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Top-down mass spectrometry on low-resolution instruments: characterization of phosphopantetheinylated carrier domains in polyketide and non-ribosomal biosynthetic pathways.

ABSTRACT: Mass spectrometry (MS) is an important tool for studying non-ribosomal peptide, polyketide, and fatty acid biosynthesis. Here we describe a new approach using multi-stage tandem MS on a common ion trap instrument to obtain high-resolution measurements of the masses of substrates and intermediates bound to phosphopantetheinylated (holo) carrier proteins. In particular, we report the chemical formulas of 12 diagnostic MS(3) fragments of the phosphopantetheine moiety ejected from holo carrier proteins during MS(2). We demonstrate our method by observing the formation of holo-AcpC, a putative acyl carrier protein from Streptococcus agalactiae.

SUBMITTER: Meluzzi D

PROVIDER: S-EPMC2519147 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Top-down mass spectrometry on low-resolution instruments: characterization of phosphopantetheinylated carrier domains in polyketide and non-ribosomal biosynthetic pathways.

Meluzzi Dario D Zheng Wei Hao WH Hensler Mary M Nizet Victor V Dorrestein Pieter C PC

Bioorganic & medicinal chemistry letters 20071101 10

Mass spectrometry (MS) is an important tool for studying non-ribosomal peptide, polyketide, and fatty acid biosynthesis. Here we describe a new approach using multi-stage tandem MS on a common ion trap instrument to obtain high-resolution measurements of the masses of substrates and intermediates bound to phosphopantetheinylated (holo) carrier proteins. In particular, we report the chemical formulas of 12 diagnostic MS(3) fragments of the phosphopantetheine moiety ejected from holo carrier prote ...[more]

PMID: 18006314

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