Oxidative Stress and Oxygen Metabolism in Lactic Acid Bacteria
Yuji Yamamoto, Philippe Gaudu and Alexandra Gruss
from: Lactic Acid Bacteria and Bifidobacteria: Current Progress in Advanced Research (Edited by: Kenji Sonomoto and Atsushi Yokota). Caister Academic Press, U.K. (2011)
Lactic acid bacteria (LAB) are used industrially for their fermentation properties, and as such, have been generally regarded as anaerobic bacteria that contain neither a respiratory chain nor a catalase. However, most LAB can grow under aerobic conditions and consume molecular oxygen by unique flavoprotein oxidases. Some lactic acid bacteria, such as Enterococcus faecalis and Lactococcus lactis, construct a functional respiratory chain when a source of heme, an essential cofactor of cytochrome oxidases, is provided. Others, such as Lactobacillus plantarum and Streptococcus agalactiae, undergo respiration metabolism when both heme and a quinone are provided. These unique characteristics of LAB have been studied by biochemical approaches and more recently by molecular and genetic approaches. In this chapter, we present an overview of the unique features of oxygen metabolism and mechanisms of oxygen tolerance in LAB read more ...