pfam10756, bPH_6, Bacterial PH domain. This domain has a bacterial type PH domain structure. This domain was previously known as DUF2581. This family is conserved in the Actinomycetales. Although several members are annotated as RbiX homologs, RbiX being a putative regulator of riboflavin biosynthesis, the function could not be confirmed.
cd08296, CAD_like, Cinnamyl alcohol dehydrogenases (CAD). Cinnamyl alcohol dehydrogenases (CAD), members of the medium chain dehydrogenase/reductase family, reduce cinnamaldehydes to cinnamyl alcohols in the last step of monolignal metabolism in plant cells walls. CAD binds 2 zinc ions and is NADPH- dependent. CAD family members are also found in non-plant species, e.g. in yeast where they have an aldehyde reductase activity. The medium chain dehydrogenases/reductase (MDR)/zinc-dependent alcohol dehydrogenase-like family, which contains the zinc-dependent alcohol dehydrogenase (ADH-Zn) and related proteins, is a diverse group of proteins related to the first identified member, class I mammalian ADH. MDRs display a broad range of activities and are distinguished from the smaller short chain dehydrogenases (~ 250 amino acids vs. the ~ 350 amino acids of the MDR). The MDR proteins have 2 domains: a C-terminal NAD(P) binding-Rossmann fold domain of a beta-alpha form and an N-terminal catalytic domain with distant homology to GroES. The MDR group contains a host of activities, including the founding alcohol dehydrogenase (ADHs), quinone reductase, sorbitol dehydrogenase, formaldehyde dehydrogenase, butanediol DH, ketose reductase, cinnamyl reductase, and numerous others. The zinc-dependent alcohol dehydrogenases (ADHs) catalyze the NAD(P)(H)-dependent interconversion of alcohols to aldehydes or ketones. Active site zinc has a catalytic role, while structural zinc aids in stability. ADH-like proteins typically form dimers (typically higher plants, mammals) or tetramers (yeast, bacteria), and generally have 2 tightly bound zinc atoms per subunit. The active site zinc is coordinated by a histidine, two cysteines, and a water molecule. The second zinc seems to play a structural role, affects subunit interactions, and is typically coordinated by 4 cysteines.
pfam13354, Beta-lactamase2, Beta-lactamase enzyme family. This family is closely related to Beta-lactamase, pfam00144, the serine beta-lactamase-like superfamily, which contains the distantly related pfam00905 and PF00768 D-alanyl-D-alanine carboxypeptidase.
cd14014, STKc_PknB_like, Catalytic domain of bacterial Serine/Threonine kinases, PknB and similar proteins. STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily includes many bacterial eukaryotic-type STKs including Staphylococcus aureus PknB (also called PrkC or Stk1), Bacillus subtilis PrkC, and Mycobacterium tuberculosis Pkn proteins (PknB, PknD, PknE, PknF, PknL, and PknH), among others. S. aureus PknB is the only eukaryotic-type STK present in this species, although many microorganisms encode for several such proteins. It is important for the survival and pathogenesis of S. aureus as it is involved in the regulation of purine and pyrimidine biosynthesis, cell wall metabolism, autolysis, virulence, and antibiotic resistance. M. tuberculosis PknB is essential for growth and it acts on diverse substrates including proteins involved in peptidoglycan synthesis, cell division, transcription, stress responses, and metabolic regulation. B. subtilis PrkC is located at the inner membrane of endospores and functions to trigger spore germination. Bacterial STKs in this subfamily show varied domain architectures. The well-characterized members such as S. aureus and M. tuberculosis PknB, and B. subtilis PrkC, contain an N-terminal cytosolic kinase domain, a transmembrane (TM) segment, and mutliple C-terminal extracellular PASTA domains. The PknB subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.
cd01949, GGDEF, Diguanylate-cyclase (DGC) or GGDEF domain. Diguanylate-cyclase (DGC) or GGDEF domain: Originally named after a conserved residue pattern, and initially described as a domain of unknown function 1 (DUF1). This domain is widely present in bacteria, linked to a wide range of non-homologous domains in a variety of cell signaling proteins. The domain shows homology to the adenylyl cyclase catalytic domain. This correlates with the functional information available on two GGDEF-containing proteins, namely diguanylate cyclase and phosphodiesterase A of Acetobacter xylinum, both of which regulate the turnover of cyclic diguanosine monophosphate. Together with the EAL domain, GGDEF might be involved in regulating cell surface adhesion in bacteria.
pfam02720, DUF222, Domain of unknown function (DUF222). This family is often found associated to the N-terminus of the HNH endonuclease domain pfam01844. The function of this domain is uncertain. This family has been called the 13E12 repeat family.
cd14014, STKc_PknB_like, Catalytic domain of bacterial Serine/Threonine kinases, PknB and similar proteins. STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily includes many bacterial eukaryotic-type STKs including Staphylococcus aureus PknB (also called PrkC or Stk1), Bacillus subtilis PrkC, and Mycobacterium tuberculosis Pkn proteins (PknB, PknD, PknE, PknF, PknL, and PknH), among others. S. aureus PknB is the only eukaryotic-type STK present in this species, although many microorganisms encode for several such proteins. It is important for the survival and pathogenesis of S. aureus as it is involved in the regulation of purine and pyrimidine biosynthesis, cell wall metabolism, autolysis, virulence, and antibiotic resistance. M. tuberculosis PknB is essential for growth and it acts on diverse substrates including proteins involved in peptidoglycan synthesis, cell division, transcription, stress responses, and metabolic regulation. B. subtilis PrkC is located at the inner membrane of endospores and functions to trigger spore germination. Bacterial STKs in this subfamily show varied domain architectures. The well-characterized members such as S. aureus and M. tuberculosis PknB, and B. subtilis PrkC, contain an N-terminal cytosolic kinase domain, a transmembrane (TM) segment, and mutliple C-terminal extracellular PASTA domains. The PknB subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.
pfam13376, OmdA, Bacteriocin-protection, YdeI or OmpD-Associated. This is a family of archaeal and bacterial proteins predicted to be periplasmic. YdeI is important for resistance to polymyxin B in broth and for bacterial survival in mice upon oral, but not intraperitoneal inoculation, suggesting a role for YdeI in the gastrointestinal tract of mice. Production of the ydeI gene is regulated by the Rcs (regulator of capsule synthesis) phospho-relay system pathway independently of RcsA, and additionally transcription of the protein is regulated by the stationary-phase sigma factor, RpoS (sigma-S). YdeI confers protection against cationic AMPs (Antimicrobial peptides) or bacteriocins in conjunction with the general porin Omp, thus justifying its name of OmdA, for OmpD-Associated protein.
cd02762, MopB_1, The MopB_1 CD includes a group of related uncharacterized bacterial molybdopterin-binding oxidoreductase-like domains with a putative N-terminal iron-sulfur [4Fe-4S] cluster binding site and molybdopterin cofactor binding site. These members belong to the molybdopterin_binding (MopB) superfamily of proteins.
pfam08237, PE-PPE, PE-PPE domain. This domain is found C terminal to the PE (pfam00934) and PPE (pfam00823) domains. The secondary structure of this domain is predicted to be a mixture of alpha helices and beta strands.
TIGR03883, DUF2342_F420, uncharacterized protein, coenzyme F420 biosynthesis associated. A phylogenetic tree of the DUF2342 family (TIGR03624) consists of two major branches. One of these branches, modeled here, is observed almost entirely to be found in coenzyme F420 biosynthesizing species of the Actinobacterial, Chloroflexi and Archaeal lineages. The few organisms having genes within this family and lacking F420 biosynthesis may either have an undiscovered F420 transporter, or may represent F420-to-FMN revertants. This family includes a Chloroflexus Aurantiacus protein whose crystal structure has been determined (PDB:3CMN_A). This has been annotated as a putative hydrolase, but the support for that assertion is untraceable. There is no cofactor present in the structure.
TIGR03718, R_switched_Alx, integral membrane protein, TerC family. Rfam model RF00080 describes a structured RNA element called the yybP-ykoY leader, or SraF, which may precede one or several genes in a genome. Members of this highly hydrophobic protein family often are preceded by a yybP-ykoY leader, which may serve as a riboswitch. From the larger group of TerC homologs (pfam03741), this subfamily contains TerC itself from Alcaligenes sp. plasmid IncHI2 pMER610 and from Proteus mirabilis. It also contains the alkaline-inducible E. coli protein Alx, which unlike the two TerC examples is preceded by a yybP-ykoY leader.
cd09603, M1_APN_like, Peptidase M1 family similar to aminopeptidase N catalytic domain. This family contains mostly bacterial and some archaeal 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.
cd04179, DPM_DPG-synthase_like, DPM_DPG-synthase_like is a member of the Glycosyltransferase 2 superfamily. DPM1 is the catalytic subunit of eukaryotic dolichol-phosphate mannose (DPM) synthase. DPM synthase is required for synthesis of the glycosylphosphatidylinositol (GPI) anchor, N-glycan precursor, protein O-mannose, and C-mannose. In higher eukaryotes,the enzyme has three subunits, DPM1, DPM2 and DPM3. DPM is synthesized from dolichol phosphate and GDP-Man on the cytosolic surface of the ER membrane by DPM synthase and then is flipped onto the luminal side and used as a donor substrate. In lower eukaryotes, such as Saccharomyces cerevisiae and Trypanosoma brucei, DPM synthase consists of a single component (Dpm1p and TbDpm1, respectively) that possesses one predicted transmembrane region near the C terminus for anchoring to the ER membrane. In contrast, the Dpm1 homologues of higher eukaryotes, namely fission yeast, fungi, and animals, have no transmembrane region, suggesting the existence of adapter molecules for membrane anchoring. This family also includes bacteria and archaea DPM1_like enzymes. However, the enzyme structure and mechanism of function are not well understood. The UDP-glucose:dolichyl-phosphate glucosyltransferase (DPG_synthase) is a transmembrane-bound enzyme of the endoplasmic reticulum involved in protein N-linked glycosylation. This enzyme catalyzes the transfer of glucose from UDP-glucose to dolichyl phosphate. This protein family belongs to Glycosyltransferase 2 superfamily.
TIGR02353, NON-RIBOSOMAL_PEPTIDE_SYNTHETASE, non-ribosomal peptide synthetase terminal domain of unknown function. This domain is found exclusively in non-ribosomal peptide synthetases and always as the final domain in the polypeptide. This domain is roughly 700 amino acids in size and is found in polypeptides roughly twice that size.
cd05256, UDP_AE_SDR_e, UDP-N-acetylglucosamine 4-epimerase, extended (e) SDRs. This subgroup contains UDP-N-acetylglucosamine 4-epimerase of Pseudomonas aeruginosa, WbpP, an extended SDR, that catalyzes the NAD+ dependent conversion of UDP-GlcNAc and UDPGalNA to UDP-Glc and UDP-Gal. This subgroup has the characteristic active site tetrad and NAD-binding motif of the extended SDRs. Extended SDRs are distinct from classical SDRs. In addition to the Rossmann fold (alpha/beta folding pattern with a central beta-sheet) core region typical of all SDRs, extended SDRs have a less conserved C-terminal extension of approximately 100 amino acids. Extended SDRs are a diverse collection of proteins, and include isomerases, epimerases, oxidoreductases, and lyases; they typically have a TGXXGXXG cofactor binding motif. SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold, an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Sequence identity between different SDR enzymes is typically in the 15-30% range; they catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human 15-hydroxyprostaglandin dehydrogenase numbering). In addition to the Tyr and Lys, there is often an upstream Ser and/or an Asn, contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Atypical SDRs generally lack the catalytic residues characteristic of the SDRs, and their glycine-rich NAD(P)-binding motif is often different from the forms normally seen in classical or extended SDRs. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type ketoacyl reductases have a TGXXXGX(1-2)G NAD(P)-binding motif.
TIGR01241, ATP-dependent_zinc_metalloprotease_FtsH, ATP-dependent metalloprotease FtsH. HflB(FtsH) is a pleiotropic protein required for correct cell division in bacteria. It has ATP-dependent zinc metalloprotease activity. It was formerly designated cell division protein FtsH. [Cellular processes, Cell division, Protein fate, Degradation of proteins, peptides, and glycopeptides].
cd01992, PP-ATPase, N-terminal domain of predicted ATPase of the PP-loop faimly implicated in cell cycle control [Cell division and chromosome partitioning]. 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 domain has a strongly conserved motif SGGXD at the N terminus.
TIGR00666, D-alanyl-D-alanine_carboxypeptidase_DacB, D-alanyl-D-alanine carboxypeptidase, serine-type, PBP4 family. In E. coli, this protein is known as penicillin binding protein 4 (dacB). A signal sequence is cleaved from a precursor form. The protein is described as periplasmic in E. coli (Gram-negative) and extracellular in Actinomadura R39 (Gram-positive). Unlike some other proteins with similar activity, it does not form transpeptidation. It is not essential for viability. This family is related to class A beta-lactamases. [Cell envelope, Biosynthesis and degradation of murein sacculus and peptidoglycan].
cd00093, HTH_XRE, Helix-turn-helix XRE-family like proteins. Prokaryotic DNA binding proteins belonging to the xenobiotic response element family of transcriptional regulators.
cd07263, VOC_like, uncharacterized subfamily of vicinal oxygen chelate (VOC) family. The vicinal oxygen chelate (VOC) superfamily is composed of structurally related proteins with paired beta.alpha.beta.beta.beta motifs that provide a metal coordination environment with two or three open or readily accessible coordination sites to promote direct electrophilic participation of the metal ion in catalysis. VOC domain is found in a variety of structurally related metalloproteins, including the bleomycin resistance protein, glyoxalase I, and type I ring-cleaving dioxygenases. A bound metal ion is required for protein activities for the members of this superfamily. A variety of metal ions have been found in the catalytic centers of these proteins including Fe(II), Mn(II), Zn(II), Ni(II) and Mg(II). The protein superfamily contains members with or without domain swapping. The proteins of this family share three conserved metal binding amino acids with the type I extradiol dioxygenases, which shows no domain swapping.
pfam05327, RRN3, RNA polymerase I specific transcription initiation factor RRN3. This family consists of several eukaryotic proteins which are homologous to the yeast RRN3 protein. RRN3 is one of the RRN genes specifically required for the transcription of rDNA by RNA polymerase I (Pol I) in Saccharomyces cerevisiae.
cd01189, INT_ICEBs1_C_like, C-terminal catalytic domain of integrases from bacterial phages and conjugate transposons. This family of tyrosine based site-specific integrases is has origins in bacterial phages and conjugate transposons. One member is the integrase from Bacillus subtilis conjugative transposon ICEBs1. ICEBs1 can be excised and transfered to various recipients in response to DNA damage or high concentrations of potential mating partners. The family belongs to the superfamily of DNA breaking-rejoining enzymes, which share the same fold in their catalytic domain and the overall reaction mechanism. The catalytic domain contains six conserved active site residues. Their overall reaction mechanism involves cleavage of a single strand of a DNA duplex by nucleophilic attack of a conserved tyrosine to give a 3' phosphotyrosyl protein-DNA adduct. In the second rejoining step, a terminal 5' hydroxyl attacks the covalent adduct to release the enzyme and generate duplex DNA.
TIGR01554, prophage_Lp3_protein_18, phage major capsid protein, HK97 family. This model family represents the major capsid protein component of the heads (capsids) of bacteriophage HK97, phi-105, P27, and related phage. This model represents one of several analogous families lacking detectable sequence similarity. The gene encoding this component is typically located in an operon encoding the small and large terminase subunits, the portal protein and the prohead or maturation protease. [Mobile and extrachromosomal element functions, Prophage functions].
pfam05133, Phage_prot_Gp6, Phage portal protein, SPP1 Gp6-like. This protein forms a hole, or portal, that enables DNA passage during packaging and ejection. It also forms the junction between the phage head (capsid) and the tail proteins. During SPP1 morphogenesis, Gp6 participates in the procapsid assembly reaction. This family also includes the old Pfam family Phage_min_cap (PF05126).
pfam02720, DUF222, Domain of unknown function (DUF222). This family is often found associated to the N-terminus of the HNH endonuclease domain pfam01844. The function of this domain is uncertain. This family has been called the 13E12 repeat family.
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')
