Kinetic Analysis of Bifidobacterial Metabolism Reveals a Minor Role for Succinic Acid in the Regeneration of NAD ⁺ through Its Growth-Associated Production

Abstract

Several strains belonging to the genus Bifidobacterium were tested to determine their abilities to produce succinic acid. Bifidobacterium longum strain BB536 and Bifidobacterium animalis subsp. lactis strain Bb 12 were kinetically analyzed in detail using in vitro fermentations to obtain more insight into the metabolism and production of succinic acid by bifidobacteria. Changes in end product formation in strains of Bifidobacterium could be related to the specific rate of sugar consumption. When the specific sugar consumption rate increased, relatively more lactic acid and less acetic acid, formic acid, and ethanol were produced, and vice versa. All Bifidobacterium strains tested produced small amounts of succinic acid; the concentrations were not more than a few millimolar. Succinic acid production was found to be associated with growth and stopped when the energy source was depleted. The production of succinic acid contributed to regeneration of a small part of the NAD ؉ , in addition to the regeneration through the production of lactic acid and ethanol.

Mutual Cross-Feeding Interactions between Bifidobacterium longum subsp. longum NCC2705 and Eubacterium rectale ATCC 33656 Explain the Bifidogenic and Butyrogenic Effects of Arabinoxylan Oligosaccharides

“…Indeed, in Bifidobacterium spp., pyruvate can be converted into formate, acetate, and ethanol (Fig. 4), at the expense of lactate, to respond to a higher energy demand when growing on complex carbohydrates, which results in a lower growth rate and a shift from lactate production to mixed acid production (12,37,(50)(51)(52). The production of additional ethanol allowed the B. longum strain to regenerate more NAD ϩ , which is important for continuation of the upper pathways.…”

Diverse galactooligosaccharides consumption by bifidobacteria: implications of β-galactosidase—LacS operon

“…It is well known that bifidobacteria metabolize carbohydrates in the fructose-6-phosphate phosphoketolase (F6PK) pathway-the so called "bifidus shunt" [20][21][22][23][24] and convert substrates to organic acids such as acetate, lactate, and formate (Fig. S1).…”

Differentiation of species of the family Acetobacteraceae by AFLP DNA fingerprinting: Gluconacetobacter kombuchae is a later heterotypic synonym of Gluconacetobacter hansenii

“…These three strains (LMG 1524, LMG 1527 T and LMG 1528) as well as Gluconacetobacter kombuchae LMG 23726 T , were investigated for the phenotypic characteristics that have been reported to enable differentiation of both these species from the other species of the Gluconacetobacter xylinus branch. The production of 2-keto-D-gluconic acid and 5-keto-D-gluconic acid from D-glucose was determined by the method described by Gosselé et al (1980) using high pressure anion-exchange chromatography with conductivity detection under ion suppression (Van der Meulen et al, 2006) instead of TLC. Growth on the carbon sources ethanol, sucrose, sorbitol and D-mannitol; growth in the presence of 30 % D-glucose; production of acid from galactitol, and production of cellulose were examined by previously reported methods (Cleenwerck et al, 2002;Lisdiyanti et al, 2006).…”