNFESLEECESTCR 53

Kunitz domain 2 of hepatocyte growth factor activator inhibitor-1 (HAI1); This model includes Kunitz domain 2 (KD2) of hepatocyte growth factor activator inhibitor type 1 (HAI-1 or HAI1, also known as Kunitz-type protease inhibitor 1), a membrane-bound multidomain protein essential to the integrity of the basement membrane during placental development. HAI-1 contains an extracellular region and several internal domains that include two Kunitz domains separated in sequence but spatially closed to each other, and their interdomain interactions have evolved to stimulate the inhibitory activity of an integrated Kunitz. While the Kunitz domain 1 (KD1) is the major inhibitory domain of HAI-1 and involved in auto-inhibition of the extracellular region via steric blockage of its active site in the HAI-1 compact tertiary structure, studies show that deletion of HAI-1 Kunitz domain 2 (KD2) and the extracellular region enhanced inhibition of matriptase. HAI-1 KD2 has been shown to have potent inhibitory activity against trypsin, but it cannot inhibit hepatocyte growth factor activator (HGFA), and matriptase. HAI-1 is also important in maintaining postnatal homeostasis in many tissues, including keratinization of the epidermis, hair development, colonic epithelium integrity, proliferation and cell fate of neural progenitor cells, and tissue injury and repair. The interaction between HAI-1 and matriptase is critical for tissue morphogenesis and cellular biology. HAI-1:matriptase ratio imbalance results in tumorigenesis; slight overexpression of matriptase relative to HAI-1 causes spontaneous squamous cell carcinoma, a phenotype that can be effectively reversed back to wild type by additional expression of HAI-1, indicating the need for a tight functional relationship between the two to maintain homeostasis. The structure of KD2 is similar to those of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVCK 371
Cdd:cd22624    2 CTEPPVTGPCRASFTRWYYDPLSRKCHRFTYGGCDGNENNFETEDECMETCS 53

Kunitz-type domain 2 (KD2) of hepatocyte growth factor activator inhibitor type 2 (HAI-2), and similar proteins; This model includes Kunitz domain 2 (KD2) of hepatocyte growth factor activator inhibitor type 2 (HAI-2 or HAI2, also known as placental bikunin or Kunitz-type protease inhibitor 2). HAI-2 is composed of two Kunitz domains that strongly inhibit many serine proteases with sub-nanomolar affinities. It has been found to be a natural tumor suppressor in renal cell carcinoma, breast cancer and prostate cancer, the loss of which leads to tumor growth and progression attributable at least in part to increased MET signaling. HAI-2 is a specific substrate of mesotrypsin which is up-regulated with progression in prostate cancers and shown to contribute to invasion and metastasis; these activities of mesotrypsin may in part be mediated through cleavage and inactivation of HAI-2, resulting in increases in hetatocyte growth factor/scatter factor (HGF/SF) activation and MET signaling. HAI-2 is a physiological inhibitor of hepsin and matriptase, two type II transmembrane serine proteases that, like HGF activator, can convert latent pro-HGF/SF into the two-chain active signaling heterodimer. KD2 is similar to KD1, whose structure is similar to those of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22622    3 CAAPRVTGPCRAAFPRWYYDPESQSCKEFIYGGCRGNKNNYLSEEECMDRC 53

Kunitz domain of papilin, and similar proteins; This model includes the Kunitz domain found in human and mouse papilin, and similar proteins. Papilin is an extracellular matrix glycoprotein that has been found in many organisms to be involved in thin matrix layers during gastrulation, matrix associated with wandering, phagocytic hemocytes, basement membranes and space-filling matrix during Drosophila development. It is a multidomain protein that primarily occurs in basement membranes. Papilins interact with several extracellular matrix components and ADAMTS enzymes, influences cell rearrangements and may modulate metalloproteinases during organogenesis. Papilins exist in mammals and invertebrates as a set of related, though not necessarily identical proteins. Mammalian papilin contains a single Kunitz domain, while other papilins such as that from Caenorhabditis elegans, contains multiple Kunitz domains. These domains are similar to Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor) that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 343478153 320 CSQEAMTG-PCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22635    1 CLLDKDAGtVCGDYVQRWYYDPATGACNRFWYGGCGGNANRFATEAECLRTC 52

Stichodactyla helianthus Kunitz inhibitor protein ShPI-1, Heteractis crispa protease inhibitor stichotoxin-Hcr2e, and similar proteins; This model includes Kunitz inhibitor protein ShPI-1, the major protease inhibitor from the sea anemone Stichodactyla helianthus, as well as protease inhibitor stichotoxin-Hcr2e (also called PI- stichotoxin-Hcr2e, PI-SHTX-Hcr2e, or Kunitz-type serine protease inhibitor InhVJ) and HCRG1 from Heteractis crispa. ShPI-1 has an unusually broad specificity toward several serine proteases, including trypsin, chymotrypsin, human neutrophil elastase, kallikrein and plasmin, and can also bind aspartic and cysteine proteases, such as pepsin and papain, respectively. PI-SHTX-Hcr2e and HCRG1 inhibit trypsin and chymotrypsin, but do not inhibit the serine proteases plasmin, thrombin, kallikrein, the cysteine proteinase papain, and the aspartic protease pepsin. The structures of these domains are similar to those of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 343478153 319 VCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVCK 371
Cdd:cd22618    1 ICSEPKVVGPCKAYFPRFYFDSETGKCTPFIYGGCGGNGNNFETLHACRAICR 53

Kunitz domain of epididymal protease inhibitor eppin and similar proteins; This subfamily includes the Kunitz inhibitor domain protein eppin (also called Cancer/testis antigen 71 or CT71, epididymal protease inhibitor, protease inhibitor WAP7, serine protease inhibitor-like with Kunitz and WAP domains 1, or WAP four-disulfide core domain protein 7) as well as WAP four-disulfide core domain proteins 6A and 6B in mice, and similar proteins. Eppin is a serine protease inhibitor that plays an essential role in male reproduction and fertility. It modulates the hydrolysis of seminal fluid protein semenogelin 1 (SEMG1) by the serine protease kallikrein-related peptidase 3 (KLK3, PSA), provides antimicrobial protection for spermatozoa in the ejaculate coagulum, and binds SEMG1, thereby inhibiting sperm motility. Thus, eppin could potentially be used as a target for male contraception. These domains are similar to Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor) that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 343478153 318 AVCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVCKA 372
Cdd:cd22611    1 DVCSLPKESGPCMAYFPRWWYDKETNTCSKFIYGGCQGNNNNFQSEAICQNICKK 55

Kunitz-type serine protease inhibitor 6 (BmTI-6), A (BmTI-A), and similar proteins; This group includes Kunitz-type serine protease inhibitors 6 (BmTI-6) and A (BmTI-A), both of which inhibit bovine trypsin, bovine chymotrypsin, human plasmin, human plasma kallikrein and human neutrophil elastase, but not bovine thrombin, human factor Xa or porcine pancreatic kallikrein. They may play a role in blocking blood coagulation during the larvae fixation on cattle. This subfamily also includes Rhipicephalus microplus protease inhibitor carrapatin. These proteins are similar to Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor) that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 343478153 319 VCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22604    5 QCSPTADSGPCFAYFPMWWYNVKTGQCEEFIYGGCQGNDNRYETEEECEKTC 56

bovine pancreatic trypsin inhibitor; This model contains bovine pancreatic trypsin inhibitor (BPTI, also known as pancreatic Kunitz inhibitor, aprotinin, or trypsin-kallikrein inhibitor), a small protein that inhibits the action of the trypsin, and is thus a member of the serine protease family of inhibitors. This class of enzymes contains conserved cysteine residues that form 3 disulfide bonds to stabilize the three-dimensional structure. BPTI has a relatively broad specificity, inhibiting trypsin as well as chymotrypsin, and elastase-like serine (pro)enzymes capable of very different primary specificity. It reacts rapidly with serine proteases to form stable complexes, but the enzyme:inhibitor complex formation may involve several intermediates corresponding to discrete reaction steps. Furthermore, BPTI inhibits the nitric oxide synthase type-I and -II action, and impairs K+ transport by Ca2+-activated K+ channels. Clinically, BPTI is used in certain surgical interventions, such as cardiopulmonary surgery and orthotopic liver transplantation since it significantly reduces hemorrhagic complications.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22592    2 CLEPPYTGPCKARIIRYFYNAKSGLCETFVYGGCRAKRNNFLSAEDCMRTC 52

Kunitz-type domain from the alpha3 chain of human type VI collagen, and similar proteins; This model includes the Kunitz-type domain from the alpha3 chain of type VI collagen (collagen alpha 3(VI) chain), encoded by COL6A3 gene. Collagen VI is a widely expressed member of the triple helix-containing protein superfamily of collagens and forms beaded microfibrils that anchor large interstitial structures. Immediately after fibril formation, the Kunitz domain can be cleaved off. Mutations in the alpha1, alpha2, and alpha3 chains of collagen VI cause myopathies ranging from the severe Ullrich congenital muscular dystrophy to the milder Bethlem myopathy, including intermediate forms. Early onset isolated dystonia, a neurological disease, has been shown to be caused by mutations in the alpha3 chain. Findings also indicated potential associations between COL6A3 polymorphisms and lung cancer risk. This domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 343478153 319 VCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22629    2 ICKLPKDEGTCRDFVLKWYYDPETKSCARFWYGGCGGNENRFDSQEECEKVC 53

Pseudocerastes persicus trypsin inhibitor (PPTI), Kunitz-type serine protease inhibitor bitisilin, and similar proteins; This group contains Pseudocerastes persicus trypsin inhibitor (PPTI), Bitis gabonica Kunitz-type serine protease inhibitor bitisilin-1 (BG-11), -2 (BG-15) and -3 (two-Kunitz protease inhibitor), Oxyuranus scutellatus scutellatus taicatoxin, and serine protease inhibitor component (TSPI, also called venom protease inhibitor 1 or venom protease inhibitor 2), among others. PPTI from P. persicus venom shows inhibitory effect against trypsin proteolytic activity and has similarities to dendrotoxins (DTXs), with corresponding functionally important residues. Studies have shown the ability of PPTI to inhibit voltage-gated potassium channels, and consequently have dual functionality. Bitilisins 1, 2, and 3 are serine protease inhibitors expressed in snake venom glands; bitsilin-3 consists of two Kunitz protease inhibitor domains. Taicatoxin inhibits trypsin, tissue kallikrein, elastase, plasmin and factor Xa, and is also known to block the voltage-dependent L-type calcium channels from the heart, and the small conductance calcium-activated potassium channels (KCa) in chromaffin cells and in the brain. The structures of these Kunitz-type proteins are similar to other Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22608    4 CYLPADPGPCKAYIPRFYYNSASNKCQQFIYGGCKGNANNFETKDECRYTC 54

second Kunitz domain of WAP, Kazal, immunoglobulin, Kunitz and NTR domain-containing proteins; This subfamily includes WAP, Kazal, immunoglobulin, Kunitz and NTR domain-containing protein 1 (WFIKKN1, WFKN1), WFIKKN2 (WFKN2), and similar proteins. WFIKKN proteins are protease inhibitors that contain two distinct Kunitz-type protease inhibitor domains. They may have serine protease- and metalloprotease-inhibitor activity. This model represents the second Kunitz (KU2) domain, which has been shown to inhibit trypsin, but not chymotrypsin, elastase, plasmin, pancreatic kallikrein, lung tryptase, plasma kallikrein, thrombin, urokinase or tissue plasminogen activator. However, the inhibition constant of this domain for bovine trypsin is about five orders of magnitudes lower than that of bovine pancreatic trypsin inhibitor (BPTI) for trypsin. This could be due to unfavorable side-chain conformation of a tryptophan at P2' site which is incompatible with a trypsin complex; typical trypsin inhibitors of the Kunitz family feature a tyrosine residue or other less bulky residues at this site. The structure of KU2 is similar to those of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 343478153 319 VCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22606    1 ICSLPAVQGPCKAWEPRWAYNSLLKQCQSFVYGGCEGNENNFESKEACEDAC 52

Kunitz-type domain from the alpha1 chain of type XXVIII collagen, and similar proteins; This model includes the Kunitz-type domain from the alpha1 chain of type XXVIII collagen (collagen alpha-1(XXVIII) chain) and similar proteins. The zebrafish has four collagen XXVIII genes all of which are differentially expressed in the liver, thymus, muscle, intestine and skin; only the alpha1 chain contains the Kunitz domain which is often proteolytically processed. Mammals only contain the alpha1 collagen chain, expressed mostly in dorsal root ganglia and peripheral nerves. The Kunitz domain is found at the C-terminus, and is most related to Kunitz domains of papilin and alpha3(VI) collagen. This domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor) that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22628    1 CLEPLDPGPCREYVVKWYYDKQANSCAQFWYGGCEGNRNRFETEEECRKTC 51

Kunitz-type domain from the alpha6 chain of human type VI collagen, and similar proteins; This model includes the Kunitz-type domain from the alpha6 chain of type VI collagen (collagen alpha 6(VI) chain), encoded by COL6A6 gene, and similar proteins. Collagen VI is a widely expressed member of the triple helix-containing protein superfamily of collagens and forms beaded microfibrils that anchor large interstitial structures. Immediately after fibril formation, the Kunitz domain can be cleaved off. This domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor) that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 343478153 319 VCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22630    2 ACSLDQDEGECQNYVLKWYYDQEQKECSQFWYGGCGGNKNRFETQEECEALC 53

conkunitzin-S1 and -S2, and similar proteins; This model includes Kunitz-type conkunitzin-S1 (Cs1) and -S2 (Cs2). Conkunitzins are pore-modulating toxins that block voltage-dependent potassium channels (Kvs) by exploiting inherent slow inactivation to block K+ channels. Cs1 binds to the channel turrets and disrupts the structural water hydrogen-bonding network, exposing the peripheral water pockets of ion channels and triggering an asymmetric collapse of the pore. Conus bullatus conkunitzin-B1, expressed in the venom duct, specifically blocks voltage-activated potassium channels (Kv) of the Shaker family. Members of this subfamily contain 2 disulfide bonds instead of the 3 present in most Kunitz domain proteins.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22593    1 CSLPLDEGSGNSSLTRWYYDPKKGQCKPFTYKGKGGNENNFLTKEDCEETC 51

Kunitz domain 1 (KD1) of tissue factor pathway inhibitor 2 (TFPI2) and similar proteins; This model represents the Kunitz-type domain 1 (KD1) of tissue factor pathway inhibitor 2 (TFPI2 or TFPI-2) and similar proteins. TFPI2 exhibits inhibitory activity primarily toward trypsin, plasmin, and factor VIIa (FVIIa)/tissue factor (TF) via its KD1. It is believed to be the major inhibitor of plasmin in the extracellular matrix (ECM) but has little inhibitory activity toward urokinase-type plasminogen activator, tissue-type plasminogen activator, or thrombin. TFPI2 specifically inhibits the proteases via the P1 arginine residue in KD1. The TFPI2 domains KD2 and KD3 appear to have no discernible inhibitory activity and may serve to bind to nearby proteins to localize TFPI2 in the ECM. Structure studies of KD1 complexed with proteases may help in the development of specific and potent KD1 domain protein that may have a large pharmacologic impact in preventing tumor metastasis, retinal degeneration, and degradation of collagen in the ECM. The structure of this domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 343478153 327 GPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22616   12 GPCRALIPRYYYDRYTQTCREFSYGGCEGNANNFESLEDCEKTC 55

early lactation protein (ELP), colostrum trypsin inhibitor (CTI), and similar proteins; This model includes the Kunitz-type proteins, colostrum trypsin inhibitor (CTI, also called colostrum BPI) and early lactation protein (ELP). In marsupials, the ELP gene is expressed in the mammary gland and the protein is secreted into milk during early lactation. Mature ELP shares approximately 55.4% similarity with the colostrum-specific bovine CTI protein. Marsupial ELP and eutherian CTI both have a single Kunitz domain and are secreted only during the early lactation phases, suggesting that this protein may have an important role in the immunologically immature young of these species. These proteins are similar to Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor) that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 343478153 318 AVCSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVCK 371
Cdd:cd22632    2 SLCQLPPARGPCRSNILRYFYNSTSRECEPFIYGGCNGNANNFETVEMCLRTCK 55

Kunitz protease inhibitor (KPI) domain 3 (KPI-3 or K3) of tissue factor pathway inhibitor (TFPI) and TFPI2, and similar proteins; This model represents the third Kunitz-type domain (K3 or KPI-3) of tissue factor pathway inhibitor (TFPI or TFPI1), also known as extrinsic pathway inhibitor (EPI) or lipoprotein-associated coagulation inhibitor (LACI), and of TFPI2 (or TFPI-2). TFPI1 down-regulates the extrinsic coagulation pathway via inhibition of activated factor X (FXa or Xa) and FVIIa (VIIa). It inhibits activated FXa via a "slow-tight binding mechanism", i.e. rapid formation of a loose FXa-TFPI1 complex that then slowly isomerizes to a tight FXa-TFPI1* complex. Subsequent inhibition of FVIIa is facilitated by the presence of tissue factor (TF) and FXa, which together rapidly and efficiently form a quaternary FXa-TFPI1-TF-FVIIa complex in which the activity of FXa and FVIIa are inhibited. TFPI1 consists of 3 Kunitz-type protease inhibitor (KPI) domains in a tandem arrangement; while the K1 domain of TFPI has been shown to bind and inhibit FVIIa and the K2 domain similarly inhibits FXa, the K3 domain has no known inhibitory function. However, Protein S, which functions as a cofactor for TFPI to efficiently enhance TFPI inhibition of FXa and FXa activated TF-VIIa, is dependent on direct interactions with two important residues within K3, a Glutamate and an Arginine. This model also includes TFPI2 Kunitz domain 3 (KD3). TFPI2 exhibits inhibitory activity primarily toward trypsin, plasmin, and factor VIIa (FVIIa)/tissue factor (TF) via its KD1. It is believed to be the major inhibitor of plasmin in the extracellular matrix (ECM) but has little inhibitory activity toward urokinase-type plasminogen activator, tissue-type plasminogen activator, or thrombin. While TFPI2 specifically inhibits the proteases via the P1 arginine residue in KD1, domains KD2 and KD3 appear to have no discernible inhibitory activity and may serve to bind to nearby proteins to localize TFPI2 in the ECM. The structure of this domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22615    4 CLSPKDEGLCSASVTRYYYNSATKTCEPFNYTGCGGNNNNFTSKKDCLRVC 54

Kunitz-type domain from the alpha6 chain of fish type VI collagen, and similar proteins; This model includes the Kunitz-type domain from the alpha6 chain of type VI collagen (collagen alpha 6(VI) chain) and similar proteins. Collagen VI is a widely expressed member of the triple helix-containing protein superfamily of collagens and forms beaded microfibrils that anchor large interstitial structures. Immediately after fibril formation, the Kunitz domain can be cleaved off. This domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor) that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22631    1 CLLGQDAGSCQNYTMMWFFDSKQGRCSRFWYGGCGGNANRFETQEECENLC 51

second Kunitz domain of Carboxypeptidase Inhibitor SmCI and similar domains; This group includes Sabellastarte magnifica carboxypeptidase inhibitor (SmCI), a tri-domain BPTI-Kunitz inhibitor capable of inhibiting serine proteases and A-like metallocarboxypeptidases. While the BPTI-Kunitz family of proteins includes voltage gated channel blockers and inhibitors of serine proteases, SmCI is the only BPTI-Kunitz protein capable of inhibiting metallocarboxypeptidases. Binding studies show that SmCI is able to bind three trypsin molecules under saturating conditions, but only one elastase interacts with the inhibitor. Additionally, SmCI can bind serine proteases and carboxypeptidases at the same time (at least in the ratio 1:1:1), thus becoming the first protease inhibitor that simultaneously blocks these two mechanistic classes of enzymes. This model contains the second Kunitz domain of SmCI, which has a structure similar to those of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22602    1 CSLPSKVGPCRVSARRWFHNPETEKCEVFIYGGCHGNANRFATETECQEVC 51

Kunitz protease inhibitor (KPI) domain 2 (KPI-2 or K2) of tissue factor pathway inhibitor (TFPI); This model represents the second Kunitz-type domain (K2 or KPI-2) of tissue factor pathway inhibitor (TFPI or TFPI1), also known as extrinsic pathway inhibitor (EPI) or lipoprotein-associated coagulation inhibitor (LACI). TFPI down-regulates the extrinsic coagulation pathway via inhibition of activated factor X (FXa or Xa) and FVIIa (VIIa). It inhibits activated FXa via a "slow-tight binding mechanism", i.e. rapid formation of a loose FXa-TFPI complex that then slowly isomerizes to a tight FXa-TFPI* complex. Subsequent inhibition of FVIIa is facilitated by the presence of tissue factor (TF) and FXa, which together rapidly and efficiently form a quaternary FXa-TFPI-TF-FVIIa complex in which the activity of FXa and FVIIa are inhibited. TFPI consists of 3 Kunitz-type protease inhibitor (KPI) domains in a tandem arrangement; the K2 domain is exposed on functionally active TFPI pools in circulation in blood, in platelets, and attached to the endothelium. While the K1 (or KPI-1) domain of TFPI has been shown to bind and inhibit FVIIa, the K2 domain inhibits FXa by binding directly to the active site and forming a FXa:TFPI complex. A close interaction between the TFPI K2 domain and the FXa active site is essential for the FXa inhibitory action of TFPI and for the formation of an inactive TF/FVIIa/FXa/TFPI complex which then prevents FXa generation. Thus, blockage of K2 would prevent TFPI binding to both FXa and FVIIa/TF, and fully abolish TFPI inhibition of the coagulation cascade. The structure of the K2 domain is similar to those of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22614    5 CFLEEDPGICRGLITRYFYNNQSKQCERFKYGGCLGNQNNFESLEECQNTC 55

first Kunitz domain of WAP, Kazal, immunoglobulin, Kunitz and NTR domain-containing proteins; This subfamily includes WAP, Kazal, immunoglobulin, Kunitz and NTR domain-containing protein 1 (WFIKKN1, WFKN1), WFIKKN2 (WFKN2), and similar proteins. WFIKKN proteins are protease inhibitors that contain two distinct Kunitz-type protease inhibitor domains. They may have serine protease- and metalloprotease-inhibitor activity. This model represents the first Kunitz domain that is similar to Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor) that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22605    2 CLKEPDREDCGEEQVRWYFDAKRGNCFTFTYGGCDGNRNHFETYEECRLAC 52

Kunitz-type domain from the alpha1 chain of type VII collagen, and similar proteins; This model includes the Kunitz-type domain from the alpha1 chain of type VII collagen (collagen alpha-1(VII) chain also called long-chain collagen or LC collagen) and similar proteins. LC collagen, encoded by the COL7A1 gene, is a stratified squamous epithelial basement membrane protein that forms anchoring fibrils which may contribute to epithelial basement membrane organization and adherence by interacting with extracellular matrix (ECM) proteins such as type IV collagen. So far, over 800 COL7A1 mutations have been reported, including missense, nonsense, splicing, insertion, and deletion mutations which to varying degrees leads to deficiency of type VII collagen. Epidermolysis bullosa acquisita (EBA) is an autoimmune acquired blistering skin disease resulting from autoantibodies to type VII collagen. The COL7A1 protein contains a Kunitz domain, the deactivation of which induces tumorigenesis. This domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22627    3 CLLPMDEGSCSDYTLLWYYHQKAGECRPFVYGGCGGNANRFSSKEDCELRC 53

juxtamembrane and transmembrane (JMTM) domain found in the amyloid-beta precursor protein (APP) family; The amyloid-beta precursor protein (APP) family includes amyloid-like proteins APLP-1 and APLP-2. APP (also called ABPP, APPI, Alzheimer disease (AD) amyloid protein, amyloid precursor protein, amyloid-beta A4 protein, cerebral vascular amyloid peptide (CVAP), PreA4, or protease nexin-II (PN-II)) functions as a cell surface receptor and performs physiological functions on the surface of neurons relevant to neurite growth, neuronal adhesion and axonogenesis. Amyloid-beta peptides are lipophilic metal chelators with metal-reducing activity; they bind transient metals such as copper, zinc and iron. APLP-1, also called APLP, may play a role in postsynaptic function. It couples to JIP signal transduction through C-terminal binding. APLP-1 may interact with cellular G-protein signaling pathways. It can regulate neurite outgrowth through binding to components of the extracellular matrix such as heparin and collagen I. APLP-2 (also called amyloid protein homolog (APPH), or CDEI box-binding protein (CDEBP)) may play a role in the regulation of hemostasis. Its soluble form may have inhibitory properties towards coagulation factors. APLP-2 may bind to the DNA 5'-GTCACATG-3'(CDEI box). It inhibits trypsin, chymotrypsin, plasmin, factor XIA, and plasma and glandular kallikrein. This model corresponds to juxtamembrane and transmembrane (JMTM) domain of APP, which consists of the intact transmembrane (TM) domain with adjacent N-terminal juxtamembrane (JM) region. More than half of all familial APP mutations of Alzheimer's disease are seen in its JMTM domain region.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 343478153 678 SVGPLREDFS-LSSSALIGLLVIAVAIATVIVISLVMLRKR 717
Cdd:cd21699    1 ERVFLAEDSSnSSFGAVIGLAVGGVAVAIVIVVAVVMLRRR 41

Kunitz-type serine protease inhibitor subunit of beta 2-bungarotoxin, and similar proteins; This model includes the Kunitz inhibitor subunit of beta 2-bungarotoxin, a presynaptic neurotoxin of the Bungarus multicinctus venom. Beta-bungarotoxin is a heterodimeric neurotoxin consisting of a phospholipase subunit linked by a disulfide bond to the Kunitz protease inhibitor subunit; the latter subunit is homologous to venom basic protease inhibitors but has no protease inhibitor activity and is non-toxic. The beta-bungarotoxin Kunitz subunit serves to guide the toxin to its site of action on the presynaptic membrane by virtue of a high-affinity interaction with a specific subclass of voltage-sensitive potassium channels. This subfamily also includes Kunitz-type serine protease inhibitor homolog beta-bungarotoxin B1 chain and protease inhibitor-like protein 1 (PILP-1). The B1 chain also has no protease inhibitor activity but blocks voltage-gated potassium channels, while PILP-1 inhibits trypsin. The structures of these domains are similar to those of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 343478153 320 CSQEAMTGPCRAVMPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22619    7 CDKPPDTKRCKRVVRAFYYNPSAKTCLQFVYGGCNGNGNHFKSKALCRCHC 57

juxtamembrane and transmembrane (JMTM) domain found in amyloid-beta precursor protein (APP) and similar proteins; Amyloid-beta precursor protein (APP), also called APPI, ABPP, Alzheimer disease amyloid protein, amyloid precursor protein, amyloid-beta A4 protein, cerebral vascular amyloid peptide (CVAP), PreA4, or protease nexin-II (PN-II), functions as a cell surface receptor and performs physiological functions on the surface of neurons relevant to neurite growth, neuronal adhesion and axonogenesis. Amyloid-beta peptides are lipophilic metal chelators with metal-reducing activity; they bind transient metals such as copper, zinc and iron. This model corresponds to juxtamembrane and transmembrane (JMTM) domain of APP, which consists of the intact transmembrane (TM) domain with adjacent N-terminal juxtamembrane (JM) region. More than half of all familial APP mutations of Alzheimer's disease are seen in its JMTM domain region.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 343478153 684 EDFSLSSSALIGLLVIAVAIATVIVISLVMLRKR 717
Cdd:cd21707    7 EDVGSNKGAIIGLMVGGVVIATVIVITLVMLKKK 40

Kunitz-type domain 1 (K1) of Ixolaris, and similar proteins; This model includes the first Kunitz-type domain (K1) of ixolaris from the venomous organism Conus striatus. Ixolaris is a potent tick salivary anticoagulant that binds coagulation factor Xa (FXa) and zymogen FX, and forms a quaternary tissue factor (TF)/FVIIa/FX(a)/Ixolaris inhibitory complex. It blocks TF-induced coagulation and PAR2 (proteinase-activated receptor 2) signaling, and prevents thrombosis, tumor growth, and immune activation. Ixolaris consists of 2 Kunitz domains (K1 and K2), both of which recognize the heparin-binding (pro)exosite (HBE) on FX. While K2 is an extraordinarily dynamic domain that encompasses several residues involved in FX binding, K1 domain keeps as a rigid platform supporting the conformational dynamic of the K2 domain, forming a salt bridge with FXa. The structure of this domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), showing an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.

                         10        20        30
                 ....*....|....*....|....*....|....*...
gi 343478153 333 MPRWYFDLSKGKCVRFIYGGCGGNRNNFESEDYCMAVC 370
Cdd:cd22625   16 TKRYGYNKKTQQCEEFLGTECGGGGNSFEEAKECWSSC 53

Lipopolysaccharide biosynthesis regulator YciM/LapB, contains six TPR domains and a C-terminal metal-binding domain [Cell wall/membrane/envelope biogenesis];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153 393 DDNEHARFQKAKEQLEirhRNRMDRVKKEWEEAELQAKNLPKAERQtLIQHFQAM---VKALE--KEAASEKQQLVETH- 466
Cdd:COG2956   73 PDRAEALLELAQDYLK---AGLLDRAEELLEKLLELDPDDAEALRL-LAEIYEQEgdwEKAIEvlERLLKLGPENAHAYc 148

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 343478153 467 -LARVeAMLNDRRRMALENYLAALQSDP--PRPHRILQALrrYVRAENKDRLhtIRHYQHVLAVDPEKAAQMKSqvMTHL 543
Cdd:COG2956  149 eLAEL-YLEQGDYDEAIEALEKALKLDPdcARALLLLAEL--YLEQGDYEEA--IAALERALEQDPDYLPALPR--LAEL 221

                        170       180       190
                 ....*....|....*....|....*....|..
gi 343478153 544 HVIEERRNQSLSLLYKvpyvAQEIQEEIDELL 575
Cdd:COG2956  222 YEKLGDPEEALELLRK----ALELDPSDDLLL 249