0000000000329484
AUTHOR
Tanja Zaunmüller
Succinate dehydrogenase functioning by a reverse redox loop mechanism and fumarate reductase in sulphate-reducing bacteria.
Sulphate- or sulphur-reducing bacteria with known or draft genome sequences (Desulfovibrio vulgaris, Desulfovibrio desulfuricans G20, Desulfobacterium autotrophicum [draft], Desulfotalea psychrophila and Geobacter sulfurreducens) all contain sdhCAB or frdCAB gene clusters encoding succinate : quinone oxidoreductases. frdD or sdhD genes are missing. The presence and function of succinate dehydrogenase versus fumarate reductase was studied. Desulfovibrio desulfuricans (strain Essex 6) grew by fumarate respiration or by fumarate disproportionation, and contained fumarate reductase activity. Desulfovibrio vulgaris lacked fumarate respiration and contained succinate dehydrogenase activity. Succi…
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 of Sugars and Organic Acids by Lactic Acid Bacteria from Wine and Must
Heterofermentative lactic acid bacteria (LAB) which are common in plant associated environments are found also in grape must and wine. In this environment specific strains predominate which are adapted to the low pH and high alcohol contents. Must and wine harbour the strictly heterofermentative Oenococcus oeni, Lactobacillus hilgardii and Lactobacillus brevis, and the facultatively heterofermentative Lactobacillus plantarum and Lactobacillus pentosus (Rodas et al. 2005). In addition homofermentative lactic acid bacteria of the Pediococcus group are able to grow in wine and must, but are normally found at low cell densities. The growth of lactic acid bacteria in wine depends largely on suga…
Transport of Sugars and Sugar Alcohols by Lactic Acid Bacteria
Lactic acid bacteria (LAB) play an important role in the fermentation of beverages like wine and beer, and in the production of dairy products, sour dough, sausages and cheese. The knowledge of the genome sequence offers an insight into the metabolism of the bacteria and provides means to optimize the manufacturing of the products. By now genomes of several lactic acid bacteria are sequenced, including wine related bacteria Oenococcus oeni PSU-1, Pediococcus pentosaceus ATCC 25745, Leuconostoc mesenteroides ATCC 8293 (http://www.jgi.doe.gov/; Klaenhammer et al. 2002; Mills et al. 2005) and Lactobacillus plantarum WCFS1 (http://www.cmbi. ru.nl/plantarum/; http://www.lacplantcyc.nl/; Kleerebe…