The glycogen accumulation in cells of Chlorobium limicola under the conditions of the disruption of some steps of the Arnon’ cycle

Abstract

Nitrates are not utilized by photosynthetic green sulfur bacteria Chlorobium limicola as the nitrogen source. Addition of these compounds into the medium inhibits the growth of bacteria but stimulates the glycogen accumulation. Nitrates are rapidly converted by the cells of C. limicola to the nitrites. Maximal nitrate reductase activity in the cells of C. limicola was detected after one day cultivation. Nitrates and nitrites inhibit activity of fumarase – the key enzyme of the reductive tricarboxylic acid cycle. Nitrites have more potential action as compared to the nitrate. The glycogen content in the cells of C. limicola cultivated in the medium with nitrates, but not acetate and pyruvate, show no significant change. Addition of acetate and pyruvate to the medium stimulate the glycogen synthesis in the presence of nitrate. Iodine acetate decreases the glycogen level under these conditions.

Keywords

• chlorobium limicola
• glycogen
• arnon’ cycle
• nitrates