%0 Journal Article %A Shaw, Brian D. %T Non-coordinate Regulation of Rhizobium Nitrogenase Synthesis by Oxygen: Studies with Bacteroids from Nodulated Lupinus angustifolius %D 1983 %J Microbiology, %V 129 %N 3 %P 849-857 %@ 1465-2080 %R https://doi.org/10.1099/00221287-129-3-849 %I Microbiology Society, %X Experimental conditions which allowed liquid suspensions of lupin bacteroids (Rhizobium NZP 2257) to reduce acetylene at high rates were established. At a dissolved oxygen concentration of 2 μm, swirled suspensions of the bacteroids reduced acetylene at a linear rate of 23 ± 5 nmol (mg cell protein)−1 min−1. The kinetics of protein synthesis were measured by pulse labelling with [35S]methionine followed by two-dimensional electrophoretic analysis of cell lysates. When the suspensions were suddenly exposed to air, the rate of synthesis of the two nitrogenase components declined differentially. The decline in the rate of synthesis of the Fe-protein polypeptides resembled that observed for all the nitrogenase polypeptides in Klebsiella pneumoniae ( Eady et al., 1978 ); the rate of synthesis of the MoFe-protein polypeptides, however, showed a much slower decline. Several models are proposed to account for these results. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-129-3-849