>gnl|CDD|143496 cd06822, PLPDE_III_YBL036c_euk, Pyridoxal 5-phosphate (PLP)-binding TIM barrel domain of Type III PLP-Dependent Enzymes, Eukaryotic YBL036c-like proteins
This subfamily contains mostly uncharacterized eukaryotic proteins with similarity to the yeast hypothetical protein YBL036c, which is homologous to a Pseudomonas aeruginosa gene that is co-transcribed with a known proline biosynthetic gene. YBL036c is a single domain monomeric protein with a typical TIM barrel fold. It binds the PLP cofactor and has been shown to exhibit amino acid racemase activity. The YBL036c structure is similar to the N-terminal domain of the fold type III PLP-dependent enzymes, bacterial alanine racemase and eukaryotic ornithine decarboxylase, which are two-domain dimeric proteins. The lack of a second domain in YBL036c may explain limited D- to L-alanine racemase or non-specific racemase activity. Some members of this subfamily are also referred to as PROSC (Proline synthetase co-transcribed bacterial homolog). Length = 227
>gnl|CDD|143497 cd06824, PLPDE_III_Yggs_like, Pyridoxal 5-phosphate (PLP)-binding TIM barrel domain of Type III PLP-Dependent Enzymes, Yggs-like proteins
This subfamily contains mainly uncharacterized proteobacterial proteins with similarity to the hypothetical Escherichia coli protein YggS, a homolog of yeast YBL036c, which is homologous to a Pseudomonas aeruginosa gene that is co-transcribed with a known proline biosynthetic gene. Like yeast YBL036c, Yggs is a single domain monomeric protein with a typical TIM-barrel fold. Its structure, which shows a covalently-bound PLP cofactor, is similar to the N-terminal domain of the fold type III PLP-dependent enzymes, bacterial alanine racemase and eukaryotic ornithine decarboxylase, which are two-domain dimeric proteins. YggS has not been characterized extensively and its biological function is still unkonwn. Length = 224
>gnl|CDD|143483 cd00635, PLPDE_III_YBL036c_like, Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzymes, YBL036c-like proteins
Score = 72.5 bits (179), Expect = 3e-17
Identities = 27/62 (43%), Positives = 32/62 (51%), Gaps = 5/62 (8%)
Query: 3 AAIKGTLEKVEQACARRPQELQWSRPRLVAVSKTKPKELIIEAYNGGQRHFGENYVQELL 62
++ + + R P E LVAVSKT P E I EA GQR FGEN VQE L
Sbjct: 6 EEVRERIAAAAERAGRDPDE-----VTLVAVSKTVPAEAIREAIEAGQRDFGENRVQEAL 60
Query: 63 EK 64
+K
Sbjct: 61 DK 62
This family contains mostly uncharacterized proteins, widely distributed among eukaryotes, bacteria and archaea, that bear similarity to the yeast hypothetical protein YBL036c, which is homologous to a Pseudomonas aeruginosa gene that is co-transcribed with a known proline biosynthetic gene. YBL036c is a single domain monomeric protein with a typical TIM barrel fold. It binds the PLP cofactor and has been shown to exhibit amino acid racemase activity. The YBL036c structure is similar to the N-terminal domain of the fold type III PLP-dependent enzymes, bacterial alanine racemase and eukaryotic ornithine decarboxylase, which are two-domain dimeric proteins. The lack of a second domain in YBL036c may explain limited D- to L-alanine racemase or non-specific racemase activity. Length = 222
>gnl|CDD|223402 COG0325, COG0325, Predicted enzyme with a TIM-barrel fold [General function prediction only]
Score = 64.5 bits (157), Expect = 4e-14
Identities = 30/64 (46%), Positives = 37/64 (57%), Gaps = 5/64 (7%)
Query: 3 AAIKGTLEKVEQACARRPQELQWSRPRLVAVSKTKPKELIIEAYNGGQRHFGENYVQELL 62
IK +E R P ++ +L+AVSKTKP I AY+ GQR FGENYVQEL+
Sbjct: 9 EDIKTKIEAANTHVNRNPSKV-----KLLAVSKTKPASAIQIAYDAGQRAFGENYVQELV 63
Query: 63 EKGH 66
EK
Sbjct: 64 EKIK 67
Members of this protein family include YggS from Escherichia coli and YBL036C, an uncharacterized pyridoxal protein of Saccharomyces cerevisiae [Unknown function, Enzymes of unknown specificity]. Length = 229
>cd06822 PLPDE_III_YBL036c_euk Pyridoxal 5-phosphate (PLP)-binding TIM barrel domain of Type III PLP-Dependent Enzymes, Eukaryotic YBL036c-like proteins
This subfamily contains mostly uncharacterized eukaryotic proteins with similarity to the yeast hypothetical protein YBL036c, which is homologous to a Pseudomonas aeruginosa gene that is co-transcribed with a known proline biosynthetic gene. YBL036c is a single domain monomeric protein with a typical TIM barrel fold. It binds the PLP cofactor and has been shown to exhibit amino acid racemase activity. The YBL036c structure is similar to the N-terminal domain of the fold type III PLP-dependent enzymes, bacterial alanine racemase and eukaryotic ornithine decarboxylase, which are two-domain dimeric proteins. The lack of a second domain in YBL036c may explain limited D- to L-alanine racemase or non-specific racemase activity. Some members of this subfamily are also referred to as PROSC (Proline synthetase co-transcribed bacterial homolog)
This subfamily contains mainly uncharacterized proteobacterial proteins with similarity to the hypothetical Escherichia coli protein YggS, a homolog of yeast YBL036c, which is homologous to a Pseudomonas aeruginosa gene that is co-transcribed with a known proline biosynthetic gene. Like yeast YBL036c, Yggs is a single domain monomeric protein with a typical TIM-barrel fold. Its structure, which shows a covalently-bound PLP cofactor, is similar to the N-terminal domain of the fold type III PLP-dependent enzymes, bacterial alanine racemase and eukaryotic ornithine decarboxylase, which are two-domain dimeric proteins. YggS has not been characterized extensively and its biological function is still unkonwn.
>cd00635 PLPDE_III_YBL036c_like Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzymes, YBL036c-like proteins
This family contains mostly uncharacterized proteins, widely distributed among eukaryotes, bacteria and archaea, that bear similarity to the yeast hypothetical protein YBL036c, which is homologous to a Pseudomonas aeruginosa gene that is co-transcribed with a known proline biosynthetic gene. YBL036c is a single domain monomeric protein with a typical TIM barrel fold. It binds the PLP cofactor and has been shown to exhibit amino acid racemase activity. The YBL036c structure is similar to the N-terminal domain of the fold type III PLP-dependent enzymes, bacterial alanine racemase and eukaryotic ornithine decarboxylase, which are two-domain dimeric proteins. The lack of a second domain in YBL036c may explain limited D- to L-alanine racemase or non-specific racemase activity.
>cd06815 PLPDE_III_AR_like_1 Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzyme Alanine Racemase-like 1
This subfamily is composed of uncharacterized bacterial proteins with similarity to bacterial alanine racemases (AR), which are fold type III PLP-dependent enzymes containing an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain. AR exists as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. It catalyzes the interconversion between L- and D-alanine, which is an essential component of the peptidoglycan layer of bacterial cell walls. Members of this subfamily may act as PLP-dependent enzymes.
>cd00430 PLPDE_III_AR Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzyme Alanine Racemase
This family includes predominantly bacterial alanine racemases (AR), some serine racemases (SerRac), and putative bifunctional enzymes containing N-terminal UDP-N-acetylmuramoyl-tripeptide:D-alanyl-D-alanine ligase (murF) and C-terminal AR domains. These proteins are fold type III PLP-dependent enzymes that play essential roles in peptidoglycan biosynthesis. AR catalyzes the interconversion between L- and D-alanine, which is an essential component of the peptidoglycan layer of bacterial cell walls. SerRac converts L-serine into its D-enantiomer (D-serine) for peptidoglycan synthesis. murF catalyzes the addition of D-Ala-D-Ala to UDPMurNAc-tripeptide, the final step in the synthesis of the cytoplasmic precursor of bacterial cell wall peptidoglycan. Members of this family contain an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain. They exist as homodimers with activ
>PF01168 Ala_racemase_N: Alanine racemase, N-terminal domain; InterPro: IPR001608 Alanine racemase plays a role in providing the D-alanine required for cell wall biosynthesis by isomerising L-alanine to D-alanine
Proteins containing this domain are found in both prokaryotes and eukaryotes [,]. The molecular structure of alanine racemase from Bacillus stearothermophilus was determined by X-ray crystallography to a resolution of 1.9 A []. The alanine racemase monomer is composed of two domains, an eight-stranded alpha/beta barrel at the N terminus, and a C-terminal domain essentially composed of beta-strands. The pyridoxal 5'-phosphate (PLP) cofactor lies in and above the mouth of the alpha/beta barrel and is covalently linked via an aldimine linkage to a lysine residue, which is at the C terminus of the first beta-strand of the alpha/beta barrel. This domain is also found in the PROSC (proline synthetase co-transcribed bacterial homolog) family of proteins, which are not known to have alanine racemase activity.; PDB: 3KW3_A 1B54_A 1CT5_A 2ODO_B 2RJG_A 3B8V_D 2RJH_D 3B8T_D 3B8W_B 3B8U_A ....
This enzyme interconverts L-alanine and D-alanine. Its primary function is to generate D-alanine for cell wall formation. With D-alanine-D-alanine ligase, it makes up the D-alanine branch of the peptidoglycan biosynthetic route. It is a monomer with one pyridoxal phosphate per subunit. In E. coli, the ortholog is duplicated so that a second isozyme, DadX, is present. DadX, a paralog of the biosynthetic Alr, is induced by D- or L-alanine and is involved in catabolism.
This family includes eukaryotic D-serine dehydratases (DSD), cryptic DSDs from bacteria, D-threonine aldolases (D-TA), low specificity D-TAs, and similar uncharacterized proteins. DSD catalyzes the dehydration of D-serine to aminoacrylate, which is rapidly hydrolyzed to pyruvate and ammonia. D-TA reversibly catalyzes the aldol cleavage of D-threonine into glycine and acetaldehyde, and the synthesis of D-threonine from glycine and acetaldehyde. Members of this family are fold type III PLP-dependent enzymes, similar to bacterial alanine racemase (AR), which contains an N-terminal PLP-binding TIM barrel domain and a C-terminal beta-sandwich domain. AR exists as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. Based on similarity to AR, it is poss
>cd06811 PLPDE_III_yhfX_like Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzyme yhfX
This subfamily is composed of the uncharacterized protein yhfX from Escherichia coli K-12 and similar bacterial proteins. These proteins are homologous to bacterial alanine racemases (AR), which are fold type III PLP-dependent enzymes containing an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain. AR exists as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. It catalyzes the interconversion between L- and D-alanine, which is an essential component of the peptidoglycan layer of bacterial cell walls. Members of this subfamily may act as PLP-dependent enzymes.
>cd06821 PLPDE_III_D-TA Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzyme D-Threonine Aldolase
D-threonine aldolase (D-TA, EC 4.3.1.18) reversibly catalyzes the aldol cleavage of D-threonine into glycine and acetaldehyde, and the synthesis of D-threonine from glycine and acetaldehyde. Its activity is present in several genera of bacteria but not in fungi. It requires PLP and a divalent cation such as Co2+, Ni2+, Mn2+, or Mg2+ as cofactors for catalytic activity and thermal stability. Members of this subfamily show similarity to bacterial alanine racemase (AR), a fold type III PLP-dependent enzyme which contains an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain. AR exists as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. Based on its similarity to AR, it is possible that low specificity D-TAs also form dimers in solution. Experimental data show that
>cd06808 PLPDE_III Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzymes
The fold type III PLP-dependent enzyme family is predominantly composed of two-domain proteins with similarity to bacterial alanine racemases (AR) including eukaryotic ornithine decarboxylases (ODC), prokaryotic diaminopimelate decarboxylases (DapDC), biosynthetic arginine decarboxylases (ADC), carboxynorspermidine decarboxylases (CANSDC), and similar proteins. AR-like proteins contain an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain. They exist as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. These proteins play important roles in the biosynthesis of amino acids and polyamine. The family also includes the single-domain YBL036c-like proteins, which contain a single PLP-binding TIM-barrel domain without any N- or C-terminal extensions. Due to the lack of a second domain, these p
>cd06825 PLPDE_III_VanT Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzymes, VanT and similar proteins
This subfamily is composed of Enterococcus gallinarum VanT and similar proteins. VanT is a membrane-bound serine racemase (EC 5.1.1.18) that is essential for vancomycin resistance in Enterococcus gallinarum. It converts L-serine into its D-enantiomer (D-serine) for peptidoglycan synthesis. The C-terminal region of this protein contains a PLP-binding TIM-barrel domain followed by beta-sandwich domain, which is homologous to the fold type III PLP-dependent enzyme, bacterial alanine racemase (AR). AR exists as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. On the basis of this similarity, it has been suggested that dimer formation of VanT is required for its catalytic activity, and that it catalyzes the racemization of serine in a mechanistically similar manner to that of alanine by
>cd06820 PLPDE_III_LS_D-TA_like Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzymes, Low Specificity D-Threonine Aldolase-like
This subfamily is composed of uncharacterized bacterial proteins with similarity to low specificity D-threonine aldolase (D-TA), which is a fold type III PLP-dependent enzyme that catalyzes the interconversion between D-threonine/D-allo-threonine and glycine plus acetaldehyde. Both PLP and divalent cations (eg. Mn2+) are required for catalytic activity. Low specificity D-TAs show similarity to bacterial alanine racemase (AR), which contains an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain. AR exists as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. Based on its similarity to AR, it is possible that low specificity D-TAs also form dimers in solution. Experimental data show that the monomeric form of low specificity D-TAs exh
>cd06826 PLPDE_III_AR2 Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzyme, Alanine Racemase 2
This subfamily is composed of bacterial alanine racemases (EC 5.1.1.1) with similarity to Yersinia pestis and Vibrio cholerae alanine racemase (AR) 2. ARs catalyze the interconversion between L- and D-alanine, an essential component of the peptidoglycan layer of bacterial cell walls. These proteins are similar to other bacterial ARs and are fold type III PLP-dependent enzymes containing contains an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain. They exist as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. Homodimer formation and the presence of the PLP cofactor are required for catalytic activity.
>TIGR03619 F420_Rv2161c probable F420-dependent oxidoreductase, Rv2161c family
Coenzyme F420 has a limited phylogenetic distribution, including methanogenic archaea, Mycobacterium tuberculosis and related species, Colwellia psychrerythraea 34H, Rhodopseudomonas palustris HaA2, and others. Partial phylogenetic profiling identifies protein subfamilies, within the larger family called luciferase-like monooxygenanases (pfam00296), that appear only in F420-positive genomes and are likely to be F420-dependent. This model describes a domain found in a distinctive subset of bacterial luciferase homologs, found only in F420-biosynthesizing members of the Actinobacteria.
>COG3457 Predicted amino acid racemase [Amino acid transport and metabolism]
Low specificity D-threonine aldolase (Low specificity D-TA, EC 4.3.1.18), encoded by dtaAS gene from Arthrobacter sp. strain DK-38, is the prototype of this subfamily. Low specificity D-TAs are fold type III PLP-dependent enzymes that catalyze the interconversion between D-threonine/D-allo-threonine and glycine plus acetaldehyde. Both PLP and divalent cations (eg. Mn2+) are required for catalytic activity. Members of this subfamily show similarity to bacterial alanine racemase (AR), which contains an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain. AR exists as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. Based on its similarity to AR, it is possible that low specificity D-TAs also form dimers in solution. Experimental data show that t
>3r79_A Uncharacterized protein; PSI-biology, structural genomics, NEW YORK structural genomi research consortium, TIM barrel; HET: PLP; 1.90A {Agrobacterium tumefaciens}
>3co8_A Alanine racemase; protein structure initiative II, PSI-II, PLP, TIM barrel, structural genomics, NEW YORK SGX center for structural genomics; HET: PLP; 1.70A {Oenococcus oeni}
