Background Sulfur-deprived cultivation of Chlamydomonas reinhardtii, referred as "two-stage culture" transferring the cells from regular algal medium to sulfur-deplete one, has been extensively studied to improve photobio-H2 production in this green microalga. During sulfur-deprivation treatment, the synthesis of a key component of photosystem II complex, D1 protein, was inhibited and improved ...

Gradients of oxygen and sulfide measured towards individual cells of the large nitrate-storing sulfur bacterium Thiomargarita namibiensis showed that in addition to nitrate oxygen is used for oxidation of sulfide. Stable gradients around the cells were found only if acetate was added to the medium at low concentrations.

ultrastructural changes in immature articular carilage were studied after treatment of 5-weeks-old rats with ofloxacin, a fluoroquinolone, and in magnesium deficiency.we concluded that quinolone-induced arthropathy is probably due to chelation of functionally available magnesium in joint cartilage as magnesium deficiency in joint cartilage could impair chondrocyte-matrix- interaction which is m...

Previous studies have demonstrated that a, semisynthetic diet containing 12 per cent casein is deficient in sulfur amino acids for the growth of tissues in rats (1), supplementation with 0.7 per cent DL-methionine increasing the growth opti mally. A transplanted sarcoma was found to de velop most rapidly in rats fed this sulfur amino acid-deficient diet. Supplementing with 0.7 per cent methioni...

Under sulfur deprivation conditions, the green alga Chlamydomonas reinhardtii produces hydrogen in the light in a sustainable manner thanks to the contribution of two pathways, direct and indirect. In the direct pathway, photosystem II (PSII) supplies electrons to hydrogenase through the photosynthetic electron transport chain, while in the indirect pathway, hydrogen is produced in the absence ...

The cloned oprH gene of Pseudomonas aeruginosa was mutated by inserting a 1.4-kbp fragment that encodes tetracycline resistance. This mutated gene was then incorporated into the P. aeruginosa chromosome by homologous recombination. Growth of the resultant oprH::tet mutant in Mg(2+)-deficient medium had little effect on susceptibility to polymyxin B, gentamicin, or EDTA unless the mutant was com...

Previous communications from this laboratory have established the function of pyridoxine derivatives' in the tyrosine decarboxylase system of Streptococcus faecalis, and a synthetic medium has been described for the production of cells active in this function (Bellamy and Gunsalus, 1943, 1944). Cells grown in media deficient in,pyridoxine derivatives have been shown to contain the tyrosine deca...

Weak decay rates under stellar density and temperature conditions holding at the rapid proton-capture process are studied in neutron-deficient medium-mass waiting-point nuclei extending from Ni up to Sn. Neighboring isotopes to these waiting-point nuclei are also included in the analysis. The nuclear structure part of the problem is described within a deformed Skyrme Hartree-Fock + BCS + quasip...

The alphaproteobacterium "Candidatus Pelagibacter ubique" strain HTCC1062 and most other members of the SAR11 clade lack genes for assimilatory sulfate reduction, making them dependent on organosulfur compounds that occur naturally in seawater. To investigate how these cells adapt to sulfur limitation, batch cultures were grown in defined medium containing either limiting or nonlimiting amounts...

As a promising material for heterogeneous catalytic applications, layered iron (II) monosulfide (FeS) contains active edges and an inert basal (001) plane. Activating the plane could improve performance of FeS towards CO2 activation reduction reactions. Herein, we report dispersion-corrected density functional theory (DFT-D3) calculations adsorption elementary steps involved in its through reve...