This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Tseng, C P Articles by Montville, T J Search for Related Content PubMed PubMed Citation Articles by Tseng, C P Articles by Montville, T J

 Previous Article  |  Next Article 

J Bacteriol. 1991 July; 173(14): 4411-4416

research-article

Bioenergetic consequences of catabolic shifts by Lactobacillus plantarum in response to shifts in environmental oxygen and pH in chemostat cultures.

C P Tseng, J L Tsau and T J Montville

Graduate Program in Microbiology, New Jersey Agricultural Experiment Station, Cook College, Rutgers-State University, New Brunswick 08903.

ABSTRACT

Proton motive force (PMF), intracellular end product concentrations, and ATP levels were determined when a steady-state Lactobacillus plantarum 8014 anaerobic chemostat culture was shifted to an aerobic condition or was shifted from pH 5.5 to 7.5. The PMF and intracellular ATP levels increased immediately after the culture was shifted from anaerobic to aerobic conditions. The concentrations of intracellular lactate and acetate, which exported protons that contributed to the proton gradient, changed in the same fashion. The H+/lactate stoichiometry, n, varied from 0.8 to 1.2, and the H+/acetate n value changed from 0.8 to 1.6 at 2 h after the shift to aerobic conditions. The n value for acetate excretion remained elevated at aerobic steady state. When the anaerobic culture was shifted from pH 5.5 to 7.5, intracellular ATP increased 20% immediately even though the PMF decreased 50% as a result of the depletion of the transmembrane proton gradient. The H+/lactate n value changed from 0.7 to 1.8, and n for H+/acetate increased from 0.9 to 1.9 at pH 7.5 steady state. In addition, the H+/acetate stoichiometry was always higher than the n value for H+/lactate; both were higher in alkaline than aerobic conditions, demonstrating that L. plantarum 8014 coexcreted more protons with end products to maintain intracellular pH homeostasis and generate proton gradients under aerobic and alkaline conditions. During the transient to pH 7.5, the n value for H+/acetate approached 3, which would spare one ATP.

---

J Bacteriol. 1991 July; 173(14): 4411-4416

This article has been cited by other articles:

• Barthelmebs, L., Divies, C., Cavin, J.-F. (2000). Knockout of the p-Coumarate Decarboxylase Gene from Lactobacillus plantarum Reveals the Existence of Two Other Inducible Enzymatic Activities Involved in Phenolic Acid Metabolism. Appl. Environ. Microbiol. 66: 3368-3375 [Abstract] [Full Text]