cd01544, PBP1_GalR, ligand-binding domain of DNA transcription repressor GalR which is one of two regulatory proteins involved in galactose transport and metabolism. Ligand-binding domain of DNA transcription repressor GalR which is one of two regulatory proteins involved in galactose transport and metabolism. Transcription of the galactose regulon genes is regulated by Gal iso-repressor (GalS) and Gal repressor (GalR) in different ways, but both repressors recognize the same DNA binding site in the absence of D-galactose. GalR is a dimeric protein like GalS and is exclusively involved in the regulation of galactose permease, the low-affinity galactose transporter. GalS is involved in regulating expression of the high-affinity galactose transporter encoded by the mgl operon. GalS and GalR are members of the LacI-GalR family of transcription regulators and both contain the type 1 periplasmic binding protein-like fold. Hence, they are structurally homologous to the periplasmic sugar binding of ABC-type transport systems.
TIGR00792, Melibiose_carrier_protein, sugar (Glycoside-Pentoside-Hexuronide) transporter. The Glycoside-Pentoside-Hexuronide (GPH):Cation Symporter Family (TC 2.A.2) GPH:cation symporters catalyze uptake of sugars in symport with a monovalent cation (H+ or Na+). Members of this family includes transporters for melibiose, lactose, raffinose, glucuronides, pentosides and isoprimeverose. Mutants of two groups of these symporters (the melibiose permeases of enteric bacteria, and the lactose permease of Streptococcus thermophilus) have been isolated in which altered cation specificity is observed or in which sugar transport is uncoupled from cation symport (i.e., uniport is catalyzed). The various members of the family can use Na+, H+ or Li, Na+ or Li+, H+ or Li+, or only H+ as the symported cation. All of these proteins possess twelve putative transmembrane a-helical spanners. [Transport and binding proteins, Carbohydrates, organic alcohols, and acids].
cd07208, Pat_hypo_Ecoli_yjju_like, Hypothetical patatin similar to yjju protein of Escherichia coli. Patatin-like phospholipase similar to yjju protein of Escherichia coli. This family predominantly consists of bacterial patatin glycoproteins, and some representatives from eukaryotes and archaea. The patatin protein accounts for up to 40% of the total soluble protein in potato tubers. Patatin is a storage protein, but it also has the enzymatic activity of a lipid acyl hydrolase, catalyzing the cleavage of fatty acids from membrane lipids. Members of this family have also been found in vertebrates.
cd00995, PBP2_NikA_DppA_OppA_like, The substrate-binding domain of an ABC-type nickel/oligopeptide-like import system contains the type 2 periplasmic binding fold. This family represents the periplasmic substrate-binding domain of nickel/dipeptide/oligopeptide transport systems, which function in the import of nickel and peptides, and other closely related proteins. The oligopeptide-binding protein OppA is a periplasmic component of an ATP-binding cassette (ABC) transport system OppABCDEF consisting of five subunits: two homologous integral membrane proteins OppB and OppF that form the translocation pore; two homologous nucleotide-binding domains OppD and OppF that drive the transport process through binding and hydrolysis of ATP; and the substrate-binding protein or receptor OppA that determines the substrate specificity of the transport system. The dipeptide (DppA) and oligopeptide (OppA) binding proteins differ in several ways. The DppA binds dipeptides and some tripeptides and is involved in chemotaxis toward dipeptides, whereas the OppA binds peptides of a wide range of lengths (2-35 amino acid residues) and plays a role in recycling of cell wall peptides, which precludes any involvement in chemotaxis. Similar to the ABC-type dipeptide and oligopeptide import systems, nickel transporter is comprised of five subunits NikABCDE: the two pore-forming integral inner membrane proteins NikB and NikC; the two inner membrane-associated proteins with ATPase activity NikD and NikE; and the periplasmic nickel binding NikA, which is the initial nickel receptor that controls the chemotactic response away from nickel. Most of other periplasmic binding proteins are comprised of only two globular subdomains corresponding to domains I and III of the dipeptide/oligopeptide binding proteins. The structural topology of these domains is most similar to that of the type 2 periplasmic binding proteins (PBP2), which are responsible for the uptake of a variety of substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. The PBP2 bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis. Besides transport proteins, the PBP2 superfamily includes the ligand binding domains of ionotropic glutamate receptors, LysR-type transcriptional regulators, and unorthodox sensor proteins involved in signal transduction.
COG1168, MalY, Bifunctional PLP-dependent enzyme with beta-cystathionase and maltose regulon repressor activities [Amino acid transport and metabolism].
cd18547, ABC_6TM_Tm288_like, Six-transmembrane helical domain Tm288 of a heterodimeric ABC transporter Tm287/288 from Thermotoga maritima and similar proteins. This group represents the six-transmembrane helical domain (Tm288) of a heterodimeric ABC transporter Tm287/288 from Thermotoga maritima and similar proteins. This TMD possesses the ATP-binding cassette (ABC) exporter fold, which is characterized by 6 TM helices per subunit (domain), or a total of 12 TM helices for the complete transporter. The ABC exporters are found in both prokaryotes and eukaryotes, where they mediate the cellular secretion of toxic compounds, a various type of lipids and polypeptides. ABC transporters typically consist of two transmembrane domains (TMDs) and two nucleotide-binding domains (NBDs). The sequences and structures of the TMDs are quite varied between the different type of transporters, suggesting significant structural diversity of the translocated substrates, while NBDs are conserved among all ABC transporters. The two NBDs together bind and hydrolyze ATP, thereby providing the driving force for transport, while the TMDs participate in substrate recognition and translocation across the lipid membrane by alternating between inward- and outward-facing conformations. Moreover, some ABC genes are organized as half-transporters, which must form either homodimers or heterodimers to form a functional transporter. The ABC exporters play a role in multidrug resistance to antibiotics and anticancer agents, and mutations in these proteins have been shown to cause severe human diseases such as cystic fibrosis.
pfam02604, PhdYeFM_antitox, Antitoxin Phd_YefM, type II toxin-antitoxin system. Members of this family act as antitoxins in type II toxin-antitoxin systems. When bound to their toxin partners, they can bind DNA via the N-terminus and repress the expression of operons containing genes encoding the toxin and the antitoxin. This domain complexes with Txe toxins containing pfam06769, Fic/DOC toxins containing pfam02661 and YafO toxins containing pfam13957.
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')
