Glucose metabolism by Lactobacillus divergens.
Earlier studies on the fermentation of D-[1-14C]- and D-[3,4-14C]glucose by Lactobacillus divergens showed that lactate was the major fermentation product and that it was probably produced by glycolysis. It was therefore recommend that L. divergens be reclassified as a homofermentative organism. In the present investigation, products of D-[1-14C]-,D-[2-14C]- and D-[3,4-14C]glucose fermented by L. divergens were isolated, and their specific radioactivities and the distribution patterns of radioactivity in their C-atoms were determined. The positional labelling patterns of the fermentation products, their specific radioactivities and their concentrations confirmed that glucose is degraded via the glycolytic pathway. Some secondary decarboxylation/dissimilation of pyruvate to acetate, formate and CO2 was also observed. These results provide conclusive proof that L. divergens is indeed a homofermentative organism. Results obtained with D-[U-14C]glucose showed that approximately three-quarters of the lactate but less than 10% each of the formate and acetate were produced from glucose. The remainder was presumably derived to a varying degree from endogenous non-glucose sources such as fructose and/or amino acids.
De Bruyn
I N
IN
Department of Microbiology, University of Pretoria, Republic of South Africa.
Holzapfel
W H
WH
Visser
L
L
Louw
A I
AI
D000085:Acetates / Q000378:metabolism; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D007778:Lactobacillus / Q000378:metabolism*
D000085:Acetates; D007773:Lactates; D019344:Lactic Acid; D005947:Glucose