of Escherichia coli mutants in central carbon metabolism using GC-MS. Eur J Biochem 2003,270(5):880–891f.PubMedCrossRef 79. Zamboni N, Fischer E, Sauer U: FiatFlux-a software for metabolic flux analysis from 13 C -glucose experiments. BMC Bioinformatics 2005, 6:209.PubMedCrossRef 80. Pramanik J, Keasling JD: Stoichiometric model of Escherichia coli metabolism: incorporation of growth-rate dependent biomass composition and mechanistic energy requirements. Biotechnol Bioeng 1997,56(4):398–421.PubMedCrossRef 81. Pramanik J, Keasling JD: Effect of Escherichia coli biomass composition on central metabolic fluxes predicted by a stoichiometric model. Biotechnol Bioeng 1998,60(2):230–238.PubMedCrossRef 82. Emmerling M, Dauner M, Ponti A, Fiaux J, Hochuli M, Szyperski T, Wüthrich K, Bailey JE, Sauer U: Metabolic selleck chemicals llc flux responses to pyruvate kinase knockout in Escherichia coli . J Bacteriol 2002, 184:152–164.PubMedCrossRef 83. Busby S, Ebright RH: Transcription activation by catabolite activator protein (CAP). J Mol Biol 1999,293(2):199–213.PubMedCrossRef Authors’ contributions HW and HM performed 13C-labeling experiments, HPLC and GC-MS analyses and flux analysis.
JB performed the benchtop bioreactor experiments and corresponding HPLC analyses and enzyme assays. MFM constructed the knock-out strains. HW and JB drafted the manuscript. JM revised the manuscript critically.
All authors read and approved the final manuscript.”
“Background The excessive and often inappropriate use of antibiotics leads to a continuous increase and spread of antibiotic resistance among bacteria, thus making it imperative to discover and carefully use new antibacterial substances . Bacteriocins are bacterial ribosomally synthesised proteinaceous MG-132 in vitro substances with strong antibacterial activity, excellent structural stability, low immunogenicity, while resistance does not develop frequently [2–4]. One general mechanism of action of bacteriocins involves pore formation in target cells leading to the leakage of small molecules and cell death [4, 5]. Bacteriocins from Gram positive bacteria can be grouped into three classes: class I which includes lantibiotics containing post-translationally modified amino acids such as lanthionine and dehydrated amino acids, class II non-lantibiotics, containing only common amino acids and class III containing bacteriocins with higher molecular mass (> 10 kDa) [2, 4]. Lantibiotics (class I) are divided into type A (elongated linear peptides) and type B (globular peptides) . Class II is subdivided into three subclasses, namely, class IIa (pediocin-like bacteriocins), class IIb (two-peptide bacteriocins) and class IIc (other one-peptide bacteriocins) .