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Acyl Carrier Protein
The acyl carrier protein (ACP) is a cofactor of both fatty acid and polyketide biosynthesis machinery. It is one of the most abundant proteins in cells of ''E. coli.'' In both cases, the growing chain is bound to the ACP via a thioester derived from the distal thiol of a 4'-phosphopantetheine moiety. Structure The ACPs are small negatively charged α-helical bundle proteins with a high degree of structural and amino acid similarity. The structures of a number of acyl carrier proteins have been solved using various NMR and crystallography techniques. The ACPs are related in structure and mechanism to the peptidyl carrier proteins (PCP) from nonribosomal peptide synthases. Biosynthesis Subsequent to the expression of the inactive ''apo'' ACP, the 4'-phosphopantetheine moiety is attached to a serine residue. This coupling is mediated by acyl carrier protein synthase (ACPS), a 4'-phosphopantetheinyl transferase. 4'-Phosphopantetheine is a prosthetic group of several acyl carrier pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptomyces Coelicolor
''Streptomyces albidoflavus'' is a bacterium species from the genus of ''Streptomyces'' which has been isolated from soil from Poland. ''Streptomyces albidoflavus'' produces dibutyl phthalate and streptothricins. Small noncoding RNA Bacterial small RNAs are involved in post-transcriptional regulation. Using deep sequencing ''S. albidoflavus'' transcriptome was analysed at the end of exponential growth. 63 small RNAs were identified. Expression of 11 of them was confirmed by Northern blot. The sRNAs were shown to be only present in ''Streptomyces'' species. sRNA scr4677 (''Streptomyces coelicolor'' sRNA 4677) is located in the intergenic region between anti-sigma factor ''SCO4677'' gene and a putative regulatory protein gene ''SCO4676''. ''scr4677'' expression requires the ''SCO4677'' activity and ''scr4677'' sRNA itself seem to affect the levels of the ''SCO4676''-associated transcripts. Targets of two of ''S. albidoflavus'' noncoding RNAs have been identified. Noncoding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinorhodin
Actinorhodin is a benzoisochromanequinone dimer (chemistry), dimer polyketide antibiotic produced by ''Streptomyces coelicolor''. The gene cluster responsible for actinorhodin production contains the biosynthetic enzymes and genes responsible for export of the antibiotic. The antibiotic also has the effect of being a pH indicator A pH indicator is a halochromism, halochromic chemical compound added in small amounts to a Solution (chemistry), solution so the pH (acidity or Base (chemistry), basicity) of the solution can be determined visually or spectroscopically by chang ... due to its pH-dependent color change. It is a product of a Type II polyketide synthase biosynthetic pathway. References Hydroxyarenes Antibiotics Acetate esters Polyketides 3-Hydroxypropenals within hydroxyquinones {{antibiotic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Acid
In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated and unsaturated compounds#Organic chemistry, saturated or unsaturated. Most naturally occurring fatty acids have an Branched chain fatty acids, unbranched chain of an even number of carbon atoms, from 4 to 28. Fatty acids are a major component of the lipids (up to 70% by weight) in some species such as microalgae but in some other organisms are not found in their standalone form, but instead exist as three main classes of esters: triglycerides, phospholipids, and cholesteryl esters. In any of these forms, fatty acids are both important diet (nutrition), dietary sources of fuel for animals and important structural components for cell (biology), cells. History The concept of fatty acid (''acide gras'') was introduced in 1813 by Michel Eugène Chevreul, though he initially used some variant terms: ''graisse acide'' and ''acide huileux'' ("acid fat" and "oi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyketide
In organic chemistry, polyketides are a class of natural products derived from a Precursor (chemistry), precursor molecule consisting of a Polymer backbone, chain of alternating ketone (, or Carbonyl reduction, its reduced forms) and Methylene group, methylene () groups: . First studied in the early 20th century, discovery, biosynthesis, and application of polyketides has evolved. It is a large and diverse group of secondary metabolites caused by its complex biosynthesis which resembles that of fatty acid synthesis. Because of this diversity, polyketides can have various medicinal, agricultural, and industrial applications. Many polyketides are medicinal or exhibit acute toxicity. Biotechnology has enabled discovery of more naturally-occurring polyketides and evolution of new polyketides with novel or improved bioactivity. History Naturally produced polyketides by various plants and organisms have been used by humans since before studies on them began in the 19th and 20th century ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphopantetheine
Phosphopantetheine, also known as 4'-phosphopantetheine, is a prosthetic group of several acyl carrier proteins including the acyl carrier proteins (ACP) of fatty acid synthases, ACPs of polyketide synthases, the peptidyl carrier proteins (PCP), as well as aryl carrier proteins (ArCP) of nonribosomal peptide synthetases (NRPS). It is also present in formyltetrahydrofolate dehydrogenase. Subsequent to the expression of the ''apo'' acyl carrier protein, 4'-phosphopantetheine moiety is attached to a serine residue. The coupling involves formation of a phosphodiester linkage. This coupling is mediated by acyl carrier protein synthase (ACPS), a 4'-phosphopantetheinyl transferase. Phosphopantetheine prosthetic group covalently links to the acyl group via a high energy thioester bond. The flexibility and length of the phosphopantetheine chain (approximately 2 nm) allows the covalently tethered intermediates to access spatially distinct enzyme-active sites. This accessibility ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein NMR
Nuclear magnetic resonance spectroscopy of proteins (usually abbreviated protein NMR) is a field of structural biology in which NMR spectroscopy is used to obtain information about the structure and dynamics of proteins, and also nucleic acids, and their complexes. The field was pioneered by Richard R. Ernst and Kurt Wüthrich at the ETH, and by Ad Bax, Marius Clore, Angela Gronenborn at the National Institutes of Health, NIH, and Gerhard Wagner (physicist), Gerhard Wagner at Harvard University, among others. Structure determination by NMR spectroscopy usually consists of several phases, each using a separate set of highly specialized techniques. The sample is prepared, measurements are made, interpretive approaches are applied, and a structure is calculated and validated. NMR involves the quantum-mechanical properties of the central core ("Atomic nucleus, nucleus") of the atom. These properties depend on the local molecular environment, and their measurement provides a map of how t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonribosomal Peptide
Nonribosomal peptides (NRP) are a class of peptide secondary metabolites, usually produced by microorganisms like bacterium, bacteria and fungi. Nonribosomal peptides are also found in higher organisms, such as nudibranchs, but are thought to be made by bacteria commensalism, inside these organisms. While there exist a wide range of peptides that are not synthesized by ribosomes, the term ''nonribosomal peptide'' typically refers to a very specific set of these as discussed in this article. Nonribosomal peptides are synthesized by nonribosomal peptide synthetases, which, unlike the ribosomes, are independent of messenger RNA. Each nonribosomal peptide synthetase can synthesize only one type of peptide. Nonribosomal peptides often have cyclic compound, cyclic and/or branched structures, can contain non-proteinogenic amino acids including D-amino acids, carry modifications like ''Nitrogen, N''-methyl and ''N''-formyl groups, or are Glycosylation, glycosylated, Acylation, acylated, Ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acyl Carrier Protein Synthase
In enzymology and molecular biology, a holo- cyl-carrier-proteinsynthase (ACPS, ) is an enzyme that catalyzes the chemical reaction: :CoA- '-phosphopantetheine+ apo-acyl carrier protein \rightleftharpoons adenosine 3',5'-bisphosphate + holo-acyl carrier protein This enzyme belongs to the family of transferases, specifically those transferring non-standard substituted phosphate groups. It is also known as 4'-phosphopantetheinyl transferase after the group it transfers. Function All ACPS enzymes known so far are evolutionally related to each other in a single superfamily of proteins. It transfers a 4'-phosphopantetheine (4'-PP) moiety from coenzyme A (CoA) to an invariant serine in an acyl carrier protein (ACP), a small protein responsible for acyl group activation in fatty acid biosynthesis. This post-translational modification renders holo-ACP capable of acyl group activation via thioesterification of the cysteamine thiol of 4'-PP. This superfamily consists of two subtypes: th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphopantetheine
Phosphopantetheine, also known as 4'-phosphopantetheine, is a prosthetic group of several acyl carrier proteins including the acyl carrier proteins (ACP) of fatty acid synthases, ACPs of polyketide synthases, the peptidyl carrier proteins (PCP), as well as aryl carrier proteins (ArCP) of nonribosomal peptide synthetases (NRPS). It is also present in formyltetrahydrofolate dehydrogenase. Subsequent to the expression of the ''apo'' acyl carrier protein, 4'-phosphopantetheine moiety is attached to a serine residue. The coupling involves formation of a phosphodiester linkage. This coupling is mediated by acyl carrier protein synthase (ACPS), a 4'-phosphopantetheinyl transferase. Phosphopantetheine prosthetic group covalently links to the acyl group via a high energy thioester bond. The flexibility and length of the phosphopantetheine chain (approximately 2 nm) allows the covalently tethered intermediates to access spatially distinct enzyme-active sites. This accessibility ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Acid Synthase
Fatty acid synthase (FAS) is an enzyme that in humans is encoded by the ''FASN'' gene. Fatty acid synthase is a multi-enzyme protein that catalyzes fatty acid synthesis. It is not a single enzyme but a whole enzymatic system composed of two identical 272 kDa multifunctional polypeptides, in which Substrate (biochemistry), substrates are handed from one functional domain to the next. Its main function is to catalyze the synthesis of palmitic acid, palmitate (C16:0, a long-chain Saturated fat, saturated fatty acid) from acetyl-CoA and malonyl-CoA, in the presence of nicotinamide adenine dinucleotide phosphate, NADPH. The fatty acids are synthesized by a series of decarboxylative Claisen condensation reactions from acetyl-CoA and malonyl-CoA. Following each round of elongation the beta keto group is reduced to the fully saturated carbon chain by the sequential action of a Beta-Ketoacyl ACP reductase, ketoreductase (KR), dehydratase (DH), and Enoyl-acyl carrier protein reductase, e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyketide Synthase
Polyketide synthases (PKSs) are a family of multi- domain enzymes or enzyme complexes that produce polyketides, a large class of secondary metabolites, in bacteria, fungi, plants, and a few animal lineages. The biosyntheses of polyketides share striking similarities with fatty acid biosynthesis. The PKS genes for a certain polyketide are usually organized in one operon or in gene clusters. Type I and type II PKSs form either large modular protein complexes or dissociable molecular assemblies; type III PKSs exist as smaller homodimeric proteins. Classification PKSs can be classified into three types: * Type I PKSs are large, complex protein structures with multiple modules which in turn consist of several domains that are usually covalently connected to each other and fulfill different catalytic steps. The minimal composition of a type I PKS module consists of an acyltransferase (AT) domain, which is responsible for choosing the building block to be used, a keto synthase (KS) do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
