Lactobacillus plantarum WCFS1 Electron Transport Chains

• Published in: Applied and Environmental Microbiology 2009-06, Vol.75 (11), p.3580-3585
• Main Authors: Brooijmans, R.J.W, de Vos, W.M, Hugenholtz, J
• Format: Article
• Language: English
• Subjects: Acidification; aerobic respiratory-chain; Aerobiosis; Ammonia - metabolism; Bacteria; Bacterial Proteins - metabolism; Bacteriology; Biological and medical sciences; coli nitrate reductase; Electron Transport; Electrons; escherichia-coli; Fundamental and applied biological sciences. Psychology; Gene Knockout Techniques; Gene Order; Genes, Bacterial; Glucose - metabolism; heme; Heme - metabolism; Lactobacillus plantarum; Lactobacillus plantarum - growth & development; Lactobacillus plantarum - metabolism; lactococcus-lactis; Mannitol - metabolism; metabolism; Microbiology; Nitrates; Nitrates - metabolism; nitrite; Nitrites - metabolism; Oxidation-Reduction; Oxygen; Oxygen - metabolism; Physiology; Respiration; site; terminal oxidase; translocation; Vitamin K 2 - metabolism
• ISSN: 0099-2240; 1098-5336; 1098-6596
• DOI: 10.1128/AEM.00147-09

Lactobacillus plantarum WCFS1 requires both heme and menaquinone to induce respiration-like behavior under aerobic conditions. The addition of these compounds enhanced both biomass production, without progressive acidification, and the oxygen consumption rate. When both heme and menaquinone were present, L. plantarum WCFS1 was also able to reduce nitrate. The ability to reduce nitrate was severely inhibited by the glucose levels that are typically found in L. plantarum growth media (1 to 2% [vol/vol] glucose). In contrast, comparable mannitol levels did not inhibit the reduction of nitrate. L. plantarum reduced nitrate with concomitant formation of nitrite and ammonia. Genes that encode a bd-type cytochrome (cydABCD) and a nitrate reductase (narGHJI) were identified in the genome of L. plantarum. The narGHJI operon is part of a cluster of genes that includes the molybdopterin cofactor biosynthesis genes and narK. Besides a menaquinone source, isogenic mutants revealed that cydA and ndh1 are required for the aerobic-respiration-like response and narG for nitrate reduction. The ndh1 mutant was still able to reduce nitrate. The existence of a nonredundant branched electron transport chain in L. plantarum WCFS1 that is capable of using oxygen or nitrate as a terminal electron acceptor is proposed.