Bacteria, purple

Breton J, Martin J-L, Fleming G R and Lambry J-C 1988 Low-temperature femtosecond spectroscopy of the initial step of electron transfer in reaction centers from photosynthetic purple bacteria Biochemistry 27 8276... 

Pullerits T, Visscher K J, Hess S, Sundstrom V, Freiberg A, Timpmann K and Van Grondelle R 1994 Energy-transfer in the inhomogeneously broadened core antenna of purple bacteria-a simultaneous fit of low-intensity picosecond absorption and fluorescence kinetics Biophys. J. 66 236-48... 

The light-harvesting complex LHl is directly associated with the reaction center in purple bacteria and is therefore referred to as the core or inner antenna, whereas LH2 is known as the peripheral antenna. Both are huilt up from hydrophohic a and p polypeptides of similar size and with low hut significant sequence similarity. The two histidines that hind to chlorophyll with absorption maxima at 850 nm in the periplasmic ring of LH2 are also present in LHl, but the sequence involved in binding the third chlorophyll in LH2 is quite different in LHl. Not surprisingly, the chlorophyll molecules of the periplasmic ring are present in LHl but the chlorophyll molecules with the 800 nm absorption maximum are absent. 

Michel, H., Deisenhofer, J. Relevance of the photosynthetic reaction center from purple bacteria to the structure of photosystem II. BicKhemistry 27 1-7, 1988. 

Anoxygenic photosynthesis Type of photosynthesis in green and purple bacteria in which oxygen is not produced. 

In contrast to common usage, the distinction between photosynthetic and respiratory Rieske proteins does not seem to make sense. The mitochondrial Rieske protein is closely related to that of photosynthetic purple bacteria, which represent the endosymbiotic ancestors of mitochondria (for a review, see also (99)). Moreover, during its evolution Rieske s protein appears to have existed prior to photosynthesis (100, 101), and the photosynthetic chain was probably built around a preexisting cytochrome be complex (99). The evolution of Rieske proteins from photosynthetic electron transport chains is therefore intricately intertwined with that of respiration, and a discussion of the photosynthetic representatives necessarily has to include excursions into nonphotosynthetic systems. 

The characteristic derivative-shaped feature at g 1.94 first observed in mitochondrial membranes has long been considered as the sole EPR fingerprint of iron-sulfur centers. The EPR spectrum exhibited by [4Fe-4S] centers generally reflects a ground state with S = I and is characterized by g values and a spectral shape similar to those displayed by [2Fe-2S] centers (Fig. 6c). Proteins containing [4Fe-4S] centers, which are sometimes called HIPIP, essentially act as electron carriers in the photoinduced cyclic electron transfer of purple bacteria (106), although they have also been discovered in nonphotosynthetic bacteria (107). Their EPR spectrum exhibits an axial shape that varies little from one protein to another with g// 2.11-2.14 and gi 2.03-2.04 (106-108), plus extra features indicative of some heterogeneous characteristics (Pig. 6d). 

Bacteriochlorophyll a 365, 772 Purple bacteria Grey-pink -C0CH3 -CH3 -CHjCH3 -CH CHjCOO-phytyl Single Single... 

Ehrenreich A, F Widdel (1994) Anaerobic oxidation of ferrous iron by purple bacteria, a new type of photo-trophic metabolism. Appl Environ Microbiol 60 4517-4526. 

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. 

In purple bacteria investigated thus far, the development of the photosynthetic apparatus which is controlled by the oxygen partial pressure is not influenced by light. However, the prevalent light intensity modifies the morphogenetic process of formation of intracytoplasmic membranes. Light intensity also controls the total bacteriochlorophyll concentration per cell and per membrane protein, as well as regulating... 

Clayton, R.K. Phototaxis of purple bacteria. In Encyclopedia of Plant Physiology (Ruh-land, W., ed.). Vol. 17/1. Berlin, Gottingen, Heidelberg Springer 1959, pp. 371-387... 

Man ten, A. Phototaxis, phototropism and photosynthesis in purple bacteria and blue-green algae. Thesis, Utrecht, 1948... 

E. Hustede, A. Steinbuchel, H. G Schlegel (1993) Relationship between the photoproduction of hydrogen and the accumulation of PHB in non-sulphur purple bacteria, Appl. microbiol. Biotechnol., 39 87-93... 

Table 1. Maximum hydrogen photoproduction by batch cultures or resting cells of purple bacteria...

Comparing with resting cells, batch and continuous cultures, the immobilized systems showed decreased rates of hydrogen photoproduction per unit of surface. As a result the efficiency of hydrogen photoproduction by these systems were also lower than highest reported for resting cells [Miyake, Kawamura, 1987], It suggests that cultures had not optimal conditions in some respect. So, here is a room for fiirther improvement of systems with immobilized purple bacteria. 

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