pfam01641, SelR, SelR domain. Methionine sulfoxide reduction is an important process, by which cells regulate biological processes and cope with oxidative stress. MsrA, a protein involved in the reduction of methionine sulfoxides in proteins, has been known for four decades and has been extensively characterized with respect to structure and function. However, recent studies revealed that MsrA is only specific for methionine-S-sulfoxides. Because oxidized methionines occur in a mixture of R and S isomers in vivo, it was unclear how stereo-specific MsrA could be responsible for the reduction of all protein methionine sulfoxides. It appears that a second methionine sulfoxide reductase, SelR, evolved that is specific for methionine-R-sulfoxides, the activity that is different but complementary to that of MsrA. Thus, these proteins, working together, could reduce both stereoisomers of methionine sulfoxide. This domain is found both in SelR proteins and fused with the peptide methionine sulfoxide reductase enzymatic domain pfam01625. The domain has two conserved cysteine and histidines. The domain binds both selenium and zinc. The final cysteine is found to be replaced by the rare amino acid selenocysteine in some members of the family. This family has methionine-R-sulfoxide reductase activity.
pfam07609, DUF1572, Protein of unknown function (DUF1572). These proteins, from several diverse bacteria, share a short conserved sequence towards their N termini.
cd16282, metallo-hydrolase-like_MBL-fold, uncharacterized subgroup of the MBL-fold_metallo-hydrolase superfamily; MBL-fold metallo hydrolase domain. Members of the MBL-fold metallohydrolase superfamily are mainly hydrolytic enzymes which carry out a variety of biological functions. The class B metal beta-lactamases (MBLs) for which this fold was named perform only a small fraction of the activities included in this superfamily.Activities carried out by superfamily members include class B beta-lactamases, hydroxyacylglutathione hydrolases, AHL (acyl homoserine lactone) lactonases, persulfide dioxygenases, flavodiiron proteins, cleavage and polyadenylation specificity factors such as the Int9 and Int11 subunits of Integrator, Sdsa1-like and AtsA-like arylsulfatases, 5'-exonucleases human SNM1A and yeast Pso2p, ribonuclease J and ribonuclease Z, cyclic nucleotide phosphodiesterases, insecticide hydrolases, and proteins required for natural transformation competence. Classical members of the superfamily are di-, or less commonly mono-, zinc-ion-dependent hydrolases, however the diversity of biological roles is reflected in variations in the active site metallo-chemistry.
pfam12823, DUF3817, Domain of unknown function (DUF3817). This domain is of unknown function. It is sometimes found adjacent to pfam07690 and pfam03176 which are both transporter domains.
cd01994, Alpha_ANH_like_IV, This is a subfamily of Adenine nucleotide alpha hydrolases superfamily.Adeninosine nucleotide alpha hydrolases superfamily includes N type ATP PPases and ATP sulphurylases. It forms a apha/beta/apha fold which binds to Adenosine group. This subfamily of proteins is predicted to bind ATP. This domainhas a strongly conserved motif SGGKD at the N terminus.
pfam01641, SelR, SelR domain. Methionine sulfoxide reduction is an important process, by which cells regulate biological processes and cope with oxidative stress. MsrA, a protein involved in the reduction of methionine sulfoxides in proteins, has been known for four decades and has been extensively characterized with respect to structure and function. However, recent studies revealed that MsrA is only specific for methionine-S-sulfoxides. Because oxidized methionines occur in a mixture of R and S isomers in vivo, it was unclear how stereo-specific MsrA could be responsible for the reduction of all protein methionine sulfoxides. It appears that a second methionine sulfoxide reductase, SelR, evolved that is specific for methionine-R-sulfoxides, the activity that is different but complementary to that of MsrA. Thus, these proteins, working together, could reduce both stereoisomers of methionine sulfoxide. This domain is found both in SelR proteins and fused with the peptide methionine sulfoxide reductase enzymatic domain pfam01625. The domain has two conserved cysteine and histidines. The domain binds both selenium and zinc. The final cysteine is found to be replaced by the rare amino acid selenocysteine in some members of the family. This family has methionine-R-sulfoxide reductase activity.
cd07331, M48C_Oma1_like, Peptidase M48C, integral membrane endopeptidase. This subfamily contains peptidase M48C Oma1 (also called mitochondrial metalloendopeptidase OMA1) protease homologs that are mostly uncharacterized. Oma1 is part of the quality control system in the inner membrane of mitochondria, with its catalytic site facing the matrix space. It cleaves and thereby promotes the turnover of mistranslated or misfolded membrane proteins. Oma1 can cleave the misfolded multi-pass membrane protein Oxa1, thus exerting a function similar to the ATP-dependent m-AAA protease for quality control of inner membrane proteins; it cleaves a misfolded polytopic membrane protein at multiple sites. It has been proposed that in the absence of m-AAA protease, proteolysis of Oxa1 is mediated by Oma1 in an ATP-independent manner. Oma1 is part of highly conserved mitochondrial metallopeptidases, with homologs present in higher eukaryotes, eubacteria and archaebacteria, all containing the zinc binding motif (HEXXH). It forms a high molecular mass complex in the inner membrane, possibly a homo-hexamer.
cd17482, MFS_YxiO_like, Bacillus subtilis YxiO, Listeria monocytogenes BtlA, and similar transporters of the Major Facilitator Superfamily. This family is composed of Bacillus subtilis MFS-type transporter YxiO, and similar proteins including Listeria monocytogenes BtlA. The function of B. subtilis YxiO is still unknown, and L. monocytogenes BtlA is a putative secondary transporter involved in bile tolerance and general stress resistance. This family belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.
TIGR04056, OMP_RagA_SusC, TonB-linked outer membrane protein, SusC/RagA family. This model describes a distinctive clade among the TonB-linked outer membrane proteins (OMP). Members of this family are restricted to the Bacteriodetes lineage (except for Gemmatimonas aurantiaca T-27 from the novel phylum Gemmatimonadetes) and occur in high copy numbers, with over 100 members from Bacteroides thetaiotaomicron VPI-5482 alone. Published descriptions of members of this family are available for RagA from Porphyromonas gingivalis, SusC from Bacteroides thetaiotaomicron, and OmpW from Bacteroides caccae. Members form pairs with members of the SusD/RagB family (pfam07980). Transporter complexes including these outer membrane proteins are likely to import large degradation products of proteins (e.g. RagA) or carbohydrates (e.g. SusC) as nutrients, rather than siderophores. [Transport and binding proteins, Unknown substrate].
cd14847, DD-carboxypeptidase_like, Uncharacterized proteins of the MEROPS peptidase family M15, subfamily B. This family of uncharacterized proteins similar to D-Ala-D-Ala carboxypeptidase pdcA (Myxococcus-type) are zinc-binding enzymes that belong to the peptidase M15 subfamily B. The enzyme D-Ala-D-Ala carbozypeptidase catalyzes carboxypeptidation reactions involved in bacterial cell wall metabolism.
TIGR04056, OMP_RagA_SusC, TonB-linked outer membrane protein, SusC/RagA family. This model describes a distinctive clade among the TonB-linked outer membrane proteins (OMP). Members of this family are restricted to the Bacteriodetes lineage (except for Gemmatimonas aurantiaca T-27 from the novel phylum Gemmatimonadetes) and occur in high copy numbers, with over 100 members from Bacteroides thetaiotaomicron VPI-5482 alone. Published descriptions of members of this family are available for RagA from Porphyromonas gingivalis, SusC from Bacteroides thetaiotaomicron, and OmpW from Bacteroides caccae. Members form pairs with members of the SusD/RagB family (pfam07980). Transporter complexes including these outer membrane proteins are likely to import large degradation products of proteins (e.g. RagA) or carbohydrates (e.g. SusC) as nutrients, rather than siderophores. [Transport and binding proteins, Unknown substrate].
TIGR04056, OMP_RagA_SusC, TonB-linked outer membrane protein, SusC/RagA family. This model describes a distinctive clade among the TonB-linked outer membrane proteins (OMP). Members of this family are restricted to the Bacteriodetes lineage (except for Gemmatimonas aurantiaca T-27 from the novel phylum Gemmatimonadetes) and occur in high copy numbers, with over 100 members from Bacteroides thetaiotaomicron VPI-5482 alone. Published descriptions of members of this family are available for RagA from Porphyromonas gingivalis, SusC from Bacteroides thetaiotaomicron, and OmpW from Bacteroides caccae. Members form pairs with members of the SusD/RagB family (pfam07980). Transporter complexes including these outer membrane proteins are likely to import large degradation products of proteins (e.g. RagA) or carbohydrates (e.g. SusC) as nutrients, rather than siderophores. [Transport and binding proteins, Unknown substrate].
TIGR04056, OMP_RagA_SusC, TonB-linked outer membrane protein, SusC/RagA family. This model describes a distinctive clade among the TonB-linked outer membrane proteins (OMP). Members of this family are restricted to the Bacteriodetes lineage (except for Gemmatimonas aurantiaca T-27 from the novel phylum Gemmatimonadetes) and occur in high copy numbers, with over 100 members from Bacteroides thetaiotaomicron VPI-5482 alone. Published descriptions of members of this family are available for RagA from Porphyromonas gingivalis, SusC from Bacteroides thetaiotaomicron, and OmpW from Bacteroides caccae. Members form pairs with members of the SusD/RagB family (pfam07980). Transporter complexes including these outer membrane proteins are likely to import large degradation products of proteins (e.g. RagA) or carbohydrates (e.g. SusC) as nutrients, rather than siderophores. [Transport and binding proteins, Unknown substrate].
pfam13585, CHU_C, C-terminal domain of CHU protein family. The function of this C-terminal domain is not known; there are several conserved tryptophan and asparagine residues.
pfam00583, Acetyltransf_1, Acetyltransferase (GNAT) family. This family contains proteins with N-acetyltransferase functions such as Elp3-related proteins.
pfam13585, CHU_C, C-terminal domain of CHU protein family. The function of this C-terminal domain is not known; there are several conserved tryptophan and asparagine residues.
cd09604, M1_APN_like, Peptidase M1 family similar to aminopeptidase N catalytic domain. This family contains bacterial M1 peptidases with smilarity to the catalytic domain of aminopeptidase N (APN; CD13; alanyl aminopeptidase; EC 3.4.11.2), a type II integral membrane protease belonging to the M1 gluzincin family. APN preferentially cleaves neutral amino acids from the N-terminus of oligopeptides and, in higher eukaryotes, is present in a variety of human tissues and cell types (leukocyte, fibroblast, endothelial and epithelial cells). APN expression is dysregulated in inflammatory diseases such as chronic pain, rheumatoid arthritis, multiple sclerosis, systemic sclerosis, systemic lupus erythematosus, polymyositis/dermatomyosytis and pulmonary sarcoidosis, and is enhanced in tumor cells such as melanoma, renal, prostate, pancreas, colon, gastric and thyroid cancers. It is predominantly expressed on stem cells and on cells of the granulocytic and monocytic lineages at distinct stages of differentiation, thus considered a marker of differentiation. Thus, APN inhibition may lead to the development of anti-cancer and anti-inflammatory drugs. APNs are also present in many pathogenic bacteria and represent potential drug targets. Some APNs have been used commercially, such as one from Lactococcus lactis used in the food industry. APN also serves as a receptor for coronaviruses, although the virus receptor interaction site seems to be distinct from the enzymatic site and aminopeptidase activity is not necessary for viral infection. APNs have also been extensively studied as putative Cry toxin receptors. Cry1 proteins are pore-forming toxins that bind to the midgut epithelial cell membrane of susceptible insect larvae, causing extensive damage. Several different toxins, including Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ba, Cry1Ca and Cry1Fa, have been shown to bind to APNs; however, a direct role of APN in cytotoxicity has been yet to be firmly established.
TIGR04056, OMP_RagA_SusC, TonB-linked outer membrane protein, SusC/RagA family. This model describes a distinctive clade among the TonB-linked outer membrane proteins (OMP). Members of this family are restricted to the Bacteriodetes lineage (except for Gemmatimonas aurantiaca T-27 from the novel phylum Gemmatimonadetes) and occur in high copy numbers, with over 100 members from Bacteroides thetaiotaomicron VPI-5482 alone. Published descriptions of members of this family are available for RagA from Porphyromonas gingivalis, SusC from Bacteroides thetaiotaomicron, and OmpW from Bacteroides caccae. Members form pairs with members of the SusD/RagB family (pfam07980). Transporter complexes including these outer membrane proteins are likely to import large degradation products of proteins (e.g. RagA) or carbohydrates (e.g. SusC) as nutrients, rather than siderophores. [Transport and binding proteins, Unknown substrate].
cd07333, M48C_bepA_like, Peptidase M48C Ste24p bepA-like, integral membrane protein. This family contains peptidase M48C Ste24p protease bepA (formerly yfgC)-like proteins considered to be putative metallopeptidases, containing a zinc-binding motif, HEXXH, and a COOH-terminal ER retrieval signal (KKXX). They proteolytically remove the C-terminal three residues of farnesylated proteins. They are integral membrane proteins associated with the endoplasmic reticulum and golgi, binding one zinc ion per subunit. In eukaryotes, Ste24p is required for the first NH2-terminal proteolytic processing event within the a-factor precursor, which takes place after COOH-terminal CAAX modification (C is cysteine; A is usually aliphatic; X is one of several amino acids) is complete. Mutation studies have shown that the HEXXH protease motif, which is extracellular but adjacent to a transmembrane domain and therefore close to the membrane surface, is critical for Ste24p activity. Several members of this family also contain tetratricopeptide (TPR) repeat motifs, which are involved in a variety of functions including protein-protein interactions. BepA has been shown to possess protease activity and is responsible for the degradation of incorrectly folded LptD, an essential outer-membrane protein (OMP) involved in OM transport and assembly of lipopolysaccharide. Overexpression of the bepA protease causes abnormal biofilm architecture.
pfam12412, DUF3667, Protein of unknown function (DUF3667). This domain family is found in bacteria and eukaryotes, and is approximately 50 amino acids in length. There is a single completely conserved residue P that may be functionally important.
sd00045, ANK, ankyrin repeats. Ankyrin repeats are one of the most abundant repeat motifs, and generally function as scaffolds for protein-protein interactions in processes including cell cycle, transcriptional regulation, signal transduction, vesicular trafficking, and inflammatory response. Although predominantly found in eukaryotic proteins, they are also found in some bacterial and viral proteins. Less is known of their physiological roles in prokaryotes. Some bacterial ANK proteins play key roles in microbial pathogenesis by mimicking or manipulating host function(s). The pathogen Providencia alcalifaciens N-formyltransferase ankyrin repeats function in small molecule binding and allosteric control. Ankyrin-repeat proteins have been associated with a number of human diseases.
The bacterium proteins that are colored denote the protein is present at specific phage-related keywords (such as 'capsid', 'head', 'integrase', 'plate', 'tail', 'fiber', 'coat', 'transposase', 'portal', 'terminase', 'protease' or 'lysin' and 'tRNA')
