Peptide ribosomal

Moffitt, M. C. Neilan, B. A. The expansion of mechanistic and organismic diversity associated with non-ribosomal peptides. FEMS Microbiol Lett. 2000, 191, 159-167. 

Ku, J., Mirmira, R.G., Liu, L. andSanti, D.V. (1997) Expression of a functional non-ribosomal peptide synthetase module in Escherichia coli by coexpression with a phosphopantetheinyl transferase. Chemistry Biology, 4 (3), 203-207. 

Bacitracin biosynthesis requires a non-ribosomal peptide synthetase with three major protein components, BacABC. This synthetase has a modular structure. There are associated regulatory and transport systems. Biosynthesis of bacitracin has been engineered in the surrogate host, B. subtilis, by genetic techniques. A strain, B. subtilis KE 350, expresses the entire 49-kb bacitracin... 

In the field of fresh water plankton chemical ecology microcystins from cyanobacteria have stimulated much research and discussion. A critical reflection on the ecological function of these non-ribosomal peptides has recently been published (Babica et al. 2006). Surveys of methods for the quantification of these peptides (McElhiney and Lawton 2005 Msagati et al. 2006) and on the effects on fish (Malbrouck and Kestemont 2006) can be found as well. 

The amino acid components of proteins have the L conhguration (see Section 3.4.10), but many peptides are known that contain one or more D-amino acids in their stmctures. o-Amino acids are not encoded by DNA, and peptides containing them are produced by what is termed non-ribosomal peptide biosynthesis (see Section 13.5.2). o-Amino acids generally arise by epimerization of L-amino acids (see Box 10.10). All the protein L-amino acids have the S conhguration, except for glycine, which is not chiral, and L-methionine which is R, a consequence of the priority mles for systematic descriptors of conhguration (see Section 3.4.10). 

Peptides are produced in nature by one of two methods, termed ribosomal peptide biosynthesis... 

ACV is produced by the modular system for non-ribosomal peptide biosynthesis. The amino acid precursors are L-a-aminoadipic acid (an unusual amino acid derived by modification of L-lysine), L-cysteine, and L-valine during tripeptide formation, the L-valine is epimerized to o-valine (see Box 10.10). 

Antibiotics that interfere with ribosomal peptide biosynthesis... 

Tanaka A et al., A symbiosis expressed non-ribosomal peptide synthetase from a mutualistic fungal endophyte of perennial ryegrass confers protection to the symbiotum from insect herbivory, Mol Microbiol 57 1036—1050, 2005. 

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