Preparations from a variety of photosynthetic organisms carry out a light-dependent phosphorylation of adenosine diphosphate. These systems appear to be similar in one respect: photophosphorylation is stimulated by substances that may behave as reducing agents, or as electron carriers. In the present study, the photophosphorylation system in extracts of Rhodospirillum rubrum is found to be acti...

Homologs of ntrB and ntrC genes from Rhodospirillum rubrum were cloned and sequenced. A mutant lacking ntrBC was constructed, and this mutant has normal nitrogenase activity under nif-derepressing conditions, indicating that ntrBC are not necessary for the expression of the nif genes in R. rubrum. However, the post-translational regulation of nitrogenase activity by ADP-ribosylation in response...

From genomic libraries of the purple non-sulfur bacteria Rhodospirillum rubrum Ha and Rhodobacter sphaeroides ATCC 17023 in the broad-host range cosmid pVK100, we cloned a 15- and a 14-kbp HindIII restriction fragment, respectively. Each of these fragments restored the ability to accumulate poly(3-hydroxybutyrate) (PHB), in the PHB-negative mutant Alcaligenes eutrophus PHB-4. These hybrid cosmi...

Carbon monoxide (CO) has long been known to have dramatic physiological effects on organisms ranging from bacteria to humans, but recently there have a number of suggestions that organisms might have specific sensors for CO. This article reviews the current evidence for a variety of proteins with demonstrated or potential CO-sensing ability. Particular emphasis is placed on the molecular descri...

Liberated by enzymatic lysis of the cells, the flagella of Rhodospirillum rubrum, R. molischianum, and R. fulvum all have a similar structure. The hook at the base of the flagellum is connected by a short, narrow collar to a paired disc in the basal organelle. This paired disc is in turn connected to a second paired disc. The disposition of flagella to which fragments of the cell membrane still...

Transhydrogenase is a proton pump found in the membranes of bacteria and animal mitochondria. The solution structure of the expressed, 21.5 kDa, NADP(H)-binding component (dIII) of transhydrogenase from Rhodospirillum rubrum has been solved by NMR methods. This is the first description of the structure of dIII from a bacterial source. The protein adopts a Rossmann fold: an open, twisted, parall...

Survivability under carbon-starvation conditions was investigated in four species of purple phototrophic bacteria: Rhodopseudomonas palustris, Rhodobacter sphaeroides, Rhodospirillum rubrum, and Rubrivivax gelatinosus. All these test organisms survived longer in the light than in the dark. ATP levels in the cultures were maintained in the light, which indicated that survivability was supported ...

This paper describes some new characteristics of the phosphoenolpyruvate carboxykinase CO(2)-oxaloacetate exchange reaction in purified preparations of Rhodospirillum rubrum. The enzymatic activity has been purified 169-fold. Nucleotide diphosphates substitute for nucleotide triphosphates in the exchange reaction. Nucleotide diphosphates will not support the synthesis of phosphoenolpyruvate fro...

The light-induced cation radical of the primary electron donor, P(870) (+.), in photosynthetic reaction centers from Rhodospirillum rubrum G-9, has been investigated by electron-nuclear double resonance (ENDOR) in liquid aqueous solution. The measured hyperfine coupling constants are assigned to specific molecular positions by partial deuteration. Comparison with the bacteriochlorophyll a catio...