Comparative study on central metabolic fluxes of Bacillus megaterium strains in continuous culture using 13C labelled substrates.

Fluxes of central carbon metabolism [glycolysis, pentose phosphate pathway (PPP), tricarboxylic acid cycle (TCA cycle), biomass formation] were determined for several Bacillus megaterium strains (DSM319, WH320, WH323, MS941) in C- and N-limited chemostat cultures by (13)C labelling experiments. The labelling patterns of proteinogenic amino acids were analysed by GC/MS and therefrom flux ratios at important nodes within the metabolic network could be calculated. On the basis of a stoichiometric metabolic model flux distributions were estimated for the different B.

Comparative proteomic analysis of high cell density cultivations with two recombinant Bacillus megaterium strains for the production of a heterologous dextransucrase.

High cell density cultivations were performed under identical conditions for two Bacillus megaterium strains (MS941 and WH320), both carrying a heterologous dextransucrase (dsrS) gene under the control of the xylA promoter. At characteristic points of the cultivations (end of batch, initial feeding, before and after induction) the proteome was analyzed based on two dimensional gel electrophoresis and mass spectrometric protein identification using the protein database "bmegMEC.v2" recently made available.

Proteomic characterization of transient expression and secretion of a stress-related metalloprotease in high cell density culture of Bacillus megaterium.

Intracellular and extracellular proteome analysis was carried out by combined two-dimensional gel electrophoresis and mass spectrometric analysis (2DE/MS) for high cell density fed-batch culture of recombinant Bacillus megaterium strains. In the early feeding phase with a constant growth rate of 0.12h(-1) under glucose limitation, high expression and secretion of a metalloprotease (referred as Bmg1465) was detected.

Proteome analysis of a recombinant Bacillus megaterium strain during heterologous production of a glucosyltransferase.

A recombinant B. megaterium strain was used for the heterologous production of a glucosyltransferase (dextransucrase). To better understand the physiological and metabolic responses of the host cell to cultivation and induction conditions, proteomic analysis was carried out by combined use of two-dimensional gel electrophoresis and mass spectrometry (2-DE/MS) for protein separation and identification.

Production and secretion of recombinant Leuconostoc mesenteroides dextransucrase DsrS in Bacillus megaterium.

Leuconostoc mesenteroides dextransucrase DsrS was recombinantly produced in Bacillus megaterium and exported into the growth medium. For this purpose a plasmid-based xylose-inducible gene expression system was optimized via introduction of a multiple cloning site and an encoded optimal B. megaterium ribosome binding site.

Pyruvate formation and suppression in recombinant Bacillus megaterium cultivation.

A recombinant Bacillus megaterium strain showed the ability to secrete large amounts of pyruvate (up to 27.8 gl( -1)) for growth rates larger than 0.15 h(-1).