Acetate oxidation through a modified citric acid cycle in Propionibacterium freudenreichii

Utilization of coenzyme A by Propionibacterium freudenreichii.

Humic acid reduction by propionibacterium freudenreichii and other fermenting bacteria

Iron-reducing bacteria have been reported to reduce humic acids and low-molecular-weight quinones with electrons from acetate or hydrogen oxidation. Due to the rapid chemical reaction of amorphous ferric iron with the reduced reaction products, humic acids and low-molecular-weight redox mediators may play an important role in biological iron reduction. Since many anaerobic bacteria that are not...

Lipase and Esterase Activities of Propionibacterium freudenreichii subsp. freudenreichii.

The lipase and esterase activities of eight strains of dairy Propionibacterium freudenreichii subsp. freudenreichii were studied. A lipase activity was detected on whole cells and in the culture supernatant. The highest activity was expressed at 45 degrees C and pH 6.8. An esterase activity was also detected in the culture medium. The electrophoresis of the intracellular fractions of the cells ...

Enhanced Propionate Formation by Propionibacterium freudenreichii subsp. freudenreichii in a Three-Electrode Amperometric Culture System.

In order to influence the fermentation pattern of Propionibacterium freudenreichii towards enhanced propionate formation, growth and product formation with glucose and lactate as energy sources were studied in a three-electrode poised-potential amperometric culture system. With anthraquinone 2,6-disulfonic acid (E(0)' = -184 mV; poised electron potential = -224 mV) or cobalt sepulchrate (E(0)' ...

Aminopeptidase activities of Propionibacterium freudenreichii dairy isolates

This study was undertaken to achieve more information on the aminopeptidase activities expressed in Propionibacterium freudenreichii strains naturally occurring in milk and dairy products. Fifty four strains belonging to both subspecies freudenreichii and shermanii were analyzed for activity towards different amino acyl β-naphthylamide (βNA) derivatives. The ability to efficiently hydrolyze ami...