Effect of chlorpyrifos-exposure on the expression levels of CYP genes in Daphnia magna and examination of a possibility that an up-regulated clan 3 CYP, CYP360A8, reacts with pesticides.

Daphnia magna is a test organism used for ecological risk assessments of pesticides, but little is known about the expression levels of cytochrome P450s (CYP)s and their changes after pesticide exposure in the less than 24-h-olds used for ecotoxicity tests. In this study, D. magna juveniles were exposed to 0.

Kre6 (yeast 1,6-β-transglycosylase) homolog, PhTGS, is essential for β-glucan synthesis in the haptophyte .

Haptophytes synthesize unique β-glucans containing more β-1,6-linkages than β-1,3 linkages, as a storage polysaccharide. To understand the mechanism of the synthesis, we investigated the roles of Kre6 (yeast 1,6-β-transglycosylase) homologs, PhTGS, in the haptophyte . RNAi of repressed β-glucan accumulation and simultaneously induced lipid production, suggesting that PhTGS is involved in β-glucan synthesis and that the knockdown leads to the alteration of the carbon metabolic flow.

Cellular response of to a solid surface culture environment.

Attached culture allows high biomass productivity and is a promising biomass cultivating system because neither a huge facility area nor a large volume of culture medium are needed. This study investigates photosynthetic and transcriptomic behaviors in cells on a solid surface after their transfer from liquid culture to elucidate the physiological and gene-expression regulatory mechanisms that underlie their vigorous proliferation. The chlorophyll content shows a decrease at 12 h after the transfer; however, it has fully recovered at 24 h, suggesting temporary decreases in the amounts of light harvesting complexes.

Utilization of piperonyl butoxide and 1-aminobenzotriazole for metabolic studies of toxic chemicals in Daphnia magna and Chironomus yoshimatsui.

Daphnids and chironomids have been used to assess the ecological effects of chemicals released into water bodies; however, the toxicity mechanisms in organisms are generally difficult to identify. Here, we developed a system capable of estimating the contribution of cytochrome P450 (CYP) to the metabolism of test substances in Daphnia magna and Chironomus yoshimatsui based on toxicity differences in the absence and presence of the CYP inhibitors piperonyl butoxide (PBO) and 1-aminobenzotriazole (ABT). The optimum concentrations of PBO and ABT that could effectively reduce the toxicity of diazinon, which is toxic after oxidative metabolism in vivo, were determined as 0.

One of the isoamylase isoforms, CMI294C, is required for semi-amylopectin synthesis in the rhodophyte .

Most rhodophytes synthesize semi-amylopectin as a storage polysaccharide, whereas some species in the most primitive class (Cyanidiophyceae) make glycogen. To know the roles of isoamylases in semi-amylopectin synthesis, we investigated the effects of gene ( and )-deficiencies on semi-amylopectin molecular structure and starch granule morphology in (Cyanidiophyceae). Semi-amylopectin content in a -disruption mutant () was not significantly different from that in the control strain, while that in a -disruption mutant () was much lower than those in the control strain, suggesting that CMI294C is essential for semi-amylopectin synthesis.

Carbonic anhydrase inhibitor induces otic hair cell apoptosis via an intrinsic pathway and ER stress in zebrafish larvae.

Carbonic anhydrase (CA) catalyzes reversible hydration of CO to HCO to mediate pH and ion homeostasis. Some chemical pollutants have been reported to have inhibitory effects on fish CA. In this study, we investigated effects of a CA inhibitor ethoxyzolamide (EZA) on neuromasts development during zebrafish embryogenesis, since embryogenesis in aquatic organisms can be particularly sensitive to water pollution.

Requirement of the exopolyphosphatase gene for cellular acclimation to phosphorus starvation in a cyanobacterium, Synechocystis sp. PCC 6803.

Polyphosphate, which is ubiquitous in cells in nature, is involved in a myriad of cellular functions, and has been recently focused on its metabolism related with microbial acclimation to phosphorus-source fluctuation. In view of the ecological importance of cyanobacteria as the primary producers, this study investigated the responsibility of polyphosphate metabolism for cellular acclimation to phosphorus starvation in a cyanobacterium, Synechocystis sp. PCC 6803, with the use of a disruptant (Δppx) as to the gene of exopolyphosphatase that is responsible for polyphosphate degradation.

Energy conservation in photosynthetic microorganisms.

Photosynthesis is a biological process of energy conversion from solar radiation to useful organic compounds for the photosynthetic organisms themselves. It, thereby, also plays a role of food production for almost all animals on the Earth. The utilization of photosynthesis as an artificial carbon cycle is also attracting a lot of attention regarding its benefits for human life.

Characterization of the mechanism of thioredoxin-dependent activation of γ-glutamylcyclotransferase, RipAY, from Ralstonia solanacearum.

A class II ChaC protein, RipAY, from phytopathogenic bacterium, Ralstonia solanacearum exhibits γ-glutamylcyclotransferase (GGCT) activity to degrade intracellular glutathione in host cells upon its interaction with host thioredoxins (Trxs). To understand the Trx-dependent activation of RipAY, we constructed various deletion mutants of RipAY and found the determinant region for GGCT activation in the N- and C-terminal sequences of RipAY by analyzing their yeast growth inhibition activity and the interaction with Trxs. Mutational analysis of the active site cysteine residues of Arabidopsis thaliana Trx-h5 (AtTrx-h5), one of the most efficiently stimulating Trxs, revealed that each active site cysteine residue of AtTrx-h5 contributes to efficient RipAY-binding and -activation activity.

Regulatory carbon metabolism underlying seawater-based promotion of triacylglycerol accumulation in Chlorella kessleri.

Chlorella kessleri accumulates triacylglycerol usable for biodiesel-fuel production to >20% dry cell weight in three days when cultured in three-fold diluted seawater, which imposes the combinatory stress of hyperosmosis and nutrients limitation. The quantitative behavior of major C-compounds, and related-gene expression patterns were investigated in Chlorella cells stressed with hyperosmosis, nutrients limitation, or their combination, to elucidate the C-metabolism for economical seawater-based triacylglycerol accumulation. Combinatory-stress cells showed repressed protein synthesis with initially accumulated starch being degraded later, the C-metabolic flow thereby being diverted to fatty acid and subsequent triacylglycerol accumulation.

Involvement of Acidic Polysaccharide Ph-PS-2 and Protein in Initiation of Coccolith Mineralization, as Demonstrated by In Vitro Calcification on the Base Plate.

Coccolithophorids, unicellular marine microalgae, have calcified scales with elaborate structures, called coccoliths, on the cell surface. Coccoliths generally comprise a base plate, CaCO, and a crystal coat consisting of acidic polysaccharides. In this study, the in vitro calcification conditions on the base plate of Pleurochrysis haptonemofera were examined to determine the functions of the base plate and acidic polysaccharides (Ph-PS-1, -2, and -3).

Factors Associated with Neck and Shoulder Pain in Volunteers.

Introduction: The aims of the present study were 1) to examine the association between neck and shoulder pain (NSP) and lifestyle in the general population and 2) to examine if sagittal spino-pelvic malalignment is more prevalent in NSP.

Methods: A total of 107 volunteers (mean age, 64.5 years) were recruited in this study from listings of resident registrations in Kihoku region, Wakayama, Japan.

Carbonic Anhydrase Inhibitors Induce Developmental Toxicity During Zebrafish Embryogenesis, Especially in the Inner Ear.

In vertebrates, carbonic anhydrases (CAs) play important roles in ion transport and pH regulation in many organs, including the eyes, kidneys, central nervous system, and inner ear. In aquatic organisms, the enzyme is inhibited by various chemicals present in the environment, such as heavy metals, pesticides, and pharmaceuticals. In this study, the effects of CA inhibitors, i.

Pleurochrysome: A Web Database of Pleurochrysis Transcripts and Orthologs Among Heterogeneous Algae.

Pleurochrysis is a coccolithophorid genus, which belongs to the Coccolithales in the Haptophyta. The genus has been used extensively for biological research, together with Emiliania in the Isochrysidales, to understand distinctive features between the two coccolithophorid-including orders. However, molecular biological research on Pleurochrysis such as elucidation of the molecular mechanism behind coccolith formation has not made great progress at least in part because of lack of comprehensive gene information.

Profiling of lipid and glycogen accumulations under different growth conditions in the sulfothermophilic red alga Galdieria sulphuraria.

The unicellular red alga Galdieria sulphuraria grows efficiently and produces a large amount of biomass in acidic conditions at high temperatures. It has great potential to produce biofuels and other beneficial compounds without becoming contaminated with other organisms. In G.

Lipid is absorbed in the stomach by epithelial neoplasms (adenomas and early cancers): a novel functional endoscopy technique.

Background And Study Aims: The authors have successfully demonstrated that the white opaque substance (WOS) identified in gastric epithelial neoplasms is an accumulation of minute lipid droplets on the epithelial neoplasm. It is not known whether the lipid droplets originate from externally ingested lipids (typically foods). The purpose of this study was to investigate whether the oral ingestion of foods containing emulsified fats increases the density of the WOS in epithelial neoplasms.