Anaerobic adaptation ofParacoccus denitrificans: Sequential formation of denitrification pathway and changes in activity of 5-aminolevulinate synthase and catalase

Aerobically grown cells ofParacoccus denitrificans exhibited a marked increase in the activity of 5-aminolevulinate synthase in the early stage of adaptation to the decreased aeration of the growth medium. The effect was dependent on the functional proteosynthesis; it was not influenced by the presence of nitrate in the medium. An enhancement of nitrate reductase activity could be observed simultaneously; the rise of soluble cytochromec content was somewhat retarded. A significant lag phase of about 1 h appeared in the formation of nitrite reductase, which coincided with the shap drop in the catalase activity of the bacterium.