Anaerobic fermentation of Salmonella typhimurium with and without pyruvatecarboxylase

Citation
L. Xie et al., Anaerobic fermentation of Salmonella typhimurium with and without pyruvatecarboxylase, BIOTECH LET, 23(2), 2001, pp. 111-117
Citations number
16
Categorie Soggetti
Biotecnology & Applied Microbiology",Microbiology
Journal title
BIOTECHNOLOGY LETTERS
ISSN journal
01415492 → ACNP
Volume
23
Issue
2
Year of publication
2001
Pages
111 - 117
Database
ISI
SICI code
0141-5492(200101)23:2<111:AFOSTW>2.0.ZU;2-S
Abstract
A plasmid that expressed pyruvate carboxylase (PYC) from Rhizobium etli was introduced into Salmonella typhimurium LT2. Anaerobic fermentations of S. typhimurium with and without PYC were compared with glucose as a carbon sou rce. The presence of PYC increased the succinate yield from glucose from 0. 044 g g(-1) to 0.22 g g(-1), while the lactate yield decreased from 0.31 g g(-1) to 0.16 g g(-1). Metabolic flux calculations during the early growth phase indicate that under these growth conditions in the presence of PYC mo re carbon flows to oxaloacetate via pyruvate carboxylase than via phosphoen olpyruvate carboxylase. Also, under these growth and induction conditions, the presence of PYC diminished the cell growth rate from 0.34 h(-1) to 0.28 h(-1), the specific rate of ATP formation from 45 mmol l(-1) h(-1) to 27 m mol l(-1) h(-1), and the specific rate of glucose consumption from 17 mmol l(-1) h(-1) to 10 mmol l(-1) h(-1).