Vacuum ultraviolet photodissociation of peptide ions in a matrix assisted laser desorption ionization (MALDI) tandem time-of-flight (TOF) mass spectrometer is used to characterize peptide mixtures derived from Deinococcus radiodurans ribosomal proteins. Tryptic peptides from 52 proteins were separated by reverse-phase liquid chromatography and spotted onto a MALDI plate. From 192 sample spots, ...

A total of 223 complete bacterial genomes are analyzed, with 281 citations, for the presence of genes encoding modular polyketide synthases (PKS) and nonribosomal peptide synthetases (NRPS). We report on the distribution of these systems in different bacterial taxa and, whenever known, the metabolites they synthesize. We also highlight, in the different bacterial lineages, the PKS and NRPS gene...

The Escherichia coli siderophore enterobactin is assembled from 2,3-dihydroxybenzoate (2,3-DHB) and l-serine by the nonribosomal peptide synthetases EntB and EntF. The processive thiol-template strategy used can be sabotaged by EntB misacylation. Through in vitro kinetic analysis, we demonstrate two potential routes to EntB misacylation and provide evidence for two mechanisms by which the hot d...

We describe a general strategy for selective chemical labeling of individual adenylation (A) domains in nonribosomal peptide synthetases (NRPSs) using active site-directed proteomic probes coupled to the 5'-O-N-(aminoacyl)sulfamoyladenosine (AMS) scaffold with a clickable benzophenone functionality. These proteomic tools can greatly facilitate the molecular identification, functional characteri...

Protein dynamics plays an important role in protein function. Many functionally important motions occur on the microsecond and low millisecond time scale and can be characterized by nuclear magnetic resonance relaxation experiments. We describe the different states of a peptidyl carrier protein (PCP) that play a crucial role in its function as a peptide shuttle in the nonribosomal peptide synth...

Non-ribosomally formed peptides display both highly conserved and variable amino acid positions, the variations leading to a wide range of peptide families. Activation of the amino acid substrate proceeds in analogy to the ribosomal biosynthetic mechanism generating aminoacyl adenylate and acyl intermediates. To approach the mechanism of fidelity of amino acid selection, the stability of the am...