Necessity of a membrane component for nitrogenase activity in Rhodospirillum rubrum.
Acetylene reduction catalyzed by nitrogenase from Rhodospirillum rubrum has low activity and exhibits a lag phase. The activity can be increased by the addition of a chromatophore membrane component and the lag eliminated by preincubation with this component, which can be solubilized from chromatophores by treatment with NaCl. It is both trypsin- and oxygen-sensitive. Titration of the membrane component with nitrogenase and vice versa shows a saturation point. The membrane component interacts specifically with the Fe protein of nitrogenase, the interaction being ATP- and Mg2+-dependent.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D002462:Cell Membrane / Q000201:enzymology; D004789:Enzyme Activation; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D008565:Membrane Proteins / Q000378:metabolism; D009591:Nitrogenase / Q000378:metabolism*; D012247:Rhodospirillum rubrum / Q000201:enzymology* / Q000648:ultrastructure; D012995:Solubility
D008565:Membrane Proteins; D000255:Adenosine Triphosphate; D009591:Nitrogenase; D008274:Magnesium