Diverse effects of formate on the dissimilatory metabolism of nitrate in Pseudomonas denitrificans ATCC 13867: Growth,nitrite accumulation in culture,cellular activities of nitrate and nitrite reductases

The growth of Pseudomonas denitrificans ATCC 13867 under denitrifying conditions was significantly stimulated by adding an appropriate amount of formate (2.5 mM or above) to the growth medium. The accumulation of nitrite in the culture was markedly depressed so long as formate remained in the culture above a certain level. Cellular activities of enzymes participating in denitrification also changed. The cells grown in the presence of formate exhibited a lower nitrate reductase activity and, in contrast, a higher nitrite reductase activity than the cells grown without added formate.