C-terminal catalytic domain of the oxygenase alpha subunit of Pseudomonas resinovorans strain CA10 anthranilate 1,2-dioxygenase and related aromatic ring hydroxylating dioxygenases; C-terminal catalytic domain of the oxygenase alpha subunit of anthranilate 1,2-dioxygenase (AntDO) and related Rieske-type non-heme iron aromatic ring-hydroxylating oxygenases (RHOs, also known as aromatic ring hydroxylating dioxygenases). RHOs utilize non-heme Fe(II) to catalyze the addition of hydroxyl groups to the aromatic ring, an initial step in the oxidative degradation of aromatic compounds. RHOs are composed of either two or three protein components, and are comprised of an electron transport chain (ETC) and an oxygenase. The ETC transfers reducing equivalents from the electron donor to the oxygenase component, which in turn transfers electrons to the oxygen molecules. The oxygenase components are oligomers, either (alpha)n or (alpha)n(beta)n. The alpha subunits are the catalytic components and have an N-terminal domain, which binds a Rieske-like 2Fe-2S cluster, and the C-terminal catalytic domain which binds the non-heme Fe(II). The Fe(II) is co-ordinated by conserved His and Asp residues. Oxygenases belonging to this subgroup include the alpha subunits of AntDO, aniline dioxygenase, Acinetobacter calcoaceticus benzoate 1,2-dioxygenase, 2-halobenzoate 1,2-dioxygenase from Pseudomonas cepacia 2CBS, 2,4,5-trichlorophenoxyacetic acid oxygenase from Pseudomonas cepacia AC1100, 2,4-dichlorophenoxyacetic acid oxygenase from Bradyrhizobium sp. strain HW13, p-cumate 2,3-dioxygenase, 2-halobenzoate 1,2-dioxygenase form Pseudomonas cepacia 2CBS, and Pseudomonas putida IacC, which may be involved in the catabolism of the plant hormone indole 3-acetic acid. This subfamily belongs to the SRPBCC (START/RHO_alpha_C/PITP/Bet_v1/CoxG/CalC) domain superfamily of proteins that bind hydrophobic ligands. SRPBCC domains have a deep hydrophobic ligand-binding pocket.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 190 SGQQDYAIRANWKLLVENSNDGYHAAMTHATYLDYL----ANTHAKG----NEVALKGVGRELGGGHAVVEYTAPWGRPI 261
Cdd:cd08879     1 GGTHRYRYRGNWKLQLENGTDGYHPPFVHASYVATTgaaaADATRGGlssfMTGPQGGGVRDLGNGHSVLDSRPEIPRLD 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 262 AnwipvwgEEGKVEMDRIHARLEQEHGKAKADRI-CFKNRNLLIFPNLVINDIMAvTFRTFYPLAPNYMNVSGWALAP-- 338
Cdd:cd08879    81 A-------DRPKPPIAEYRAALVAAHGEERARRIlRGRGRNLNIFPNLFIIDISQ-QIRVIRPIAVDETEVTSWALRPkg 152

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 339 TNETEWARKYRLNNFLEFlgPGGFATPDDVEALESCQAGYANsleSGAEWNDISKGMGMD---------AMYDDEIQMRS 409
Cdd:cd08879   153 APDEVNRRRLRYSEDFFG--PSGFATPDDLEAFERCQRGLAA---RGEEWVDLSRGLGREkadedgvvtGAVTDELPMRN 227

                         250
                  ....*....|
gi 1308985318 410 FWKEWNRRVQ 419
Cdd:cd08879   228 QWRAWKRLMT 237

pheophorbide a oxygenase

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1308985318  67 RNLIFNRD-STGKVNAFFNTCPHRGAEVCREAKGNSKHFTCMYHGWIFSADGELKNLP 123
Cdd:PLN02518  113 RDLVLWKDpNQGEWVAFDDKCPHRLAPLSEGRIDENGHLQCSYHGWSFDGCGSCTRIP 170

C-terminal catalytic domain of the oxygenase alpha subunit of Pseudomonas resinovorans strain CA10 anthranilate 1,2-dioxygenase and related aromatic ring hydroxylating dioxygenases; C-terminal catalytic domain of the oxygenase alpha subunit of anthranilate 1,2-dioxygenase (AntDO) and related Rieske-type non-heme iron aromatic ring-hydroxylating oxygenases (RHOs, also known as aromatic ring hydroxylating dioxygenases). RHOs utilize non-heme Fe(II) to catalyze the addition of hydroxyl groups to the aromatic ring, an initial step in the oxidative degradation of aromatic compounds. RHOs are composed of either two or three protein components, and are comprised of an electron transport chain (ETC) and an oxygenase. The ETC transfers reducing equivalents from the electron donor to the oxygenase component, which in turn transfers electrons to the oxygen molecules. The oxygenase components are oligomers, either (alpha)n or (alpha)n(beta)n. The alpha subunits are the catalytic components and have an N-terminal domain, which binds a Rieske-like 2Fe-2S cluster, and the C-terminal catalytic domain which binds the non-heme Fe(II). The Fe(II) is co-ordinated by conserved His and Asp residues. Oxygenases belonging to this subgroup include the alpha subunits of AntDO, aniline dioxygenase, Acinetobacter calcoaceticus benzoate 1,2-dioxygenase, 2-halobenzoate 1,2-dioxygenase from Pseudomonas cepacia 2CBS, 2,4,5-trichlorophenoxyacetic acid oxygenase from Pseudomonas cepacia AC1100, 2,4-dichlorophenoxyacetic acid oxygenase from Bradyrhizobium sp. strain HW13, p-cumate 2,3-dioxygenase, 2-halobenzoate 1,2-dioxygenase form Pseudomonas cepacia 2CBS, and Pseudomonas putida IacC, which may be involved in the catabolism of the plant hormone indole 3-acetic acid. This subfamily belongs to the SRPBCC (START/RHO_alpha_C/PITP/Bet_v1/CoxG/CalC) domain superfamily of proteins that bind hydrophobic ligands. SRPBCC domains have a deep hydrophobic ligand-binding pocket.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 190 SGQQDYAIRANWKLLVENSNDGYHAAMTHATYLDYL----ANTHAKG----NEVALKGVGRELGGGHAVVEYTAPWGRPI 261
Cdd:cd08879     1 GGTHRYRYRGNWKLQLENGTDGYHPPFVHASYVATTgaaaADATRGGlssfMTGPQGGGVRDLGNGHSVLDSRPEIPRLD 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 262 AnwipvwgEEGKVEMDRIHARLEQEHGKAKADRI-CFKNRNLLIFPNLVINDIMAvTFRTFYPLAPNYMNVSGWALAP-- 338
Cdd:cd08879    81 A-------DRPKPPIAEYRAALVAAHGEERARRIlRGRGRNLNIFPNLFIIDISQ-QIRVIRPIAVDETEVTSWALRPkg 152

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 339 TNETEWARKYRLNNFLEFlgPGGFATPDDVEALESCQAGYANsleSGAEWNDISKGMGMD---------AMYDDEIQMRS 409
Cdd:cd08879   153 APDEVNRRRLRYSEDFFG--PSGFATPDDLEAFERCQRGLAA---RGEEWVDLSRGLGREkadedgvvtGAVTDELPMRN 227

                         250
                  ....*....|
gi 1308985318 410 FWKEWNRRVQ 419
Cdd:cd08879   228 QWRAWKRLMT 237

Rieske non-heme iron oxygenase (RO) family, N-terminal Rieske domain of the oxygenase alpha subunit; The RO family comprise a large class of aromatic ring-hydroxylating dioxygenases found predominantly in microorganisms. These enzymes enable microorganisms to tolerate and even exclusively utilize aromatic compounds for growth. ROs consist of two or three components: reductase, oxygenase, and ferredoxin (in some cases) components. The oxygenase component may contain alpha and beta subunits, with the beta subunit having a purely structural function. Some oxygenase components contain only an alpha subunit. The oxygenase alpha subunit has two domains, an N-terminal Rieske domain with an [2Fe-2S] cluster and a C-terminal catalytic domain with a mononuclear Fe(II) binding site. The Rieske [2Fe-2S] cluster accepts electrons from the reductase or ferredoxin component and transfers them to the mononuclear iron for catalysis. Reduced pyridine nucleotide is used as the initial source of two electrons for dioxygen activation.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318  44 WLYVGHESEVAKKGDFVRRIVAKRNLIFNRDSTGKVNAFFNTCPHRGAEVCREAKGNSKHFTCMYHGWIFSADGELKNLP 123
Cdd:cd03469     1 WYFVGHSSELPEPGDYVTLELGGEPLVLVRDRDGEVRAFHNVCPHRGARLCEGRGGNAGRLVCPYHGWTYDLDGKLVGVP 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|.
gi 1308985318 124 GSERYSADFKEQKRgnLVPVPrFENYRGVCFVNFDPNACSL 164
Cdd:cd03469    81 REEGFPGFDKEKLG--LRTVP-VEEWGGLIFVNLDPDAPPL 118

Rieske non-heme iron oxygenase (RO) family, Ortho-halobenzoate-1,2-dioxygenase (OHBDO)-like subfamily, N-terminal Rieske domain of the oxygenase alpha subunit; composed of the oxygenase alpha subunits of OHBDO, salicylate 5-hydroxylase (S5H), terephthalate 1,2-dioxygenase system (TERDOS) and similar proteins. ROs comprise a large class of aromatic ring-hydroxylating dioxygenases that enable microorganisms to tolerate and utilize aromatic compounds for growth. The oxygenase alpha subunit contains an N-terminal Rieske domain with an [2Fe-2S] cluster and a C-terminal catalytic domain with a mononuclear Fe(II) binding site. The Rieske [2Fe-2S] cluster accepts electrons from a reductase or ferredoxin component and transfers them to the mononuclear iron for catalysis. OHBDO converts 2-chlorobenzoate (2-CBA) to catechol as well as 2,4-dCBA and 2,5-dCBA to 4-chlorocatechol, as part of the chlorobenzoate degradation pathway. Although ortho-substituted chlorobenzoates appear to be particularly recalcitrant to biodegradation, several strains utilize 2-CBA and the dCBA derivatives as a sole carbon and energy source. S5H converts salicylate (2-hydroxybenzoate), a metabolic intermediate of phenanthrene, to gentisate (2,5-dihydroxybenzoate) as part of an alternate pathway for naphthalene catabolism. S5H is a multicomponent enzyme made up of NagGH (the oxygenase components), NagAa (the ferredoxin reductase component), and NagAb (the ferredoxin component). The oxygenase component is made up of alpha (NagG) and beta (NagH) subunits. TERDOS is present in gram-positive bacteria and proteobacteria where it converts terephthalate (1,4-dicarboxybenzene) to protocatechuate as part of the terephthalate degradation pathway. The oxygenase component of TERDOS, called TerZ, is a hetero-hexamer with 3 alpha (TerZalpha) and 3 beta (TerZbeta) subunits.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318  20 RVARKAFTDSEIIKAEYEEVFN-KCWLYVGHESEVAKKGDFVRRIVAKRNLIFNRDSTGKVNAFFNTCPHRGAEVCREAK 98
Cdd:cd03545     1 RVPYKVFTDRAYFDREQERIFRgKTWSYVGLEAEIPNAGDFKSTFVGDTPVVVTRAEDGSLHAWVNRCAHRGALVCRERR 80

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1308985318  99 GNSKHFTCMYHGWIFSADGELKNLP------GSERYSADFkEQKRGNLVPVpRFENYRGVCFVNFDPNACSL 164
Cdd:cd03545    81 GNDGSLTCVYHQWAYDLKGNLKGVPfrrglkGQGGMPKDF-DMKQHGLEKL-RVETVGGLVFASFSDEVEPL 150

Rieske non-heme iron oxygenase (RO) family, Biphenyl dioxygenase (BPDO)-like subfamily, N-terminal Rieske domain of the oxygenase alpha subunit; composed of the oxygenase alpha subunits of BPDO and similar proteins including cumene dioxygenase (CumDO), nitrobenzene dioxygenase (NBDO), alkylbenzene dioxygenase (AkbDO) and dibenzofuran 4,4a-dioxygenase (DFDO). ROs comprise a large class of aromatic ring-hydroxylating dioxygenases that enable microorganisms to tolerate and utilize aromatic compounds for growth. The oxygenase alpha subunit contains an N-terminal Rieske domain with an [2Fe-2S] cluster and a C-terminal catalytic domain with a mononuclear Fe(II) binding site. The Rieske [2Fe-2S] cluster accepts electrons from a reductase or ferredoxin component and transfers them to the mononuclear iron for catalysis. BPDO degrades biphenyls and polychlorinated biphenyls (PCB's) while CumDO degrades cumene (isopropylbenzene), an aromatic hydrocarbon that is intermediate in size between ethylbenzene and biphenyl. NBDO catalyzes the initial reaction in nitrobenzene degradation, oxidizing the aromatic rings of mono- and dinitrotoluenes to form catechol and nitrite. NBDO belongs to the naphthalene subfamily of ROs. AkbDO is involved in alkylbenzene catabolism, converting o-xylene to 2,3- and 3,4-dimethylphenol and ethylbenzene to cis-dihydrodiol. DFDO is involved in dibenzofuran degradation.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318  37 EEVFNKCWLYVGHESEVAKKGDFVRRIVAKRNLIFNRDSTGKVNAFFNTCPHRGAEVCREAKGNSKHFTCMYHGWIFSAD 116
Cdd:cd03472     2 ERVFARSWLLLGHETHIPKAGDYLTTYMGEDPVIVVRQKDGSIRVFLNQCRHRGMRICRSDAGNAKAFTCTYHGWAYDTA 81

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*....
gi 1308985318 117 GELKNLP-GSERYSADFKEQKRGNLvpVPRFENYRGVCFVNFDPNACSL 164
Cdd:cd03472    82 GNLVNVPfEKEAFCDGLDKADWGPL--QARVETYKGLIFANWDAEAPDL 128

Rieske [2Fe-2S] domain; The rieske domain has a [2Fe-2S] centre. Two conserved cysteines coordinate one Fe ion, while the other Fe ion is coordinated by two conserved histidines. In hyperthermophilic archaea there is a SKTPCX(2-3)C motif at the C-terminus. The cysteines in this motif form a disulphide bridge, which stabilizes the protein.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318  43 CWLYVGHESEVAKKGDFVRRIVAKrNLIFNRDSTGKVNAFFNTCPHRGAEVCrEAKGNSK-HFTCMYHGWIFSADGELKN 121
Cdd:pfam00355   1 SWYPVCHSSELPEGEPKVVEVGGE-PLVVFRDEDGELYALEDRCPHRGAPLS-EGKVNGGgRLECPYHGWRFDGTGKVVK 78

                  ...
gi 1308985318 122 LPG 124
Cdd:pfam00355  79 VPA 81

C-terminal catalytic domain of the oxygenase alpha subunit of naphthalene 1,2-dioxygenase (NDO) and related aromatic ring hydroxylating dioxygenases; C-terminal catalytic domain of the oxygenase alpha subunit of naphthalene 1,2-dioxygenase (NDO) and related Rieske-type non-heme iron aromatic ring-hydroxylating oxygenases (RHOs, also known as aromatic ring hydroxylating dioxygenases). This domain binds non-heme Fe(II). RHOs utilize non-heme Fe(II) to catalyze the addition of hydroxyl groups to the aromatic ring, an initial step in the oxidative degradation of aromatic compounds. RHOs are composed of either two or three protein components, and are comprised of an electron transport chain (ETC) and an oxygenase. The ETC transfers reducing equivalents form the electron donor to the oxygenase component, which in turn transfers electrons to the oxygen molecules. The oxygenase components are oligomers, either (alpha)n or (alpha)n(beta)n. The alpha subunits are the catalytic components and have an N-terminal domain, which binds a Rieske-like 2Fe-2S cluster, and a C-terminal domain which binds the non-heme Fe(II). The Fe(II) is co-ordinated by conserved His and Asp residues. Proteins belonging to this subgroup include the terminal oxygenase alpha subunits of biphenyl dioxygenase, cumene dioxygenase from Pseudomonas fluorescens IP01, ethylbenzene dioxygenase, naphthalene 1,2-dioxygenase, nitrobenzene dioxygenase from Comamonas sp. strain JS765, toluene 2,3-dioxygenase from Pseudomonas putida F1, dioxin dioxygenase of Sphingomonas sp. Strain RW1, and the polycyclic aromatic hydrocarbons (PAHs)degrading ring-hydroxylating dioxygenase from Sphingomonas CHY-1. This subfamily belongs to the SRPBCC (START/RHO_alpha_C/PITP/Bet_v1/CoxG/CalC) domain superfamily of proteins that bind hydrophobic ligands. SRPBCC domains have a deep hydrophobic ligand-binding pocket.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 185 GMTIVSGQQDYAIRANWKLLVENS-NDGYHAAMTHATYLDYLANTHAKGNEVALKGVG-RELGGGHAVveytapwgrpIA 262
Cdd:cd08881     1 GLEVVGGPQKWVIKANWKLAAENFaGDGYHTGTTHASALEAGLPPDAADLPPIDLGLQfTAPWHGHGL----------GF 70

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 263 NWIPVWgeegkvemdriharleqeHGkakadricfknrnlLIFPNLVINDIMAVTFRTFYPLAPNYMNVSGWALAPTNET 342
Cdd:cd08881    71 FLDSPQ------------------HG--------------TIFPNLSFLPGYFNTLRVWHPRGPDETEVWTWTLVDKDAP 118

                         170       180       190
                  ....*....|....*....|....*....|....*.
gi 1308985318 343 -EWARKYRLNNFLEFlGPGGFATPDDVEALESCQAG 377
Cdd:cd08881   119 eEVKDRVRRQYTRTF-GPAGTFEQDDGENWEEITRV 153

Rieske domain; a [2Fe-2S] cluster binding domain commonly found in Rieske non-heme iron oxygenase (RO) systems such as naphthalene and biphenyl dioxygenases, as well as in plant/cyanobacterial chloroplast b6f and mitochondrial cytochrome bc(1) complexes. The Rieske domain can be divided into two subdomains, with an incomplete six-stranded, antiparallel beta-barrel at one end, and an iron-sulfur cluster binding subdomain at the other. The Rieske iron-sulfur center contains a [2Fe-2S] cluster, which is involved in electron transfer, and is liganded to two histidine and two cysteine residues present in conserved sequences called Rieske motifs. In RO systems, the N-terminal Rieske domain of the alpha subunit acts as an electron shuttle that accepts electrons from a reductase or ferredoxin component and transfers them to the mononuclear iron in the alpha subunit C-terminal domain to be used for catalysis.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1308985318  44 WLYVGHESEVaKKGDFVRRIVAKRNLIFNRDSTGKVNAFFNTCPHRGAEVCrEAKGNSKHFTCMYHGWIFS-ADGELK 120
Cdd:cd03467     1 WVVVGALSEL-PPGGGRVVVVGGGPVVVVRREGGEVYALSNRCTHQGCPLS-EGEGEDGCIVCPCHGSRFDlRTGEVV 76

Rieske non-heme iron oxygenase (RO) family, Choline monooxygenase (CMO) subfamily, N-terminal Rieske domain of the oxygenase alpha subunit; ROs comprise a large class of aromatic ring-hydroxylating dioxygenases that enable microorganisms to tolerate and utilize aromatic compounds for growth. The oxygenase alpha subunit contains an N-terminal Rieske domain with an [2Fe-2S] cluster and a C-terminal catalytic domain with a mononuclear Fe(II) binding site. The Rieske [2Fe-2S] cluster accepts electrons from a reductase or ferredoxin component and transfers them to the mononuclear iron for catalysis. CMO is a novel RO found in certain plants which catalyzes the first step in betaine synthesis. CMO is not found in animals or bacteria. In these organisms, the first step in betaine synthesis is catalyzed by either the membrane-bound choline dehydrogenase (CDH) or the soluble choline oxidase (COX).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1308985318  44 WLYVGHESEVAKKGDFVRRIVAKRNLIFNRDSTGKVNAFFNTCPHRgAEVCREAKGNSKHFTCMYHGWIFSADGEL 119
Cdd:cd03541     2 WQVAGYSDQVKEKNQYFTGRLGNVEYVVCRDGNGKLHAFHNVCTHR-ASILACGSGKKSCFVCPYHGWVYGLDGSL 76

C-terminal catalytic domain of the large/alpha subunit (ahdA1c) of a ring-hydroxylating dioxygenase from Sphingomonas sp. strain P2 and related proteins; C-terminal catalytic domain of the large subunit (ahdA1c) of the AhdA3A4A2cA1c salicylate 1-hydroxylase complex from Sphingomonas sp. strain P2, and related Rieske-type non-heme iron aromatic ring-hydroxylating oxygenases (RHOs, also known as aromatic ring hydroxylating dioxygenases). AhdA3A4A2cA1c is one of three known isofunctional salicylate 1-hydroxylase complexes in strain P2, involved in phenanthrene degradation, which catalyze the monooxygenation of salicylate, the metabolite of phenanthene degradation, to produce catechol. This complex prefers salicylate over other substituted salicylates; the other two salicylate 1-hydroxylases have different substrate preferences. RHOs utilize non-heme Fe(II) to catalyze the addition of hydroxyl groups to the aromatic ring, an initial step in the oxidative degradation of aromatic compounds. RHOs are composed of either two or three protein components, and are comprised of an electron transport chain (ETC) and an oxygenase. The ETC transfers reducing equivalents from the electron donor to the oxygenase component, which in turn transfers electrons to the oxygen molecules. The oxygenase components are oligomers, either (alpha)n or (alpha)n(beta)n. The alpha subunits are the catalytic components and have an N-terminal domain, which binds a Rieske-like 2Fe-2S cluster, and a C-terminal domain which binds the non-heme Fe(II). The Fe(II) is co-ordinated by conserved His and Asp residues. Other oxygenases belonging to this subgroup include the alpha subunits of anthranilate 1,2-dioxygenase from Burkholderia cepacia DBO1, a polycyclic aromatic hydrocarbon dioxygenase from Cycloclasticus sp. strain A5 (PhnA dioxygenase), salicylate-5-hydroxylase from Ralstonia sp. U2, ortho-halobenzoate 1,2-dioxygenase from Pseudomonas aeruginosa strain JB2, and the terephthalate 1,2-dioxygenase system from Delftia tsuruhatensis strain T7. This subfamily belongs to the SRPBCC (START/RHO_alpha_C/PITP/Bet_v1/CoxG/CalC) domain superfamily of proteins that bind hydrophobic ligands. SRPBCC domains have a deep hydrophobic ligand-binding pocket.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 197 IRANWKLLVENSNDGYHAAMTHATYLDYLANTHAKGNEVALKGVGRelgggHAVVEYTAPWGrpianwipvwGEEGKVEM 276
Cdd:cd08880     8 IPGNWKLYAENVKDPYHASLLHLFFVTFGLWRADQKSSIIDDEHGR-----HSVMTSTKSGD----------DEAAEKDS 72

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 277 DRIHARLEQ---------EHGKAKADRIcfKNRNLLIFPNLVINDIM-AVTFRTFYPLAPNYMNVSgWA-LAPTNETEWA 345
Cdd:cd08880    73 EEIRSFRDDftlldpsllDGRAEFDDDI--TLVIQSIFPSLVVQQIQnTLAVRHIIPKGPDSFELV-WTyFGYEDDDEEM 149

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1308985318 346 RKYRLNNfLEFLGPGGFATPDDVEALESCQAGYANSLESGA--EwndiskgMG------MDAMYdDEIQMRSFWKEWnRR 417
Cdd:cd08880   150 TRLRLRQ-ANLVGPAGFVSMEDGEAIEFVQRGVEGDGGDRSviE-------MGggdvesSDHMV-TEAAIRGFWKYY-RK 219

                  .
gi 1308985318 418 V 418
Cdd:cd08880   220 V 220

Cao (chlorophyll a oxygenase) is a rieske non-heme iron-sulfur protein located within the plastid-envelope inner and thylakoid membranes, that catalyzes the conversion of chlorophyllide a to chlorophyllide b. CAO is found not only in plants but also in chlorophytes and prochlorophytes. This domain represents the N-terminal rieske domain of the oxygenase alpha subunit. ROs comprise a large class of aromatic ring-hydroxylating dioxygenases that enable microorganisms to tolerate and utilize aromatic compounds for growth. The oxygenase alpha subunit contains an N-terminal Rieske domain with an [2Fe-2S] cluster and a C-terminal catalytic domain with a mononuclear Fe(II) binding site. The Rieske [2Fe-2S] cluster accepts electrons from a reductase or ferredoxin component and transfers them to the mononuclear iron for catalysis. Cao is closely related to several other plant RO's including Tic 55, a 55 kDa protein associated with protein transport through the inner chloroplast membrane; Ptc 52, a novel 52 kDa protein isolated from chloroplasts; and LLS1/Pao (Lethal-leaf spot 1/pheophorbide a oxygenase).

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1308985318  73 RDSTGKVNAFFNTCPHRGAEVcREAKGNSKHFTCMYHGWIFSADGELKNLP 123
Cdd:cd04337    46 RDEDGTPGCIRDECAHRACPL-SLGKVIEGRIQCPYHGWEYDGDGECTKMP 95

The alignment model represents the N-terminal rieske iron-sulfur domain of KshA, the oxygenase component of 3-ketosteroid 9-alpha-hydroxylase (KSH). The terminal oxygenase component of KSH is a key enzyme in the microbial steroid degradation pathway, catalyzing the 9 alpha-hydroxylation of 4-androstene-3,17-dione (AD) and 1,4-androstadiene-3,17-dione (ADD). KSH is a two-component class IA monooxygenase, with terminal oxygenase (KshA) and oxygenase reductase (KshB) components. KSH activity has been found in many actino- and proteo- bacterial genera including Rhodococcus, Nocardia, Arthrobacter, Mycobacterium, and Burkholderia.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1308985318  67 RNLIFNRDSTGKVNAFFNTCPHRGAEVCR-EAKGNSkhFTCMYHGWIFSADGELKNLPGSER 127
Cdd:cd03531    24 TKLVVFADSDGALNVLDAYCRHMGGDLSQgTVKGDE--IACPFHDWRWGGDGRCKAIPYARR 83

Tic55 is a 55kDa LLS1-related non-heme iron oxygenase associated with protein transport through the plant inner chloroplast membrane. This domain represents the N-terminal Rieske domain of the Tic55 oxygenase alpha subunit. Tic55 is closely related to the oxygenase alpha subunits of a small subfamily of enzymes found in plants as well as oxygenic cyanobacterial photosynthesizers including LLS1 (lethal leaf spot 1, also known as PaO), Ptc52, and ACD1 (accelerated cell death 1). ROs comprise a large class of aromatic ring-hydroxylating dioxygenases that enable microorganisms to tolerate and utilize aromatic compounds for growth. The oxygenase alpha subunit contains an N-terminal Rieske domain with an [2Fe-2S] cluster and a C-terminal catalytic domain with a mononuclear Fe(II) binding site. The Rieske [2Fe-2S] cluster accepts electrons from a reductase or ferredoxin component and transfers them to the mononuclear iron for catalysis.

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gi 1308985318  64 VAKRNLIFNRDSTGKVNAFFNTCPHRGAEVcREAKGNSKHFTCMYHGWIFSADGELKNLP 123
Cdd:cd04338    37 VYDEPFVLFRDQNGQLRCLEDRCPHRLAKL-SEGQLIDGKLECLYHGWQFGGEGKCVKIP 95

chlorophyllide a oxygenase

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gi 1308985318  69 LIFnRDSTGKVNAFFNTCPHRGaevCREAKG--NSKHFTCMYHGWIFSADGELKNLPGSE 126
Cdd:PLN02281  246 VIF-RGEDGKPGCVRNTCAHRA---CPLDLGtvNEGRIQCPYHGWEYSTDGECKKMPSTK 301

C-terminal catalytic domain of GbcA (glycine betaine catabolism A) from Pseudomonas aeruginosa PAO1 and related aromatic ring hydroxylating dioxygenases; C-terminal catalytic domain of GbcA (glycine betaine catabolism A) from Pseudomonas aeruginosa PAO1 and related Rieske-type non-heme iron aromatic ring-hydroxylating oxygenases (RHOs, also known as aromatic ring hydroxylating dioxygenases). RHOs utilize non-heme Fe(II) to catalyze the addition of hydroxyl groups to the aromatic ring, an initial step in the oxidative degradation of aromatic compounds. RHOs are composed of either two or three protein components, and are comprised of an electron transport chain (ETC) and an oxygenase. The ETC transfers reducing equivalents from the electron donor to the oxygenase component, which in turn transfers electrons to the oxygen molecules. The oxygenase components are oligomers, either (alpha)n or (alpha)n(beta)n. The alpha subunits are the catalytic components and have an N-terminal domain, which binds a Rieske-like 2Fe-2S cluster, and a C-terminal domain which binds the non-heme Fe(II). The Fe(II) is co-ordinated by conserved His and Asp residues. GbcA is involved in glycine betaine (GB) catabolism in Pseudomonas aeruginosa; it may remove a methyl group from GB via a dioxygenase mechanism, producing dimethylglycine and formaldehyde. This subfamily belongs to the SRPBCC (START/RHO_alpha_C/PITP/Bet_v1/CoxG/CalC) domain superfamily of proteins that bind hydrophobic ligands. SRPBCC domains have a deep hydrophobic ligand-binding pocket.

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gi 1308985318 192 QQDYAIRANWKLLVENSNDGYHAAMTH 218
Cdd:cd08884    13 RISYEVAANWKLVVENYRECYHCAGVH 39