Heme-dependent catalase activity of lactobacilli.

The heme-dependent catalase in Lactobacillus pentosus, L. sake, L. delbrueckii and Enterococcus faecalis was studied. The catalase was formed by cells grown aerobically in the presence of hematin or for lactobacilli when grown without added hematin, after incubation of buffered cells in the presence of hematin. The kinetics of the production of catalase revealed maximum activity for L. pentosus and E. faecalis at late stationary and late logarithmic growth phase, respectively. The physiological role of catalase was studied with L. sake. The presence of hematin allows higher growth yields, since it protects the cells against hydrogen peroxide formed endogenously up to concentrations of 4.6 mmol/l.