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Barstar
Barstar is a small protein synthesized by the bacterium ''Bacillus amyloliquefaciens''. Its function is to inhibit the ribonuclease activity of its binding partner barnase Barnase (a portmanteau of "BActerial" "RiboNucleASE") is a bacterial protein that consists of 110 amino acids and has ribonuclease activity. It is synthesized and secreted by the bacterium '' Bacillus amyloliquefaciens'', but is lethal to the cel ..., with which it forms an extraordinarily tightly bound complex within the cell until barnase is secreted. Expression of barstar is necessary to counter the lethal effect of expressed active barnase. The structure of the barnase-barstar complex is known. References Bacterial proteins {{protein-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barnase
Barnase (a portmanteau of "BActerial" "RiboNucleASE") is a bacterial protein that consists of 110 amino acids and has ribonuclease activity. It is synthesized and secreted by the bacterium ''Bacillus amyloliquefaciens'', but is lethal to the cell when expressed without its inhibitor barstar. The inhibitor binds to and occludes the ribonuclease active site, preventing barnase from damaging the cell's RNA after it has been synthesized but before it has been secreted. The barnase/barstar complex is noted for its extraordinarily tight protein-protein binding, with an on-rate of 108s−1M−1. Protein folding studies Barnase has no disulfide bonds, nor does it require divalent cations or non-peptide components to fold. This simplicity, in combination with its reversible folding transition, means that barnase has been extensively studied in order to understand how proteins fold. The folding of barnase has been extensively studied in the laboratory of Alan Fersht, who used it as the te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Amyloliquefaciens
''Bacillus amyloliquefaciens'' is a species of bacterium in the genus ''Bacillus'' that is the source of the BamHI restriction enzyme. It also synthesizes a natural antibiotic protein barnase, a widely studied ribonuclease that forms a famously tight complex with its intracellular inhibitor barstar, and plantazolicin, an antibiotic with selective activity against ''Bacillus anthracis''. It is used in agriculture, aquaculture, and hydroponics to fight root pathogens such as ''Ralstonia solanacearum,'' ''Pythium'', ''Rhizoctonia solani'', ''Alternaria tenuissima'' and ''Fusarium'' as well improve root tolerance to salt stress. They are considered a growth-promoting rhizobacteria and have the ability to quickly colonize roots. Discovery and name ''Bacillus amyloliquefaciens'' was discovered in soil 1943 by a Japanese scientist named Fukumoto, who gave the bacterium its name because it produced (''faciens'') a liquifying (''lique'') amylase (''amylo''). Uses Alpha amylase from ''B. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribonuclease
Ribonuclease (commonly abbreviated RNase) is a type of nuclease that catalyzes the degradation of RNA into smaller components. Ribonucleases can be divided into endoribonucleases and exoribonucleases, and comprise several sub-classes within the EC 2.7 (for the phosphorolytic enzymes) and 3.1 (for the hydrolytic enzymes) classes of enzymes. Function All organisms studied contain many RNases of two different classes, showing that RNA degradation is a very ancient and important process. As well as clearing of cellular RNA that is no longer required, RNases play key roles in the maturation of all RNA molecules, both messenger RNAs that carry genetic material for making proteins and non-coding RNAs that function in varied cellular processes. In addition, active RNA degradation systems are the first defense against RNA viruses and provide the underlying machinery for more advanced cellular immune strategies such as RNAi. Some cells also secrete copious quantities of non-specific RN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
