Oxygen dependent lactate utilization by Lactobacillus plantarum

Abstract

Lactobacillus plantarum P5 grew aerobically in rich media at the expense of lactate; no growth was observed in the absence of aeration. The oxygen-dependent growth was accompanied by the conversion of lactate to acetate which accumulated in the growth medium. Utilization of oxygen with lactate as substrate was observed in buffered suspensions of washed whole cells and in cell-free extracts. A pathway which accounts for the generation of adenosine triphosphate during aerobic metabolism of lactate to acetate via pyruvate and acetyl phosphate is proposed. Each of the enzyme activities involved, nicotinamide adenine dinucleotide independent lactic dehydrogenase, nicotinamide adenine dinucleotide dependent lactic dehydrogenase, pyruvate oxidase, acetate kinase and NADH oxidase were demonstrated in cell-free extracts. The production of pyruvate, acetyl phosphate and acetate was demonstrated using cell-free extracts and cofactors for the enzymes of the proposed pathway.

Sugar-glycerol cofermentations in lactobacilli: the fate of lactate

“…In L. plantarum, the enzyme catalyzing the conversion of lactate to pyruvate is an iLDH (EC 1.1.99) (17). We have found, by using both D-(-)-and L-(+)-lactates, that this activity was also present in our cell extracts, but only in those from cultures in which lactate was being metabolized (Tables 1 and 2).…”

“…In L. plantarum, the activities of the iLDH and pyruvate oxidase (EC 1.2.3.3) are together enhanced in the presence of oxygen and reduced in the presence of glucose (17,20,21). In L. brevis and L. buchneri, the activity of iLDH (Tables 1 and 2) was detected only in extracts from cultures cofermenting sugar and glycerol; the cultures without glycerol had no iLDH activity.…”

Energy production from L-malic acid degradation and protection against acidic external pH in Lactobacillus plantarum CECT 220

“…ATP production could be coupled to the formation of acetic acid which could be derived from lactic acid. In L. plantarum, lactate can be further degraded to pyruvic acid and acetic acid (Murphy et al, 1985;Lindgren et al, 1990). The present study cannot exclude either of these proposals.…”

Lactobacilles, oxygène, métabolisme et antagonisme

“…De plus, la détermination des activités est toujours faite sur des extraits et ne peut exclure la participation de la lactate deshydrogénase et de la pyruvate oxydase comme le soulignent Murphy et al (1985). Chez L plantarum, la lactate deshydrogé-nase NAD dépendante fonctionne essentiellement en faveur de la production de lactate.…”

“…-une NADH peroxydase : cette enzyme est une flavoprotéine, très répandue chez les bactéries lactiques; elle a été signalée également pour L plantarum ATCCa014 (Goetz et al,19aO) (Murphy et al, 1985). …”