Catalytic domain of phospholipase D superfamily proteins; Catalytic domain of phospholipase D (PLD) superfamily proteins. The PLD superfamily is composed of a large and diverse group of proteins including plant, mammalian and bacterial PLDs, bacterial cardiolipin (CL) synthases, bacterial phosphatidylserine synthases (PSS), eukaryotic phosphatidylglycerophosphate (PGP) synthase, eukaryotic tyrosyl-DNA phosphodiesterase 1 (Tdp1), and some bacterial endonucleases (Nuc and BfiI), among others. PLD enzymes hydrolyze phospholipid phosphodiester bonds to yield phosphatidic acid and a free polar head group. They can also catalyze the transphosphatidylation of phospholipids to acceptor alcohols. The majority of members in this superfamily contain a short conserved sequence motif (H-x-K-x(4)-D, where x represents any amino acid residue), called the HKD signature motif. There are varying expanded forms of this motif in different family members. Some members contain variant HKD motifs. Most PLD enzymes are monomeric proteins with two HKD motif-containing domains. Two HKD motifs from two domains form a single active site. Some PLD enzymes have only one copy of the HKD motif per subunit but form a functionally active dimer, which has a single active site at the dimer interface containing the two HKD motifs from both subunits. Different PLD enzymes may have evolved through domain fusion of a common catalytic core with separate substrate recognition domains. Despite their various catalytic functions and a very broad range of substrate specificities, the diverse group of PLD enzymes can bind to a phosphodiester moiety. Most of them are active as bi-lobed monomers or dimers, and may possess similar core structures for catalytic activity. They are generally thought to utilize a common two-step ping-pong catalytic mechanism, involving an enzyme-substrate intermediate, to cleave phosphodiester bonds. The two histidine residues from the two HKD motifs play key roles in the catalysis. Upon substrate binding, a histidine from one HKD motif could function as the nucleophile, attacking the phosphodiester bond to create a covalent phosphohistidine intermediate, while the other histidine residue from the second HKD motif could serve as a general acid, stabilizing the leaving group.

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gi 705704750   1 FTWLCSQVHTSLATHFRGQIVAEFDKEFQYLYAES 35
Cdd:cd09183  240 FTWLSSQVHSNLVTHFRGNIVEEFDREFRCLYADS 274

N-terminal phospholipase D-like domain of the uncharacterized protein, Family with sequence similarity 83C; N-terminal phospholipase D (PLD)-like domain of the uncharacterized protein, Family with sequence similarity 83C (FAM83C). Since the N-terminal PLD-like domain of FAM83 proteins shows only trace similarity to the PLD catalytic domain and lacks the functionally important histidine residue, FAM83 proteins may share a similar three-dimensional fold with PLD enzymes, but are most unlikely to carry PLD activity. The N-terminus of FAM83C shows high homology to other FAM83 family members, indicating that FAM83C might have arisen early in vertebrate evolution by duplication of a gene in the FAM83 family.

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gi 705704750   1 FTWLCSQVHTSLATHFRGQIVAEFDKEFQYLYAES 35
Cdd:cd09183  240 FTWLSSQVHSNLVTHFRGNIVEEFDREFRCLYADS 274

N-terminal phospholipase D-like domain of the uncharacterized protein, Family with sequence similarity 83C; N-terminal phospholipase D (PLD)-like domain of the uncharacterized protein, Family with sequence similarity 83C (FAM83C). Since the N-terminal PLD-like domain of FAM83 proteins shows only trace similarity to the PLD catalytic domain and lacks the functionally important histidine residue, FAM83 proteins may share a similar three-dimensional fold with PLD enzymes, but are most unlikely to carry PLD activity. The N-terminus of FAM83C shows high homology to other FAM83 family members, indicating that FAM83C might have arisen early in vertebrate evolution by duplication of a gene in the FAM83 family.

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gi 705704750   1 FTWLCSQVHTSLATHFRGQIVAEFDKEFQYLYAES 35
Cdd:cd09183  240 FTWLSSQVHSNLVTHFRGNIVEEFDREFRCLYADS 274

N-terminal phospholipase D-like domain of proteins from the Family with sequence similarity 83; N-terminal phospholipase D (PLD)-like domain of vetebrate proteins from the Family with sequence similarity 83 (FAM83), which is comprised of 8 members, designated FAM83A through FAM83H. Since the N-terminal PLD-like domain of FAM83 proteins shows only trace similarity to the PLD catalytic domain and lacks the functionally important histidine residue, the FAM83 proteins may share a similar three-dimensional fold with PLD enzymes, but are unlikely to carry PLD activity. Members of the FAM83 are mostly uncharacterized proteins. FAM83A, also known as tumor antigen BJ-TSA-9, is a novel tumor-specific gene highly expressed in human lung adenocarcinoma. FAM83D, also known as spindle protein CHICA, is a cell-cycle-regulated spindle component which localizes to the mitotic spindle and is both upregulated and phosphorylated during mitosis. The gene encoding protein FAM83H is the first gene involved in the etiology of amelogenesis imperfecta (AI), that encodes a non-secreted protein due to the absence of a signal peptide. Defects in gene FAM83H cause autosomal dominant hypocalcified amelogenesis imperfecta (ADHCAI). FAM83B, FAM83C, FAM83F, and FAM83G are uncharacterized proteins present across vertebrates while FAM83E is an uncharacterized protein found only in mammals.

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gi 705704750   1 FTWLCSQVHTSLATHFRGQIVAEFDKEFQYLYAES 35
Cdd:cd09119  235 FTWSDAKLHRSMLSVLTGQVVESFDEEFRILYAQS 269

N-terminal phospholipase D-like domain of the uncharacterized protein, Family with sequence similarity 83B; N-terminal phospholipase D (PLD)-like domain of the uncharacterized protein, Family with sequence similarity 83B (FAM83B). Since the N-terminal PLD-like domain of FAM83 proteins shows only trace similarity to the PLD catalytic domain and lacks the functionally important histidine residue, FAM83 proteins may share a similar three-dimensional fold with PLD enzymes, but are most unlikely to carry PLD activity. The N-terminus of FAM83B shows high homology to other FAM83 family members, indicating that FAM83B might have arisen early in vertebrate evolution by duplication of a gene in the FAM83 family.

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gi 705704750   1 FTWLCSQVHTSLATHFRGQIVAEFDKEFQYLYAESravtsfCVP 44
Cdd:cd09182  229 YMWSFEKIHLSMVQVITGQLVESYDEEFRTLYARS------AVP 266

N-terminal phospholipase D-like domain of the protein, Family with sequence similarity 83D; N-terminal phospholipase D (PLD)-like domain of the protein Family with sequence similarity 83D (FAM83D), also known as spindle protein CHICA. CHICA is a cell-cycle-regulated spindle component, which localizes to the mitotic spindle and is both upregulated and phosphorylated during mitosis. CHICA is required to localize the chromokinesin Kid to the mitotic spindle and serves as a novel interaction partner of Kid, which is required for the generation of polar ejection forces and chromosome congression. Since the N-terminal PLD-like domain of FAM83D shows only trace similarity to the PLD catalytic domain and lacks the functionally important histidine residue, FAM83D may share a similar three-dimensional fold with PLD enzymes, but is unlikely to carry PLD activity.

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gi 705704750   1 FTWLCSQVHTSLATHFRGQIVAEFDKEFQYLYAES 35
Cdd:cd09184  237 FTWTDGKLNSSNLLILSGQVVEKFDLEFRILYAQS 271