The reactive thioester complexes of gramicidin S synthetase with substrate amino acids and intermediate peptides are slowly hydrolyzed in neutral buffer solutions under mild conditions. Fully active enzyme is recovered. These processes are strongly accelerated by certain thiol protective agents. In the presence of 1 mM dithioerythritol the half-life times of these hydrolysis reactions are in the range of 1-90 h at 3 degrees C. The thioester complex of gramicidin S synthetase 2 (GS2, the heavy enzyme) with the tripeptide DPhe-Pro-Val is distinguished by the highest stability of all these intermediates. A different decomposition pattern is observed for the thioester complex of GS2 with LOrn. Here 3-amino-2-piperidone (cyclo-LOrn) is formed in a rapid cyclization reaction. This product specifically blocks the activation center of GS2 for LOrn at the thioester binding site. All other activation reactions of gramicidin S synthetase are unaffected. A procedure for a specific labelling of the reaction centers of the multienzyme is outlined.
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http://dx.doi.org/10.1111/j.1432-1033.1983.tb07352.x | DOI Listing |
Bioorg Med Chem
August 2024
Faculty of Pharmacy, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan. Electronic address:
J Am Chem Soc
June 2024
Department of Chemistry, Faculty of Natural, Mathematical, and Engineering Sciences, King's College London, Britannia House, 7 Trinity Street, London SE1 1DB, U.K.
Nonribosomal cyclic peptides (NRcPs) are structurally complex natural products and a vital pool of therapeutics, particularly antibiotics. Their structural diversity arises from the ability of the multidomain enzyme assembly lines, nonribosomal peptide synthetases (NRPSs), to utilize bespoke nonproteinogenic amino acids, modify the linear peptide during elongation, and catalyze an array of cyclization modes, e.g.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
May 2024
Institute of Biochemistry, Department of Chemistry and Pharmacy, University of Münster, Corrensstraße 36, 48149, Münster, Germany.
In multi-domain nonribosomal peptide synthetases (NRPSs) the order of domains and their catalytic specificities dictate the structure of the peptide product. Peptidyl-carrier proteins (PCPs) bind activated amino acids and channel elongating peptidyl intermediates along the protein template. To this end, fine-tuned interactions with the catalytic domains and large-scale PCP translocations are necessary.
View Article and Find Full Text PDFBeilstein J Org Chem
February 2024
Faculty of Pharmacy, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan.
The adenylation (A) domain is essential for non-ribosomal peptide synthetases (NRPSs), which synthesize various peptide-based natural products, including virulence factors, such as siderophores and genotoxins. Hence, the inhibition of A-domains could attenuate the virulence of pathogens. 5'---(Aminoacyl or arylacyl)sulfamoyladenosine (AA-AMS) is a bisubstrate small-molecule inhibitor of the A-domains of NRPSs.
View Article and Find Full Text PDFNat Chem
February 2024
Department of Chemistry, Princeton University, Princeton, NJ, USA.
Many peptide-derived natural products are produced by non-ribosomal peptide synthetases (NRPSs) in an assembly-line fashion. Each amino acid is coupled to a designated peptidyl carrier protein (PCP) through two distinct reactions catalysed sequentially by the single active site of the adenylation domain (A-domain). Accumulating evidence suggests that large-amplitude structural changes occur in different NRPS states; yet how these molecular machines orchestrate such biochemical sequences has remained elusive.
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