Sulfide induction of synthesis of a periplasmic protein in the cyanobacterium Oscillatoria limnetica

Abstract

Two proteins which may play a role in the induction of anoxygenic photosynthesis in Oscillatoria limnetica have been demonstrated by comparing the pattern of labeling during pulses of [35S]methionine of cells incubated under inducing conditions [anaerobic conditions plus 3-(3,4-dichlorophenyl)-1,1-dimethylurea, light, and sulfide) with that of cells incubated under noninducing conditions (without sulfide). The major inducible protein has an apparent molecular mass of 11.5 kilodaltons and is associated with a less strongly labeled 12.5-kilodalton protein. The synthesis of both proteins commences within the first 30 min of induction and continues throughout the 2-h induction period. Since these proteins are not synthesized in the presence of dithionite without sulfide, low redox potential alone is insufficient as an inducer of these proteins. Lysozyme treatment and/or osmotic shock of intact cells results in the release of the sulfide-induced proteins. Our data thus indicate that these proteins are located in the periplasmic space of the cells.

Coregulated Genes Link Sulfide:Quinone Oxidoreductase and Arsenic Metabolism in Synechocystis sp. Strain PCC6803

“…Cyanobacteria gain ATP via photophosphorylation in oxygenic photosynthesis, but in the presence of sulfide the photosystem II (PSII) reaction center is inhibited (11). Nonetheless, besides green and purple sulfur bacteria, which drive photosynthesis using electrons from sulfide, some purple nonsulfur bacteria such as Rhodobacter capsulatus (12), some extremophile microorganisms and even a few strains of cyanobacteria contain SQR enzymes by which they can shift to anoxygenic, sulfur bacterium-type photosynthesis using sulfide as an electron donor, thus overcoming the deleterious effect of this compound.…”

Growth of Anacystis in the Presence of Thiosulphate and its Consequences for the Architecture of the Photosynthetic Apparatus

“…Not unlike other procaryotic organisms, such as thiobacilli (Oh and Suzuki, 1977a, b;Lu and Kelly, 1983) and phototrophic bacteria (Kusai and Yamanaka, 1973;Appelt et al, 1979;Steinmetz and Fischer, 1985). several cyanobacteria were shown to oxidize inorganic sulphur-containing compounds to sulphate or sulphur: Oscillatoria limnetica uses sulphide as electron donor for PSI (Padan, 1979;Padan and Cohen, 1982;Cohen et al, 1986;Belkin et al, 1988;Arieli et al, 1989;Slooten et al, 1989), and for Anacystis nidulans Utkilen (1976) showed the light dependent oxidation of thiosulphate to sulphate under aerobic conditions, in a reaction which was uninfluenced by DCMU but inhibited by DBMIB. Moreover, Oren and Padan (1978) demonstrated that anoxygenic photosynthesis is inducible in cyanobacteria and can be prevented by inhibitors of protein synthesis.…”

“…Consequently, it should be possible to trace a protein responsible for the oxidation of inorganic sulphur containing compounds. For Oscillatoria limnetica two low molecular weight periplasmic proteins have recently been demonstrated to be induced under conditions of sulphide oxidation in the absence of oxygen (Arieli et al, 1989). In case of thiosulphate oxidation by Anacystis, one could expect similarities to the enzyme complexes with corresponding function in thiobacilli or phototrophic bacteria.…”

Szulfid és arzén alapú alternatív anyagcsereutak tanulmányozása a Synechocystis sp. PCC6803 cianobaktériumban

“…Az oxidatív foszforilációt gátló hatása mellett reaktív gyököket is képez. Cianobaktériumokban pedig kimutatták, hogy a hidrogén-szulfid gátolja a PSII fotokémiai rendszert (46 A másik SQR gén a pSYSM plazmidon helyezkedik el és az I.-típusú SQR-ekkel mutat nagyfokú hasonlóságot (10,64). Mivel ez utóbbi jellemző a cianboktériumokra, munkánk során arra kívántunk fényt deríteni, hogy vajon képes-e a Synechocystis a SuoS révén egy szulfid bontáson alapuló alternatív fotoszintézisre.…”

“…Cohen, Arieli, Shahak és Oren (10,11,37,38,46,47,(68)(69)(70)(71)130) kutatásai alapján az 1970-es évek óta ismert, hogy a redukált kén elektronforrásként szolgálhat az oxigenikus fotoszintézist folytató cianobaktériumok számára is. Azonban az, hogy a kimondottan toxikusnak vélt arzén is hozzájárulhat anabolikus folyamatokhoz, rendkívüli felfedezésnek számított (3,145).…”