[Construction and Characterization of B850-Only LH2 Energy Transfer System in Purple Bacteria].

To seek microscopic molecular mechanism of energy transfer and complex reconstitution in the photosynthesis, the conditions for construction of B850-only peripheral light-harvesting complex (LH2) and their properties were investigated using absorption, fluorescence spectroscopy, molecular sieve chromatography, ultrafiltration and sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) from the purple bacteria. The results indicated that bacteriochlorophylls (BChl) of B800 incubated in 10 mmo · L(-1) Tris-HCl (pH 8.0) buffer are selectively released from their binding sites of LH2 of Rhodobacter azotoformans (A-LH2) by 0.

[Influence of LDAO on the conformation and release of bacteriochlorophyll of peripheral light-harvesting complex (LH2) from Rhodobacter azotoformans].

The aim of this study is to reveal the interaction relationships between lauryl dimethylamine N-oxide (LDAO) and peripheral light-harvesting complex (LH2) as well as the influence of LDAO on structure and function of LH2. In the present work, the effects of LDAO on the conformation and release processes of bacteriochlorophyll (BChl) of LH2 when incubated under different temperature and pH in the presence and absence of LDAO were investigated by spectroscopy. The results indicated that (1) the presence of LDAO resulted in alterations in the conformation, alpha-helix content, and spectra of Tyr and B850 band of LH2 at room temperature and pH 8.

Mameliella alba gen. nov., sp. nov., a marine bacterium of the Roseobacter clade in the order Rhodobacterales.

A Gram-negative, non-motile, rod-shaped bacterial strain, JLT354-W(T), that accumulates poly-beta-hydroxybutyrate granules was isolated from the South China Sea. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strain was related to members of the genera Antarctobacter, Sagittula, Oceanicola and Loktanella; levels of similarity between strain JLT354-W(T) and members of the above genera were less than 92.0 %.

Biogeography and phylogeny of the NOR5/OM60 clade of Gammaproteobacteria.

The phylogeny, abundance, and biogeography of the NOR5/OM60 clade was investigated. This clade includes "Congregibacter litoralis" strain KT71, the first cultured representative of marine aerobic anoxygenic phototrophic Gammaproteobacteria. More than 500 16S rRNA sequences affiliated with this clade were retrieved from public databases.

Yangia pacifica gen. nov., sp. nov., a novel member of the Roseobacter clade from coastal sediment of the East China Sea.

An aerobic, Gram-negative bacterial isolate, strain DX5-10T, was isolated from coastal sediment of the East China Sea. The taxonomy of strain DX5-10T was studied by phenotypic and phylogenetic methods. Strain DX5-10T was motile, formed faint-yellowish colonies and was positive for catalase reaction and weakly positive for oxidase reaction.

[Bacterial conversion of sulfur-and phosphorous-compounds and microbial diversity in sediments from a near-shore marine-cultural region].

The H2S-producing bacteria and the phosphorous-cycling bacteria in sediments from near-shore marine-cultural region were investigated. Results indicate that the bacterial H2S production in aerobic condition is the dominating process to produce H2S in the sediment of cultural pond. The total counts of H2S-producing bacteria utilizing cysteine and Na2S2O3 were 1.

Evolution of nutrient structure and phytoplankton composition in the Jiaozhou Bay ecosystem.

The inventories of nutrients in the surface water and large phytoplankton( > 69 microm) were analyzed from the data set of JERS ecological database about a typical coastal waters, the Jiaozhou Bay, China, from 1960s for N, P and from 1980s for Si. By examining long-term changes of nutrient concentration, calculating stoichiometric balance, and comparing diatom composition, Si limitation of diatom production was found to be more possible. The possibility of Si limitation was from 37% in 1980s to 50% in 1990s.