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Natural Resistance-Associated Macrophage Proteins
Natural resistance-associated macrophage proteins (Nramps), also known as metal ion (Mn2+-iron) transportersTC# 2.A.55, are a family of metal transport proteins found throughout all domains of life. Taking on an eleven-helix LeuT fold, the Nramp family is a member of the large APC Superfamily of secondary carriers. They transport a variety of transition metals such as manganese, cadmium, and manganese using an alternating access mechanism characteristic of secondary transporters. The name "natural resistance-associated" macrophage proteins arises from the role in resistance of intracellular bacterial pathogens played by some animal homologs. Several human pathologies may result from defects in Nramp-dependent Fe2+ or Mn2+ transport, including iron overload, neurodegenerative diseases and innate susceptibility to infectious diseases. Human homologs Humans and rodents possess two distinct Nramp proteins. The broad specificity NRAMP2 (DMT1) transports a range of divalent metal cat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transport Protein
A transport protein (variously referred to as a transmembrane pump, transporter, escort protein, acid transport protein, cation transport protein, or anion transport protein) is a protein that serves the function of moving other materials within an organism. Transport proteins are vital to the growth and life of all living things. There are several different kinds of transport proteins. Carrier proteins are proteins involved in the movement of ions, small molecules, or macromolecules, such as another protein, across a biological membrane. Carrier proteins are integral membrane proteins; that is, they exist within and span the membrane across which they transport substances. The proteins may assist in the movement of substances by facilitated diffusion (i.e., passive transport) or active transport. These mechanisms of movement are known as carrier-mediated transport. Each carrier protein is designed to recognize only one substance or one group of very similar substances. Resea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmembrane Transporters
A transmembrane protein 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-pass membrane proteins, or as multipass membrane proteins. Some other integral membrane proteins are called monotopic, meaning that they are also permanently attached to the membrane, but do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmembrane Proteins
A transmembrane protein 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-pass membrane proteins, or as multipass membrane proteins. Some other integral membrane proteins are called monotopic, meaning that they are also permanently attached to the membrane, bu ... [...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 protein, transmembrane) or associate with one or the other side of a membrane (Integral monotopic protein, 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 (Native state, native) Protein structure, conformation of the protein in isolation from its native ... [...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. Sequence similarity (usually amino-acid sequence) is one of the most common indicators of homology, or common evolutionary ancestry. Some frameworks for evaluating the significance of similarity between sequences use sequence alignment methods. Proteins that do not share a common ancestor are unlikely to show statistically significant sequence similarity, making sequence alignment a powerful tool for identifying the members of protein families. Families are sometimes grouped together into larger clades called superfamilies based on stru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transporter Classification Database
The Transporter Classification Database (or TCDB) is an International Union of Biochemistry and Molecular Biology (IUBMB)-approved classification system for membrane transport proteins, including ion channels. Classification The upper level of classification and a few examples of proteins with known 3D structure: 1. Channels and pores 1.A α-type channels * 1.A.1 Voltage-gated ion channel superfamily * 1.A.2 Inward-rectifier K+ channel family * 1.A.3 Ryanodine-inositol-1,4,5-trisphosphate receptor Ca2+ channel family * 1.A.4 Transient receptor potential Ca2+ channel family * 1.A.5 Polycystin cation channel family * 1.A.6 Epithelial Na+ channel family * 1.A.7 ATP-gated P2X receptor cation channel family * 1.A.8 Major intrinsic protein superfamily * 1.A.9 Neurotransmitter receptor, Cys loop, ligand-gated ion channel family * 1.A.10 Glutamate-gated ion channel family of neurotransmitter receptors * 1.A.11 Ammonium channel transporter family * 1.A.12 Intracellular chlorid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferroportin
Ferroportin-1, also known as solute carrier family 40 member 1 (SLC40A1) or iron-regulated transporter 1 (IREG1), is a protein that in humans is encoded by the ''SLC40A1'' gene. Ferroportin is a transmembrane protein that transports iron from the inside of a cell to the outside of the cell. Ferroportin is the only known iron exporter. After dietary iron is absorbed into the cells of the small intestine, ferroportin allows that iron to be transported out of those cells and into the bloodstream. Fpn also mediates the efflux of iron recycled from macrophages resident in the spleen and liver. Ferroportin is regulated by hepcidin, a hormone produced by the liver; hepcidin binds to Fpn and limits its iron-efflux activity, thereby reducing iron delivery to the blood plasma. Therefore, the interaction between Fpn and hepcidin controls systemic iron homeostasis. Structure Members of the ferroportin family consist of 400-800 amino acid residues, with a highly conserved histidine at resi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solute Carrier Family
The solute carrier (SLC) group of membrane transport proteins include over 400 members organized into 66 families. Most members of the SLC group are located in the cell membrane. The SLC gene nomenclature system was originally proposed by the HUGO Gene Nomenclature Committee (HGNC) and is the basis for the official HGNC names of the genes that encode these transporters. A more general transmembrane transporter classification can be found in TCDB, TCDB database. Solutes that are transported by the various SLC group members are extremely diverse and include both charged and uncharged organic molecules as well as inorganic ions and the gas Ammonia transporter, ammonia. As is typical of integral membrane proteins, SLCs contain a number of hydrophobic transmembrane Alpha helix, alpha helices connected to each other by hydrophilic intra- and extra-cellular loops. Depending on the SLC, these transporters are functional as either monomers or obligate homo- or hetero-oligomers. Many SLC fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deinococcus Radiodurans
''Deinococcus radiodurans'' is a bacterium, an extremophile and one of the most radiation-resistant organisms known. It can survive cold, dehydration, vacuum, and acid, and therefore is known as a polyextremophile. ''The Guinness Book Of World Records'' listed it in January 1998 as the world's most radiation-resistant bacterium or lifeform. Several bacteria of comparable radioresistance are known, including some species of the genus '' Chroococcidiopsis'' (phylum cyanobacteria) and some species of '' Rubrobacter'' (phylum Actinomycetota); among the archaea, the species '' Thermococcus gammatolerans'' shows comparable radioresistance. Name and classification The name ''Deinococcus radiodurans'' derives from the Ancient Greek δεινός () and κόκκος () meaning "terrible grain/berry" and the Latin and , meaning "radiation-surviving". The species was formerly called ''Micrococcus radiodurans''. As a consequence of its hardiness, it has been nicknamed “Conan the Bacteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SLC11A2
Natural resistance-associated macrophage protein 2 (NRAMP 2), also known as divalent metal transporter 1 (DMT1) and divalent cation transporter 1 (DCT1), is a protein that in humans is encoded by the ''SLC11A2'' (solute carrier family 11, member 2) gene. DMT1 represents a large family of orthologous metal ion transporter proteins that are highly conserved from bacteria to humans. As its name suggests, DMT1 binds a variety of divalent metals including cadmium (Cd2+), copper (Cu2+), and zinc (Zn2+,); however, it is best known for its role in transporting ferrous iron (Fe2+). DMT1 expression is regulated by body iron stores to maintain iron homeostasis. DMT1 is also important in the absorption and transport of manganese (Mn2+). In the digestive tract, it is located on the apical membrane of enterocytes, where it carries out H+-coupled transport of divalent metal cations from the intestinal lumen into the cell. Function Iron is not only essential for the human body, it is required f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
