pfam13338, AbiEi_4, Transcriptional regulator, AbiEi antitoxin. AbiEi_4 is the cognate antitoxin of the type IV toxin-antitoxin 'innate immunity' bacterial abortive infection (Abi) system that protects bacteria from the spread of a phage infection. The Abi system is activated upon infection with phage to abort the cell thus preventing the spread of phage through viral replication. There are some 20 or more Abis, and they are predominantly plasmid-encoded lactococcal systems. TA, toxin-antitoxin, systems on plasmids function by killing cells that lose the plasmid upon division. AbiE phage resistance systems function as novel Type IV TAs and are widespread in bacteria and archaea. The cognate antitoxin is pfam13338.
cd00093, HTH_XRE, Helix-turn-helix XRE-family like proteins. Prokaryotic DNA binding proteins belonging to the xenobiotic response element family of transcriptional regulators.
pfam07929, PRiA4_ORF3, Plasmid pRiA4b ORF-3-like protein. Members of this family are similar to the protein product of ORF-3 found on plasmid pRiA4 in the bacterium Agrobacterium rhizogenes. This plasmid is responsible for tumorigenesis at wound sites of plants infected by this bacterium, but the ORF-3 product does not seem to be involved in the pathogenetic process. Other proteins found in this family are annotated as being putative TnpR resolvases, but no further evidence was found to back this. Moreover, another member of this family is described as a probable lexA repressor and in fact carries a LexA DNA binding domain (pfam01726), but no references were found to expand on this.
cd07404, MPP_MS158, Microscilla MS158 and related proteins, metallophosphatase domain. MS158 is an uncharacterized Microscilla protein with a metallophosphatase domain. Microscilla proteins MS152, and MS153 are also included in this family. The domain present in members of this family belongs to the metallophosphatase (MPP) superfamily. MPPs are functionally diverse, but all share a conserved domain with an active site consisting of two metal ions (usually manganese, iron, or zinc) coordinated with octahedral geometry by a cage of histidine, aspartate, and asparagine residues. The MPP superfamily includes: Mre11/SbcD-like exonucleases, Dbr1-like RNA lariat debranching enzymes, YfcE-like phosphodiesterases, purple acid phosphatases (PAPs), YbbF-like UDP-2,3-diacylglucosamine hydrolases, and acid sphingomyelinases (ASMases). The conserved domain is a double beta-sheet sandwich with a di-metal active site made up of residues located at the C-terminal side of the sheets. This domain is thought to allow for productive metal coordination.
cd02869, PseudoU_synth_RluA_like, Pseudouridine synthase, RluA family. This group is comprised of eukaryotic, bacterial and archeal proteins similar to eight site specific Escherichia coli pseudouridine synthases: RsuA, RluA, RluB, RluC, RluD, RluE, RluF and TruA. Pseudouridine synthases catalyze the isomerization of specific uridines in a n RNA molecule to pseudouridines (5-ribosyluracil, psi) requiring no cofactors. E. coli RluC for example makes psi955, 2504 and 2580 in 23S RNA. Some psi sites such as psi1917 in 23S RNA made by RluD are universally conserved. Other psi sites occur in a more restricted fashion, for example psi2819 in 21S mitochondrial ribosomal RNA made by S. cerevisiae Pus5p is only found in mitochondrial large subunit rRNAs from some other species and in gram negative bacteria. The E. coli counterpart of this psi residue is psi2580 in 23S rRNA. psi2604in 23S RNA made by RluF has only been detected in E.coli.
pfam08843, AbiEii, Nucleotidyl transferase AbiEii toxin, Type IV TA system. This family was recently identified as belonging to the nucleotidyltransferase superfamily. AbiEii is the cognate toxin of the type IV toxin-antitoxin 'innate immunity' bacterial abortive infection (Abi) system that protects bacteria from the spread of a phage infection. The Abi system is activated upon infection with phage to abort the cell thus preventing the spread of phage through viral replication. There are some 20 or more Abis, and they are predominantly plasmid-encoded lactococcal systems. TA, toxin-antitoxin, systems on plasmids function by killing cells that lose the plasmid upon division. AbiE phage resistance systems function as novel Type IV TAs and are widespread in bacteria and archaea. The cognate antitoxin is pfam13338.
cd17793, HipA, type II toxin-antitoxin sytem toxin HipA and similar proteins. This family contains type II toxin-antitoxin (TA) system HipA family toxins similar to Escherichia coli and Shewanella oneidensis HipA, which is a serine/threonine-protein kinase that phosphorylates Glu-tRNA-ligase (GltX), preventing it from being charged, leading to an increase in uncharged tRNA(Glu). This induces amino acid starvation and the stringent response via RelA/SpoT and increased (p)ppGpp levels, which inhibits replication, transcription, translation and cell wall synthesis, reducing growth and leading to persistence and multidrug resistance. HipA is the toxin component of the HipA-HipB TA module that is a major factor in persistence and bioflim formation; its toxic effect is neutralized by its cognate antitoxin HipB. HipA, with HipB, acts as a a corepressor for transcription of the hipBA promoter. Structures of HipAB:DNA complexes from both Escherichia coli and Shewanella oneidensis reveal distinct complex assembly.
TIGR03070, couple_hipB, transcriptional regulator, y4mF family. Members of this family belong to a clade of helix-turn-helix DNA-binding proteins, among the larger family pfam01381 (HTH_3; Helix-turn-helix). Members are similar in sequence to the HipB protein of E. coli. Genes for members of the seed alignment for this protein family were found to be closely linked to genes encoding proteins related to HipA. The HibBA operon appears to have some features in common with toxin-antitoxin post-segregational killing systems. [Regulatory functions, DNA interactions].
cd05403, NT_KNTase_like, Nucleotidyltransferase (NT) domain of Staphylococcus aureus kanamycin nucleotidyltransferase, and similar proteins. S. aureus KNTase is a plasmid encoded enzyme which confers resistance to a wide range of aminoglycoside antibiotics which have a 4'- or 4''-hydroxyl group in the equatorial position, such as kanamycin A. This enzyme transfers a nucleoside monophosphate group from a nucleotide (ATP,GTP, or UTP) to the 4'-hydroxyl group of kanamycin A. This enzyme is a homodimer, having two NT active sites. The nucleotide and antibiotic binding sites of each active site include residues from each monomer. Included in this subgroup is Escherichia coli AadA5 which confers resistance to the antibiotic spectinomycin and is a putative aminoglycoside-3'-adenylyltransferase. It is part of the aadA5 cassette of a class 1 integron. This subgroup also includes Haemophilus influenzae HI0073 which forms a 2:2 heterotetramer with an unrelated protein HI0074. Structurally HI0074 is related to the substrate-binding domain of S. aureus KNTase. The genes encoding HI0073 and HI0074 form an operon. Little is known about the substrate specificity or function of two-component NTs. The characterized members of this subgroup may not be representive of the function of this subgroup. This subgroup belongs to the Pol beta-like NT superfamily. In the majority of enzymes in this superfamily, two carboxylates, Dx[D/E], together with a third more distal carboxylate, co-ordinate two divalent metal cations involved in a two-metal ion mechanism of nucleotide addition. These carboxylate residues are conserved in this subgroup.
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')
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')
