M14 family of metallocarboxypeptidases and related proteins; The M14 family of metallocarboxypeptidases (MCPs), also known as funnelins, are zinc-binding carboxypeptidases (CPs) which hydrolyze single, C-terminal amino acids from polypeptide chains, and have a recognition site for the free C-terminal carboxyl group, which is a key determinant of specificity. Two major subfamilies of the M14 family, defined based on sequence and structural homology, are the A/B and N/E subfamilies. Enzymes belonging to the A/B subfamily are normally synthesized as inactive precursors containing preceding signal peptide, followed by an N-terminal pro-region linked to the enzyme; these proenzymes are called procarboxypeptidases. The A/B enzymes can be further divided based on their substrate specificity; Carboxypeptidase A-like (CPA-like) enzymes favor hydrophobic residues while carboxypeptidase B-like (CPB-like) enzymes only cleave the basic residues lysine or arginine. The A forms have slightly different specificities, with Carboxypeptidase A1 (CPA1) preferring aliphatic and small aromatic residues, and CPA2 preferring the bulky aromatic side chains. Enzymes belonging to the N/E subfamily enzymes are not produced as inactive precursors and instead rely on their substrate specificity and subcellular compartmentalization to prevent inappropriate cleavage. They contain an extra C-terminal transthyretin-like domain, thought to be involved in folding or formation of oligomers. MCPs can also be classified based on their involvement in specific physiological processes; the pancreatic MCPs participate only in alimentary digestion and include carboxypeptidase A and B (A/B subfamily), while others, namely regulatory MCPs or the N/E subfamily, are involved in more selective reactions, mainly in non-digestive tissues and fluids, acting on blood coagulation/fibrinolysis, inflammation and local anaphylaxis, pro-hormone and neuropeptide processing, cellular response and others. Another MCP subfamily, is that of succinylglutamate desuccinylase /aspartoacylase, which hydrolyzes N-acetyl-L-aspartate (NAA), and deficiency in which is the established cause of Canavan disease. Another subfamily (referred to as subfamily C) includes an exceptional type of activity in the MCP family, that of dipeptidyl-peptidase activity of gamma-glutamyl-(L)-meso-diaminopimelate peptidase I which is involved in bacterial cell wall metabolism.

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gi 1063759728   1 MFSFSACKFNVQKSKEGTGRVVMWKMGIRNSFTMEATFCGSTLGNKRGTHFSTKDLESMGYHFCDSLLDYC 71
Cdd:cd06907   182 KFSFESCKFKVQKSKEGTGRVVMWREGILNSYTLEATFCGSTLGRRKGTHFNTLDFEAMGYHFCDTLLDYC 252

Peptidase M14-like domain of ATP/GTP binding protein AGBL-2 and AGBL-3, and related proteins; Peptidase M14-like domain of ATP/GTP binding protein_like (AGBL)-2, and related proteins. The Peptidase M14 family of metallocarboxypeptidases are zinc-binding carboxypeptidases (CPs) which hydrolyze single, C-terminal amino acids from polypeptide chains, and have a recognition site for the free C-terminal carboxyl group, which is a key determinant of specificity. This subgroup includes the human AGBL-2, and -3, and the mouse cytosolic carboxypeptidase (CCPs)-2, and -3. ATP/GTP binding protein (AGTPBP-1/Nna1)-like proteins are active metallopeptidases that are thought to act on cytosolic proteins such as alpha-tubulin, to remove a C-terminal tyrosine. Mutations in AGTPBP-1/Nna1 cause Purkinje cell degeneration (pcd). AGTPBP-1/Nna1 however does not belong to this subgroup. AGTPBP-1/Nna1-like proteins from the different phyla are highly diverse, but they all contain a unique N-terminal conserved domain right before the CP domain. It has been suggested that this N-terminal domain might act as a folding domain.

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gi 1063759728   1 MFSFSACKFNVQKSKEGTGRVVMWKMGIRNSFTMEATFCGSTLGNKRGTHFSTKDLESMGYHFCDSLLDYC 71
Cdd:cd06907   182 KFSFESCKFKVQKSKEGTGRVVMWREGILNSYTLEATFCGSTLGRRKGTHFNTLDFEAMGYHFCDTLLDYC 252

Peptidase M14-like domain of ATP/GTP binding protein AGBL-2 and AGBL-3, and related proteins; Peptidase M14-like domain of ATP/GTP binding protein_like (AGBL)-2, and related proteins. The Peptidase M14 family of metallocarboxypeptidases are zinc-binding carboxypeptidases (CPs) which hydrolyze single, C-terminal amino acids from polypeptide chains, and have a recognition site for the free C-terminal carboxyl group, which is a key determinant of specificity. This subgroup includes the human AGBL-2, and -3, and the mouse cytosolic carboxypeptidase (CCPs)-2, and -3. ATP/GTP binding protein (AGTPBP-1/Nna1)-like proteins are active metallopeptidases that are thought to act on cytosolic proteins such as alpha-tubulin, to remove a C-terminal tyrosine. Mutations in AGTPBP-1/Nna1 cause Purkinje cell degeneration (pcd). AGTPBP-1/Nna1 however does not belong to this subgroup. AGTPBP-1/Nna1-like proteins from the different phyla are highly diverse, but they all contain a unique N-terminal conserved domain right before the CP domain. It has been suggested that this N-terminal domain might act as a folding domain.

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gi 1063759728   1 MFSFSACKFNVQKSKEGTGRVVMWKMGIRNSFTMEATFCGSTLGNKRGTHFSTKDLESMGYHFCDSLLDYC 71
Cdd:cd06907   182 KFSFESCKFKVQKSKEGTGRVVMWREGILNSYTLEATFCGSTLGRRKGTHFNTLDFEAMGYHFCDTLLDYC 252

Peptidase M14-like domain of ATP/GTP binding proteins and cytosolic carboxypeptidases; Peptidase M14-like domain of Nna-1 (Nervous system Nuclear protein induced by Axotomy), also known as ATP/GTP binding protein (AGTPBP-1) and cytosolic carboxypeptidase (CCP), and related proteins. The Peptidase M14 family of metallocarboxypeptidases are zinc-binding carboxypeptidases (CPs) which hydrolyze single, C-terminal amino acids from polypeptide chains, and have a recognition site for the free C-terminal carboxyl group, which is a key determinant of specificity. This eukaryotic subgroup includes the mouse Nna1/CCP-1, and -4 proteins, and the human Nna1/AGTPBP-1 protein. Nna1-like proteins are active metallopeptidases that are thought to act on cytosolic proteins such as alpha-tubulin, to remove a C-terminal tyrosine. Nna1 is widely expressed in the developing and adult nervous systems, including cerebellar Purkinje and granule neurons, miral cells of the olfactory bulb and retinal photoreceptors. Nna1 is also induced in axotomized motor neurons. Mutations in Nna1 cause Purkinje cell degeneration (pcd). The Nna1 CP domain is required to prevent the retinal photoreceptor loss and cerebellar ataxia phenotypes of pcd mice, and a functional zinc-binding domain is needed for Nna-1 to support neuron survival in these mice. Nna1-like proteins from the different phyla are highly diverse, but they all contain a unique N-terminal conserved domain right before the CP domain. It has been suggested that this N-terminal domain might act as a folding domain.

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gi 1063759728   2 FSFSACKFNVQKSKEGTGRVVMWKM-GIRNSFTMEATFCGSTLGNKRGTHFSTKDLESMGYHFCDSLL 68
Cdd:cd06906   200 FSLSSCSFVVEKSKESTARVVVWREiGVLRSYTMESTYCGCDQGKYKGLHIGTRELEEMGARFCEALL 267