Oxygen Relieves the CO2 and Acetate Dependency of Lactobacillus johnsonii NCC 533

Abstract

Oxygen relieves the CO2 and acetate dependency of Lactobacillus johnsonii NCC 533. The probiotic Lactobacillus johnsonii NCC 533 is relatively sensitive to oxidative stress; the presence of oxygen causes a lower biomass yield due to early growth stagnation. We show however that oxygen can also be beneficial to this organism as it relieves the requirement for acetate and CO2 during growth. Both on agar- and liquid-media, anaerobic growth of L. johnsonii NCC 533 requires CO2 supplementation of the gas phase. Switching off the CO2 supply induces growth arrest and cell death. The presence of molecular oxygen overcomes the CO2 dependency. Analogously, L. johnsonii NCC 533 strictly requires media with acetate to sustain anaerobic growth, although supplementation at a level that is 100-fold lower (120 microM) than the concentration in regular growth medium for lactobacilli already suffices for normal growth. Analogous to the CO2 requirement, oxygen supply relieves this acetate-dependency for growth. The L. johnsonii NCC 533 genome indicates that this organism lacks genes coding for pyruvate formate lyase (PFL) and pyruvate dehydrogenase (PDH), both CO2 and acetyl-CoA producing systems. Therefore, C1- and C2- compound production is predicted to largely depend on pyruvate oxidase activity (POX). This proposed role of POX in C2/C1-generation is corroborated by the observation that in a POX deficient mutant of L. johnsonii NCC 533, oxygen is not able to overcome acetate dependency nor does it relieve the CO2 dependency.

H 2 O 2 Production in Species of the Lactobacillus acidophilus Group: a Central Role for a Novel NADH-Dependent Flavin Reductase

“…It appears justified to conclude that the oxidative lactate utilization pathway is not responsible for the greater part of the H 2 O 2 production, suggesting that an alternative metabolic conversion may account for the H 2 O 2 production. This suggestion is in agreement with the previous observation that in the presence of oxygen, no substantial production and excretion of acetate occur (38).…”

“…The construction of the pox deletion strain NCC 9333 has been described previously (38). The deletion of the gene LJ_1826 encoding a predicted lactate oxidase enzyme was achieved similarly: the 5= homology region of the LJ_1826 gene was amplified from L. johnsonii NCC 533 genomic DNA using primers A and B.…”

Biochemical analysis of respiratory metabolism in the heterofermentativeLactobacillus spicheriandLactobacillus reuteri

“…The characterization of a pox deficient mutant of Lactobacillus johnsonii , however, suggested that pyruvate dehydrogenase supplies acetyl‐CoA and TPP to support anabolic metabolism, and is complemented or replaced by pyruvate oxidase at aerobic conditions (Hertzberger et al . ). This study demonstrated that pox is overexpressed in Lact.…”

“…lactis during growth under substrate limitation and microaerophilic conditions (Jensen et al 2001) and a pdhA deficient mutant of Streptococcus mutans displayed a decreased resistance to acid conditions (Korithoski et al 2008). The characterization of a pox deficient mutant of Lactobacillus johnsonii, however, suggested that pyruvate dehydrogenase supplies acetyl-CoA and TPP to support anabolic metabolism, and is complemented or replaced by pyruvate oxidase at aerobic conditions (Hertzberger et al 2013). This study demonstrated that pox is overexpressed in Lact.…”

Isolation and characterization of a CO2-tolerant Lactobacillus strain from Crystal Geyser, Utah, U.S.A.

“…While a large degree of attention has been given to these bacteria for food and disease studies, little has been given to their presence and environmental significance in the deep subsurface. Capnophiles may, for example, use CO 2 for metabolic processes such as in acetyl-CoA production, amino acid synthesis, or fermentation (e.g., Wynne and Foster, 1948;Maren, 1967;Smith and Ferry, 2000;Song et al, 2007;Arioli et al, 2009;Hertzberger et al, 2013).…”