Nonsulfur bacteria

Novak RT, RF Gritzer, ER Leadbetter, W Godchaux (2004) Phototrophic utilization of taurine by the purple nonsulfur bacteria Rhodopseudomonas palustris and Rhodobacter sphaeroides. Microbiology (UK) 150 1881-1891. 

Aside from C. vinosum, type III-PHA synthases have so far been detected exclusively in the phototrophic purple sulfur bacteria such as Thiocystis viol-acea [51] and Thiocapsa pfennigii [26, 57] and in cyanobacteria such as Synechocystis sp. PCC6803 [49] or Synechococcus sp. MAI 9 [58]. In contrast, the photosynthetic nonsulfur purple bacteria possess type I-PHA synthases. 

The photosynthetic reaction center (RC) of purple nonsulfur bacteria is the core molecular assembly, located in a membrane of the bacteria, that initiates a series of electron transfer reactions subsequent to energy transfer events. The bacterial photosynthetic RCs have been characterized in more detail, both structurally and functionally, than have other transmembrane protein complexes [1-52]. 

S. Klamt, S. Schuster, and E. D. Gilles, Calculability analysis in underdetermined metabolic networks illustrated by a model of the central metabolism in purple nonsulfur bacteria. Biotechnol. Bioeng. 77(7), 734 751 (2002). 

Anoxygenic photosynthetic bacteria. Green sulfur bacteria. Chlorobium, Prosthecochloris purple nonsulfur bacteria Rhodopseudomonas, Rhodospirillum purple sulfur bacteria Chromatium, Thiospirillum... 

Green sulfur and nonsulfur bacteria. In these organisms chlorophylls are present in rodlike particles... 

Photoheterotroph Sunlight Oxidation of organic compounds Organic compounds Nonsulfur purple bacteria... 

Fig. 3 Schematic model of light-harvesting compartments in photosynthetic organisms and their position with respect to the membrane and the reaction centers. RC1(2) Photosystem I(II) reaction centre. Peripheral membrane antennas Chlorosome/FMO in green sulfur and nonsulfur bacteria, phycobilisome (PBS) in cyanobacteria and rhodophytes and peridinin-chlorophyll proteins (PCP) in dyno-phytes. Integral membrane accessory antennas LH2 in purple bacteria, LHC family in all eukaryotes. Integral membrane core antennas B808-867 complex in green nonsulfur bacteria, LH1 in purple bacteria, CP43/CP47 (not shown) in cyanobacteria and all eukaryotes.

The Fenna-Matthews-Olson (FMO) protein is an unusual, water-soluble chlorophyll protein found only in green sulfur bacteria. [18] It is believed to be located between the chlorosome and the cytoplasmatic membrane and functions as an excitation transfer link between the chlorosome and the reaction center. Each subunit contains 7 BChl a molecules embedded in a primarily /3 sheet structured protein. The protein has a trimeric quaternary structure, with a three-fold axis of symmetry in the center of the complex. [55] The green nonsulfur bacteria do not contain the FMO protein. In these organisms the chlorosome transfers energy directly to the integral membrane core antenna B808-865, and then to the reaction center. 

Woodbury, N. W., and Allen, J. P., 1995, The pathway, kinetics and thermodynamics of electron transfer in wild type and mutant hacterial reaction centers of purple nonsulfur hacteria. In Anoxygenic Photosynthetic Bacteria, (R. E. Blankenship, M. T. Madigan, and C. E. Bauer, eds.) pp. 5279557, Kluwer Academic Publishers, Dordrecht, The Netherlands. 

NapB. NapB is a subunit of the heterodimeric periplasmic nitrate reductase (NapAB) and transfers electrons to the catalytic NapA molybdoprotein. Nap systems are found in a number of bacteria, iucluding enterobacteria, aerobic denitrifiers, and nonsulfur purple photo synthetic bacteria. Their physiological function is different in these groups of bacteria and includes redox balancing using nitrate as an electron sink to dispose of excess rednctant, aerobic denitrification, and nitrate scavenging in nitrate-limited environments. 

CO2 fixation is also found in many bacteria, both photosynthetic and non-photosynthetic. The purple sulfur and purple nonsulfur bacteria employ the RPP cycle as do plants. The photosynthetic green bacteria, however, use a group of ferre-doxin-linked carboxylases in a pathway known as the reductive carboxylic acid cycle [ ] ... 

Many phototrophs do not produce O2 as a waste product. Such anoxygenic phototrophs are comprised of purple sulfur, purple nonsulfur, green sulfur, and green nonsulfur bacteria. Although purple sulfur bacteria are typically found in anoxic zones of lakes and sediments, many are capable of photosynthesis under oxic conditions (Van Gemer-den, 1993). Most fix N2 and store S° intra- or extracellularly, and some are capable of chemo-lithoautotrophic growth. Extreme halophilic, sulfi-dic, and mildly thermophilic environments harbor... 

Sinha S. N. and Baneijee R. D. (1997) Ecological role of thiosulfate and sulfide utilizing purple nonsulfur bacteria of a riverine ecosystem. FEMSMicrobiol. Ecol. 24(3), 211-220. 

The membrane-bound PPase does not only hydrolyze PPj for the maintenance of a pool of high energy, it can also form PPj at the expense of the energy liberated in the electron transport chain [13,14]. This enzyme has been found in both purple nonsulfur [13-17] and sulfur photosynthetic bacteria [18], and in mitochondria of lower [19] and higher [20] heterotrophic organisms, and also in chloroplasts from algae and higher plants [21]. 

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