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Tyrocidine
Tyrocidine is a mixture of cyclic decapeptides produced by the bacteria ''Bacillus brevis'' found in soil. It can be composed of 4 different amino acid sequences, giving tyrocidine A–D (See figure 1). Tyrocidine is the major constituent of tyrothricin, which also contains gramicidin.Pubchem: Tyrocidine and Tyrothricin. Tyrocidine was the first commercially available antibiotic, but has been found to be toxic toward human blood and reproductive cells. The function of tyrocidine within its host ''B. brevis'' is thought to be regulation of sporulation. Tyrocidines A, B, and C are cyclic decapeptides. The biosynthesis of tyrocidine involves three enzymes. Parts of its sequence are identical to gramicidin S. History In 1939, the American microbiologist René Dubos discovered the soil microbe ''Bacillus brevis''. He observed the ability of the microbe to decompose the capsule of pneumococcus bacterium, rendering it harmless. From the soil microbe ''B. brevis'', he isolated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrocidine Syn
Tyrocidine is a mixture of cyclic decapeptides produced by the bacteria ''Bacillus brevis'' found in soil. It can be composed of 4 different amino acid sequences, giving tyrocidine A–D (See figure 1). Tyrocidine is the major constituent of tyrothricin, which also contains gramicidin.Pubchem: Tyrocidine and Tyrothricin. Tyrocidine was the first commercially available antibiotic, but has been found to be toxic toward human blood and reproductive cells. The function of tyrocidine within its host ''B. brevis'' is thought to be regulation of sporulation. Tyrocidines A, B, and C are cyclic decapeptides. The biosynthesis of tyrocidine involves three enzymes. Parts of its sequence are identical to gramicidin S. History In 1939, the American microbiologist René Dubos discovered the soil microbe ''Bacillus brevis''. He observed the ability of the microbe to decompose the capsule of pneumococcus bacterium, rendering it harmless. From the soil microbe ''B. brevis'', he isolated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrocidine Operon
Tyrocidine is a mixture of cyclic decapeptides produced by the bacteria ''Bacillus brevis'' found in soil. It can be composed of 4 different amino acid sequences, giving tyrocidine A–D (See figure 1). Tyrocidine is the major constituent of tyrothricin, which also contains gramicidin.Pubchem: Tyrocidine and Tyrothricin. Tyrocidine was the first commercially available antibiotic, but has been found to be toxic toward human blood and reproductive cells. The function of tyrocidine within its host ''B. brevis'' is thought to be regulation of sporulation. Tyrocidines A, B, and C are cyclic decapeptides. The biosynthesis of tyrocidine involves three enzymes. Parts of its sequence are identical to gramicidin S. History In 1939, the American microbiologist René Dubos discovered the soil microbe ''Bacillus brevis''. He observed the ability of the microbe to decompose the capsule of pneumococcus bacterium, rendering it harmless. From the soil microbe ''B. brevis'', he isolated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrocidine H-bonding
Tyrocidine is a mixture of cyclic decapeptides produced by the bacteria ''Bacillus brevis'' found in soil. It can be composed of 4 different amino acid sequences, giving tyrocidine A–D (See figure 1). Tyrocidine is the major constituent of tyrothricin, which also contains gramicidin.Pubchem: Tyrocidine and Tyrothricin. Tyrocidine was the first commercially available antibiotic, but has been found to be toxic toward human blood and reproductive cells. The function of tyrocidine within its host ''B. brevis'' is thought to be regulation of sporulation. Tyrocidines A, B, and C are cyclic decapeptides. The biosynthesis of tyrocidine involves three enzymes. Parts of its sequence are identical to gramicidin S. History In 1939, the American microbiologist René Dubos discovered the soil microbe ''Bacillus brevis''. He observed the ability of the microbe to decompose the capsule of pneumococcus bacterium, rendering it harmless. From the soil microbe ''B. brevis'', he isolated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrocidine Cyclization
Tyrocidine is a mixture of cyclic decapeptides produced by the bacteria ''Bacillus brevis'' found in soil. It can be composed of 4 different amino acid sequences, giving tyrocidine A–D (See figure 1). Tyrocidine is the major constituent of tyrothricin, which also contains gramicidin.Pubchem: Tyrocidine and Tyrothricin. Tyrocidine was the first commercially available antibiotic, but has been found to be toxic toward human blood and reproductive cells. The function of tyrocidine within its host ''B. brevis'' is thought to be regulation of sporulation. Tyrocidines A, B, and C are cyclic decapeptides. The biosynthesis of tyrocidine involves three enzymes. Parts of its sequence are identical to gramicidin S. History In 1939, the American microbiologist René Dubos discovered the soil microbe ''Bacillus brevis''. He observed the ability of the microbe to decompose the capsule of pneumococcus bacterium, rendering it harmless. From the soil microbe ''B. brevis'', he isolated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrocidine Domain Organization
Tyrocidine is a mixture of cyclic decapeptides produced by the bacteria ''Bacillus brevis'' found in soil. It can be composed of 4 different amino acid sequences, giving tyrocidine A–D (See figure 1). Tyrocidine is the major constituent of tyrothricin, which also contains gramicidin.Pubchem: Tyrocidine and Tyrothricin. Tyrocidine was the first commercially available antibiotic, but has been found to be toxic toward human blood and reproductive cells. The function of tyrocidine within its host ''B. brevis'' is thought to be regulation of sporulation. Tyrocidines A, B, and C are cyclic decapeptides. The biosynthesis of tyrocidine involves three enzymes. Parts of its sequence are identical to gramicidin S. History In 1939, the American microbiologist René Dubos discovered the soil microbe ''Bacillus brevis''. He observed the ability of the microbe to decompose the capsule of pneumococcus bacterium, rendering it harmless. From the soil microbe ''B. brevis'', he isolated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gramicidin
Gramicidin, also called gramicidin D, is a mix of ionophoric antibiotics, gramicidin A, B and C, which make up about 80%, 5%, and 15% of the mix, respectively. Each has 2 isoforms, so the mix has 6 different types of gramicidin molecules. They can be extracted from ''Brevibacillus brevis'' soil bacteria. Gramicidins are linear peptides with 15 amino acids. This is in contrast to unrelated gramicidin S, which is a cyclic peptide. Medical uses Gramicidins work as antibiotics against gram-positive bacteria like ''Bacillus subtilis'' and ''Staphylococcus aureus'', but not well against gram-negative ones like '' E. coli''. Gramicidins are used in medicinal lozenges for sore throat and in topical medicines to treat infected wounds. Gramicidins are often mixed with other antibiotics like tyrocidine and antiseptics. Gramicidins are also used in eye drops for bacterial eye infections. In drops, they are often mixed with other antibiotics like polymyxin B or neomycin. Multiple antibioti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrothricin
Tyrothricin is an antibiotic mixture which was isolated from ''Bacillus brevis'' by Rene Dubos in the late 1930s. It was later shown by Dubos and Rollin Hotchkiss to be a mixture of two different antibiotics: gramicidin and tyrocidine. Both gramicidin and tyrocidine are short polypeptides which disrupt the cell membranes of some, primarily Gram-positive, bacteria. Tyrothricin and its component antibiotics are too toxic to be taken internally but are sometimes used as topical antibiotics. Tyrothricin, and its component antibiotics, belongs to the pharmacologically related group of polypeptide antibiotic compounds including colistin, polymyxin B, and bacitracin Bacitracin is a polypeptide antibiotic. It is a mixture of related cyclic peptides produced by ''Bacillus licheniformis'' bacteria, that was first isolated from the variety "Tracy I" ( ATCC 10716) in 1945. These peptides disrupt Gram-positive bac .... There is no cross-resistance to these three agents. References { ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Brevis
''Brevibacillus brevis'' (formerly known as ''Bacillus brevis'') is a Gram-positive, aerobic, motile, spore-forming, rod-shaped bacterium commonly found in soil, air, water, and decaying matter. It is rarely associated with infectious diseases. The antibiotics gramicidin and tyrocidine were first isolated from it.Abedon, Stephen. "Bacteria Binomials." 26 Apr 1998. Ohio State University. 17 Jun 2006 . ''Brevibacillus brevis'' is catalase positive, amylase negative, casein negative, gelatinase positive, and indole negative; most strains are citrate users. Some strains are capable of oxidizing carbon monoxide Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simple ... aerobically. Optimal growth occurs at 35 °C to 55 °C. References Paenibacillaceae Bacteria described in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
D-amino Acid
D-Amino acids are amino acids where the stereogenic carbon alpha to the amino group has the D-configuration. For most naturally-occurring amino acids, this carbon has the L-configuration. D-Amino acids are occasionally found in nature as residues in proteins. They are formed from ribosomally-derived D-amino acid residues. Amino acids, as components of peptides, peptide hormones, structural and immune proteins, are the most important bioregulators involved in all life processes along with nucleic acids, carbohydrates and lipids. "Environmental D-amino acids are thought to be derived from organic diagenesis such as racemization and release from bacterial cell walls and even from microbial production." Discovery Their discovery was in the 1950s. "Auclair and Patton (1950) first reported their presence in the blood of insects and mollusks" Furthermore, they also have been identified in various mammalian tissues. The two major types of D-amino acids synthesized in and by mamm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine Monophosphate
Adenosine monophosphate (AMP), also known as 5'-adenylic acid, is a nucleotide. AMP consists of a phosphate group, the sugar ribose, and the nucleobase adenine; it is an ester of phosphoric acid and the nucleoside adenosine. As a substituent it takes the form of the prefix adenylyl-. AMP plays an important role in many cellular metabolic processes, being interconverted to Adenosine diphosphate, ADP and/or Adenosine triphosphate, ATP. AMP is also a component in the synthesis of RNA. AMP is present in all known forms of life. Production and degradation AMP does not have the high energy phosphoanhydride bond associated with ADP and ATP. AMP can be produced from Adenosine diphosphate, ADP: : 2 ADP → ATP + AMP Or AMP may be produced by the hydrolysis of one high energy phosphate bond of ADP: : ADP + H2O → AMP + phosphate, Pi AMP can also be formed by hydrolysis of Adenosine triphosphate, ATP into AMP and pyrophosphate: : ATP + H2O → AMP + pyrophosphate, PPi When RNA i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid Phase Peptide Synthesis
In organic chemistry, peptide synthesis is the production of peptides, compounds where multiple amino acids are linked via amide bonds, also known as peptide bonds. Peptides are chemically synthesized by the condensation reaction of the carboxyl group of one amino acid to the amino group of another. Protecting group strategies are usually necessary to prevent undesirable side reactions with the various amino acid side chains. Chemical peptide synthesis most commonly starts at the carboxyl end of the peptide (C-terminus), and proceeds toward the amino-terminus ( N-terminus). Protein biosynthesis (long peptides) in living organisms occurs in the opposite direction. The chemical synthesis of peptides can be carried out using classical solution-phase techniques, although these have been replaced in most research and development settings by solid-phase methods (see below). Solution-phase synthesis retains its usefulness in large-scale production of peptides for industrial purposes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyethylene Glycol
Polyethylene glycol (PEG; ) is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), depending on its molecular weight. The structure of PEG is commonly expressed as H−(O−CH2−CH2)n−OH. Uses Medical uses * Pharmaceutical-grade PEG is used as an excipient in many pharmaceutical products, in oral, topical, and parenteral dosage forms. * PEG is the basis of a number of laxatives (as ''MiraLax''). Whole bowel irrigation with polyethylene glycol and added electrolytes is used for bowel preparation before surgery or colonoscopy. * PEG is used in medicines for treating disimpaction and maintenance therapy for children with constipation. * When attached to various protein medications or drug carriers, polyethylene glycol of suitable length slows down their clearance from the blood. * The possibility that PEG could be used to fuse axons is being ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
