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Basic Amino Acid Antiporter Family
The Basic Amino Acid Antiporter (ArcD) family (TC# 2.A.118) is a constituent of the IT superfamily. This family consists of proteins from Gram-negative and Gram-positive bacteria (e.g., ''Streptococcus'', ''Escherichia'', ''Salmonella'', ''Fusobacterium'' and ''Borrelia'' species). The proteins are of about 480 amino acyl residues (aas) in length and have 10-12 putative transmembrane segments (TMSs). Functionally characterized homologues are in the DcuCTC #2.A.61 and ArsBTC #2.A.4 families. Some members of the family probably catalyze arginine/ornithine or citrulline/ornithine antiport. See also * Ion transporter superfamily * Amino acid transporter An amino acid transporter is a membrane transport protein that transports amino acids. They are mainly of the solute carrier family. Families There are several families that function in amino acid transport, some of these include: TC# 2.A.3- ...s * DcuC * ArsB and ArsAB * Transporter Classification Database References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ion Transporter
In biology, a transporter is a transmembrane protein that moves ions (or other small molecules) across a biological membrane to accomplish many different biological functions including, cellular communication, maintaining homeostasis, energy production, etc. There are different types of transporters including, pumps, uniporters, antiporters, and symporters. Active transporters or ion pumps are transporters that convert energy from various sources—including adenosine triphosphate (ATP), sunlight, and other redox reactions—to potential energy by pumping an ion up its concentration gradient. This potential energy could then be used by secondary transporters, including ion carriers and ion channels, to drive vital cellular processes, such as ATP synthesis. This page is focused mainly on ion transporters acting as pumps, but transporters can also function to move molecules through facilitated diffusion. Facilitated diffusion does not require ATP and allows molecules, that are unable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DcuC Family
The C4-dicarboxylate uptake C family or DcuC familyTC# 2.A.61 is a family of transmembrane ion transporters found in bacteria. A representative list of proteins belonging to the DcuC family can be found in the Transporter Classification Database. An anaerobic C4-dicarboxylate transporter (DcuC) of ''E. coli''TC# 2.A.61.1.1 has 14 putative transmembrane regions, is induced only under anaerobic conditions, and is not repressed by glucose. DcuC may therefore function as a succinate efflux system during anaerobic glucose fermentation. However, when overexpressed, it can replace either DcuA or DcuB in catalysing fumarate-succinate exchange and fumarate uptake. DcuC shows the same transport modes as DcuA and DcuB (exchange, uptake, and presumably efflux of C4-dicarboxylates). The reactions probably catalyzed by the ''E. coli'' DcuC protein are: # C4-dicarboxylate (out) + nH+ (out) → C4-dicarboxylate (in) + nH+ (in) # C4-dicarboxylate1 (out) + C4-dicarboxylate2 (in) ⇌ C4-dicarboxyla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmembrane Transporters
A transmembrane protein (TP) is a type of integral membrane protein that spans the entirety of the cell membrane. Many transmembrane proteins function as gateways to permit the transport of specific substances across the membrane. They frequently undergo significant conformational changes to move a substance through the membrane. They are usually highly hydrophobic and aggregate and precipitate in water. They require detergents or nonpolar solvents for extraction, although some of them (beta-barrels) can be also extracted using denaturing agents. The peptide sequence that spans the membrane, or the transmembrane segment, is largely hydrophobic and can be visualized using the hydropathy plot. Depending on the number of transmembrane segments, transmembrane proteins can be classified as single-span (or bitopic) or multi-span (polytopic). Some other integral membrane proteins are called monotopic, meaning that they are also permanently attached to the membrane, but do not pass t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmembrane Proteins
A transmembrane protein (TP) is a type of integral membrane protein that spans the entirety of the cell membrane. Many transmembrane proteins function as gateways to permit the transport of specific substances across the membrane. They frequently undergo significant conformational changes to move a substance through the membrane. They are usually highly hydrophobic and aggregate and precipitate in water. They require detergents or nonpolar solvents for extraction, although some of them (beta-barrels) can be also extracted using denaturing agents. The peptide sequence that spans the membrane, or the transmembrane segment, is largely hydrophobic and can be visualized using the hydropathy plot. Depending on the number of transmembrane segments, transmembrane proteins can be classified as single-span (or bitopic) or multi-span (polytopic). Some other integral membrane proteins are called monotopic, meaning that they are also permanently attached to the membrane, but do not pass t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Proteins
Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins are a permanent part of a cell membrane and can either penetrate the membrane (transmembrane) or associate with one or the other side of a membrane ( integral monotopic). Peripheral membrane proteins are transiently associated with the cell membrane. Membrane proteins are common, and medically important—about a third of all human proteins are membrane proteins, and these are targets for more than half of all drugs. Nonetheless, compared to other classes of proteins, determining membrane protein structures remains a challenge in large part due to the difficulty in establishing experimental conditions that can preserve the correct conformation of the protein in isolation from its native environment. Function Membrane proteins perform a variety of functions vital to the surv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Families
A protein family is a group of evolutionarily related proteins. In many cases, a protein family has a corresponding gene family, in which each gene encodes a corresponding protein with a 1:1 relationship. The term "protein family" should not be confused with family as it is used in taxonomy. Proteins in a family descend from a common ancestor and typically have similar three-dimensional structures, functions, and significant sequence similarity. The most important of these is sequence similarity (usually amino-acid sequence), since it is the strictest indicator of homology and therefore the clearest indicator of common ancestry. A fairly well developed framework exists for evaluating the significance of similarity between a group of sequences using sequence alignment methods. Proteins that do not share a common ancestor are very unlikely to show statistically significant sequence similarity, making sequence alignment a powerful tool for identifying the members of protein familie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ArsB And ArsAB Transporters
Arsenite resistance (Ars) efflux pumps of bacteria may consist of two proteins, ArsBTC# 2.A.45.1.1 the integral membrane constituent with twelve transmembrane spanners) and ArsATC# 3.A.4.1.1 the ATP-hydrolyzing, transport energizing subunit, as for the chromosomally-encoded ''E. coli'' system), or of one protein (just the ArsB integral membrane protein of the plasmid-encoded ''Staphylococcus'' system). ArsA proteins have two ATP binding domains and probably arose by a tandem gene duplication event. ArsB proteins all possess twelve transmembrane spanners and may also have arisen by a tandem gene duplication event. Structurally, the Ars pumps resemble ABC-type efflux pumps, but there is no significant sequence similarity between the Ars and ABC pumps. When only ArsB is present, the system operates by a pmf-dependent mechanism, and consequently belongs in TC subclass 2.A (i.eTC# 2.A.45. When ArsA is also present, ATP hydrolysis drives efflux, and consequently the system belongs in T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid Transporter
An amino acid transporter is a membrane transport protein that transports amino acids. They are mainly of the solute carrier family. Families There are several families that function in amino acid transport, some of these include: TC# 2.A.3- Amino Acid-Polyamine-Organocation (APC) Superfamily TC# 2.A.18- Amino Acid/Auxin Permease (AAAP) Family TC# 2.A.23- Dicarboxylate/Amino Acid:Cation (Na+ or H+) Symporter (DAACS) Family TC# 2.A.26- Branched Chain Amino Acid:Cation Symporter (LIVCS) Family TC# 2.A.42- Hydroxy/Aromatic Amino Acid Permease (HAAAP) Family TC# 2.A.78- Branched Chain Amino Acid Exporter (LIV-E) Family TC# 2.A.95- 6TMS Neutral Amino Acid Transporter (NAAT) Family TC# 2.A.118- Basic Amino Acid Antiporter (ArcD) Family TC# 2.A.120- Putative Amino Acid Permease (PAAP) Family Solute carrier family examples * (1) high affinity glutamate and neutral amino acid transporter * (3) heavy subunits of heteromeric amino acid transporters * (6) Bacterial Leucine Transp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-negative Bacteria
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall sandwiched between an inner cytoplasmic cell membrane and a bacterial outer membrane. Gram-negative bacteria are found in virtually all environments on Earth that support life. The gram-negative bacteria include the model organism ''Escherichia coli'', as well as many pathogenic bacteria, such as ''Pseudomonas aeruginosa'', '' Chlamydia trachomatis'', and ''Yersinia pestis''. They are a significant medical challenge as their outer membrane protects them from many antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and lysozyme, an antimicrobial enzyme produced by animals that forms part of the innate immune system. Additionally, the outer leaflet of this membrane comprises a complex lipopol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ion Transporter Superfamily
The ion transporter (IT) superfamily is a protein superfamily, superfamily of secondary carriers that transport proteins, transport charged substrates. Families As of early 2016, the currently recognized and functionally defined families that make up the IT superfamily include: 2.A.8- Gluconate-Proton symporter, The Gluconate:H+ Symporter (GntP) Family 2.A.11- Citrate symporter, The Citrate-Mg2+:H+ (CitM) Citrate-Ca2+:H+ (CitH) Symporter (CitMHS) Family 2.A.13- C4-dicarboxylate uptake, The C4-Dicarboxylate Uptake (Dcu) Family 2.A.14- Lactate permease, The Lactate Permease (LctP) Family 2.A.34- NhaB family, The NhaB Na+:H+ Antiporter (NhaB) Family 2.A.35- NhaC family, The NhaC Na+:H+ Antiporter (NhaC) Family 2.A.45- ArsB and ArsAB transporters, The Arsenite-Antimonite (ArsB) Efflux Family 2.A.47- Divalent anion-Sodium symporter, The Divalent Anion:Na+ Symporter (DASS) Family 2.A.61- DcuC family, The C4-dicarboxylate Uptake C (DcuC) Family 2.A.62- NhaD family, The NhaD Na+:H+ Anti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borrelia
''Borrelia'' is a genus of bacteria of the spirochete phylum. Several species cause Lyme disease, also called Lyme borreliosis, a zoonotic, vector-borne disease transmitted by ticks. Other species of ''Borrelia'' cause relapsing fever, and are transmitted by ticks or lice, depending on the species of bacteria. A few ''Borrelia'' species as ''Candidatus'' Borrelia mahuryensis harbor intermediate genetic features between Lyme disease and relapsing fever ''Borrelia''. The genus is named after French biologist Amédée Borrel (1867–1936), who first documented the distinction between a species of ''Borrelia'', ''B. anserina'', and the other known type of spirochete at the time, ''Treponema pallidum''. This bacterium must be viewed using dark-field microscopy, which make the cells appear white against a dark background. ''Borrelia'' species are grown in Barbour-Stoenner-Kelly medium. Of 52 known species of ''Borrelia'', 20 are members of the Lyme disease group (with an additional 3 p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
