While the diatoxanthin (Dt) content of whole cells was enhanced under HL, no decrease was observed under lowered iron supply, ruling out the possibility that the

decreased amounts in FCPa were due to a hampered diadinoxanthin de-epoxidase activity under these conditions. Thus, diatoxanthin not bound to FCPa has to be responsible for protection under the slight reduction in iron supply used here. “
“The applicability of six fluorescent probes (four esterase probes: acetoxymethyl ester of Calcein [Calcein-AM], 5-chloromethylfluorescein diacetate [CMFDA], fluorescein diacetate [FDA], and 2′,7′-dichlorofluorescein diacetate [H2DCFDA]; and two membrane probes: bis-(1,3-dibutylbarbituric acid) trimethine oxonol [DiBAC4(3)] and SYTOX-Green) as vitality stains was tested on live and killed cells of 40 phytoplankton strains in exponential and stationary Smoothened Agonist supplier growth phases, belonging to 12 classes and consisting selleck compound of four cold-water, 26 temperate, and four warm-water species. The combined live/dead ratios of all six probes indicated significant differences between the 12 plankton classes (P < 0.01) and between individual

species (P < 0.05). No specific differences were observed among strains of one species, among species or strains from different origin, nor between cells in exponential and stationary growth phase except for FDA. FDA showed a significant (P < 0.05) drop of <20% in fluorescence intensity in stationary cells. Of the four esterase probes, the live/dead ratios of FDA and CMFDA were not significantly different from each other, and both performed better than Calcein-AM and H2DCFDA (P < 0.001). Of the two membrane probes, DIBAC4(3) stained rhodophytes and euglenophytes much better than 上海皓元医药股份有限公司 SYTOX-Green. The 13 algal strains best stainable (high live/dead ratios) among all six probes belonged to nine genera from six classes of phytoplankton. In conclusion, FDA, CMFDA, DIBAC4(3), and SYTOX-Green represent a wide choice

of vitality probes in the study of phytoplankton ecology, applicable in many species from different algal classes, originating from different regions and at different stages of growth. “
“Common methods for assaying acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymatic activity rely upon radiolabeled substrates or product assay. We developed a novel assay that directly quantifies endogenous DGAT activity through the use of a fluorescently labeled substrate. We performed this assay with microsomal protein, 2-(6-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoyl-1-hexadecanoyl-sn-glycero-3-diacylglycerol (NBD-DAG), and oleoyl-CoA substrates. DGAT activity was analyzed in three species of algae as well as rat liver. The protocol proved to be sensitive and reliable. This assay may be used to facilitate research in the areas of biodiesel, oilseed crops, and triacylglycerol-related human pathologies.