Assessment of the metabolism of different strains of bacillus megaterium

Abstract

Bacillus megaterium is a promising host for expression of heterologous proteins. This paper reports the nutrient consumption patterns and production of metabolites for three different strains of B. megaterium, ATCC 14945, QMB 1551 and PV 361, which is QMB 1551 with seven constitutive plasmids deleted. 14 h cultivations in agitated flasks were run, for two different media: A (LB plus 10g/L glucose) and B (medium A, with the yeast extract replaced by tryptone). Strains PV361 and QMB 1551 showed higher maximum specific growth rates in medium B, reaching 0.42 h-1 and 0.48 h-1 respectively. The main by-products of the glucose overflow mechanism were acetate and lactate, for all three strains, which had preferential amino acids for substrate: Ala, Asp, Glu, Ser. No production of alcohols was detected.