Significance of pantothenate for glucose fermentation by Oenococcus oeni and for suppression of the erythritol and acetate production.
The heterofermentative lactic acid bacterium Oenococcus oeni requires pantothenic acid for growth. In the presence of sufficient pantothenic acid, glucose was converted by heterolactic fermentation stoichiometrically to lactate, ethanol and CO2. Under pantothenic acid limitation, substantial amounts of erythritol, acetate and glycerol were produced by growing and resting bacteria. Production of erythritol and glycerol was required to compensate for the decreasing ethanol production and to enable the synthesis of acetate. In ribose fermentation, there were no shifts in the fermentation pattern in response to pantothenate supply. In the presence of pantothenate, growing O. oeni contained at l…
Role of secondary transporters and phosphotransferase systems in glucose transport by Oenococcus oeni.
ABSTRACT Glucose uptake by the heterofermentative lactic acid bacterium Oenococcus oeni B1 was studied at the physiological and gene expression levels. Glucose- or fructose-grown bacteria catalyzed uptake of [ 14 C]glucose over a pH range from pH 4 to 9, with maxima at pHs 5.5 and 7. Uptake occurred in two-step kinetics in a high- and low-affinity reaction. The high-affinity uptake followed Michaelis-Menten kinetics and required energization. It accumulated the radioactivity of glucose by a factor of 55 within the bacteria. A large portion (about 80%) of the uptake of glucose was inhibited by protonophores and ionophores. Uptake of the glucose at neutral pH was not sensitive to degradation …
Metabolism and Transport of Sugars and Organic Acids by Lactic Acid Bacteria from Wine and Must
Oenococcus oeni and other heterofermentative lactic acid bacteria from wine are able to grow at the expense of hexose and pentose sugars using the phosphoketolase pathway. Fermentation of hexoses is limited by low activity of the enzymes for ethanol production. Erythritol is formed as an alternative product, but the enzymes of the pathway are mostly unknown. Presence of fructose, citrate, pyruvate or O2 results in a shift of hexose fermentation to acetate at the expense of ethanol. O. oeni and other lactic acid bacteria are able to degrade organic acids of wine such as citrate, l-malate, pyruvate, l-tartrate and fumarate. The pathways for tartrate and fumarate degradation are known only in …
Pyruvate fermentation by Oenococcus oeni and Leuconostoc mesenteroides and role of pyruvate dehydrogenase in anaerobic fermentation.
ABSTRACT The heterofermentative lactic acid bacteria Oenococcus oeni and Leuconostoc mesenteroides are able to grow by fermentation of pyruvate as the carbon source (2 pyruvate → 1 lactate + 1 acetate + 1 CO 2 ). The growth yields amount to 4.0 and 5.3 g (dry weight)/mol of pyruvate, respectively, suggesting formation of 0.5 mol ATP/mol pyruvate. Pyruvate is oxidatively decarboxylated by pyruvate dehydrogenase to acetyl coenzyme A, which is then converted to acetate, yielding 1 mol of ATP. For NADH reoxidation, one further pyruvate molecule is reduced to lactate. The enzymes of the pathway were present after growth on pyruvate, and genome analysis showed the presence of the corresponding st…