During O2-free growth in the light and in medium with pyruvate, Rhodospirillum rubrum exhibits diauxic growth. The cells first fermented pyruvate and afterwards photometabolized. Exogenous cyclic AMP acted to prolong the lag period between fermentative and photosynthetic development, as well as to slow the light-dependent growth rate. This observation, and in situ changes in the cyclic AMP leve...

SpoU is encoded by the fourth open reading frame (ORF) of the spo operon of Escherichia coli (1). The 5'-terminal gene of this operon, gmk, encodes guanylate kinase; the second gene, rpoZ, encodes the w subunit of RNA polymerase; the third gene, spoT, encodes ppGpp hydrolase, and the 3'-terminal gene, recG, encodes a helicase-like protein involved in recombination (1 and references therein). Sp...

Calculations suggest that some carbon chemical shifts in proteins should have large ring current shifts (> 1 ppm). We present 13C, 15N and 1H assignments for cytochrome C2 from Rhodospirillum rubrum, compare these with shifts for other cytochromes c, and show that the calculated ring current shifts are similar to experimentally observed shifts, but that there remain substantial conformation-dep...

Several core light-harvesting complexes from both sulfur and non-sulfur purple photosynthetic bacteria have been identified to be methylated at the N-terminal alpha-amino group of beta-polypeptides by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and nuclear magnetic resonance. Monomethylation has been confirmed for the N-terminal alanine residues of the bet...

Isocitratase, which cleaves isocitrate to glyoxylate and succinate and is a key enzyme in the glyoxylate cycle, is formed by Rhodopseudomonas palustris and R. capsulatus when grown on acetate or butyrate either anaerobically in light or aerobically in the dark. Only traces of the enzyme are present in organisms grown on succinate or malate. In contrast, isocitratase is detectable in traces only...