Bacteria phototrophic

Phototrophic Bacteria and Their Sulfur Metabolism (H. G. Triiper)... 

Obviously the redox poise in biological systems is very important and the movement of selenium through this process has been investigated for denitrifiers such as Paracoccus denitrificans,159 a specialized selenate-respiring bacterium Thauera selenatis which used selenate as the sole electron acceptor,160,161 and phototrophic bacteria which produced different reduced forms of selenium when amended with either selenite or selenate and even added insoluble elemental Se.162 As noted above, Andreesen has commented on the importance of redox active selenocysteines135 and Jacob et al.136 note the importance of the thioredoxin system to redox poise. 

Methylated organo-selenium has been determined by GC/MS or fluorine-induced chemiluminescence to determine DMSe, DMDSe, and DMSeS. This last compound, dimethyl selenenyl sulfide, was mistakenly identified as dimethyl selenone (CH3Se02CH3) in earlier work with bacteria.181,182 However, much recent work with many microorganisms have shown ample evidence of DMSeS production from Gram-negative bacteria,181,183 phototrophic bacteria,167,184 phytoplankton185 and in B. juncea detailed above. SPME with microwave-induce plasma atomic emission spectrometry was recently used to... 

J. F. Imhoff (2001) True marine and halophilic anoxygenic phototrophic bacteria. Arch. Microbiol., 176 243-254... 

The immediate application of phototrophic bacteria in biotechnological systems of H2 generation is not possible due to many scientific and technological problems. Some of them... 

Criss RE (1999) Principles of stable isotope distribution. Oxford Univ Press, New York Croal LR, Johnson CM, Beard BL, Newman DK (2004) Iron isotope fractionation by anoxygenic Fe(II)-phototrophic bacteria. Geochim Cosmochim Acta in press Duce RA, Tindale NW (1991) Atmospheric transport of iron and its deposition in the ocean. Limnol... 

McCarty, S., Chasteen, T., Marshall, M. et al. (1993) Phototrophic bacteria produce volatile, methylated sulfur and selenium compounds. FEMS Lett., 112, 93-8. 

In wetlands N2 fixation can occur in the water colnmn, in the aerobic water-soil interface, in the anaerobic soil bulk, in the rhizosphere, and on the leaves and stems of plants. Phototrophic bacteria in the water and at the water-soil interface are generally more important than non-photosynthetic, heterotrophic bacteria in the soil and on plant roots (Buresh et al, 1980 Roger 1996). The phototrophs comprise bacteria that are epiphytic on plants and cyanobacteria that are both free-living and epiphytic. A particularly favourable site for cyanobacteria is below the leaf surface of the water fern Azolla, which forms a very efficient symbiosis with the cyanobacterinm Anabaena azollae. This symbiosis and those in various leguminous plants have been exploited in traditional rice prodnction systems to sustain yields of 2 to 4 t ha of grain withont fertilizer for hnndreds of years. 

Heterotrophic and phototrophic bacteria on added straw 20-40 for 10 t straw... 

Sasikala, K., Ramana, C.V., Rao, PR., Kovacs, K.L. 1993. Anoxygenic phototrophic bacteria physiology and advances in hydrogen technology. Adv Appl Microbio 38 211-295. 

Biooxidation hy aerobic or microaerophilic bacteria binding with ferrous ions produced by iron-reducing bacteria biooxidation by phototrophic bacteria... 

Although many terrestrial herbicides may also control phototrophic bacteria (algae 67 - 70), several species of non-phototrophic bacteria, such as Streptomyces, are prolific producers of off-flavor metabolites (Table I). The growdi of non-phototrophic populations may be fostered by nutrients released fiom phototrophic populations exposed to herbicides (77), thereby limiting the potential effectiveness of adapting terrestrial herbicides for the control of off-flavor metabolite synthesis. 

Figure 1. Higher taxa of phototrophic bacteria (modified after (3) and (9)).

If phototrophic bacteria can utilize externally offered elemental sulfur as sole electron source, they will oxidize it directly to sulfate without the formation of any other sulfur intermediate (27.291. If only thiosulfate is available, Anoxyphotobacteria have two possibilities to metabolize it ... 

Sulfide oxidation by phototrophic bacteria is catalyzed by c-type cytochromes, flavocytochromes and even cytochrome c complexes (see 4.2). A heat-labile cytochrome c-550 of Thiocapsa roseopersicina is responsible for the oxidation of sulfide. The end product is elemental sulfur and it is assumed that this cytochrome might also catalyze the reverse reaction by reducing the intracellularly stored elemental sulfur to sulfide (4.9V... 

Elemental sulfur was also formed during sulfide oxidation by a cytochrome c-flavocytochrome c-552 complex in Chromatium vinosum (42). Flavocytochromes of different phototrophic bacteria act as sulfide cytochrome c reductases and there was one report that a flavocytochrome possessed even elemental sulfur reductase activity (see 4.9V All flavocytochromes examined so far are heat-labile and are reduced by sulfide forming thiosulfate under strictly anaerobic conditions (4.9V The small acidic cytochromes c-551 of Ectothiorhodospira halochloris and Ectothiorhodospira abdelmalekii. both located on the outside of the cell membrane, stimulated the velocity of sulfide... 

There are two possibilities to oxidize sulfite to sulfate in phototrophic bacteria ... 

If phototrophic bacteria possess a dissimilatory ATP-sulfurylase, they convert APS with pyrophosphate directly to ATP and sulfate, without the help of an additional enzyme. Such an enzyme is necessary, if the organisms like Chlorobium vibrioforme f. thiosulfatophilum (Table IV) contain only the ADP-sulfurylase, because this enzyme liberates only ADP and sulfate from APS in the presence of inorganic phosphate. In this case, the organisms gain one ATP molecule from 2 molecules of ADP. This reaction is catalyzed by adenylate kinase which converts 2 ADP into 1 ATP and 1 AMP (38). 

The results of this study demonstrate that the antenna and the reaction center of R rubrum differ in then-specificities of carotenoid binding. Thus, the microorganism follows in this respect the pattern of other related phototrophic bacteria (Cogdell and Thomber, 1979 Cogdell et al., 1976). Such difference suggests strongly that the functional role of the carotenoid in each type of photosynthetic complex has differential aspects of importance sufficient to impose distinctive structural requirements. The available information on... 

Masters, R. A., and Madigan, M. 1983. Nitrogen metabolism in the phototrophic bacteria Rhodocycluspurpureus and Rhodospirillum tenue. J. Bacteriol. 155, 222-227. 

Widdel, F., Schnell, S., Heising, S. et al. (1993). Ferrous oxidation by anoxygenic phototrophic bacteria. Nature, 362, 834-6. 

FCSD is a periplasmic enzyme found in a number of phototrophic bacteria, as well as in Paracoccus denitrificans, that catalyzes the oxidation of sulfide to elemental sulfur (Cusanovich et al., 1991 Wodara et al., 1997). FCSD from Chromatium vinosum is a 67kDa heterodimer consisting of a 46kDa flavoprotein subunit and a 21 kDa diheme cytochrome. The secondary electron acceptor is probably a cytochrome (Gray and Knaff, 1982). The FAD is bound covalently to the flavoprotein subunit via an 8-a-methyl(S-cysteinyl) thioether linkage. 

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