The absorption of Cl(-) and water from ingested seawater in the marine fish intestine is accomplished partly through Cl(-)/HCO(3)(-) exchange. Recently, a H(+) pump (vacuolar-type H(+)-ATPase) was found to secrete acid into the intestinal lumen, and it may serve to titrate luminal HCO(3)(-) and facilitate further Cl(-)/HCO(3)(-) exchange, especially in the posterior intestine, where adverse con...

Selenium (Se) is an essential micronutrient that can cause embryotoxicty at levels 7-30 times above essential concentrations. Exposure to hypersaline conditions and 50 μM selenomethionine (SeMet) decreased embryo hatch and depleted glutathione in Japanese medaka embryos without affecting Se accumulation. To better understand the impacts of nonchemical stressors on developmental toxicity of Se i...

Methanogenic archaea accumulate glycine betaine in response to hypersalinity, but the regulation of proteins involved, their mechanism of activation and regulation of the corresponding genes are largely unknown. Methanosarcina mazei differs from most other methanoarchaea in having two gene clusters both encoding a potential glycine betaine transporter, Ota and Otb. Western blot as well as quant...

Ferritins store and sequester iron, and regulate iron homeostasis. The cDNA for a stress-responsive phytoferritin, previously identified in the extracellular matrix (ECM) of chickpea (Cicer arietinum), was cloned and designated CaFer1. The CaFer1 transcript was strongly induced in chickpea exposed to dehydration, hypersalinity and ABA treatment. Additionally, it has role in the defense against ...

Choline dehydrogenase catalyzes the oxidation of choline to glycine betaine via betaine aldehyde as intermediate. Biotechnological applications of glycine betaine in transgenic plant improvement have been shown to have enhanced tolerance towards hypersalinity and freezing. It can also restore and maintain osmotic balance of living cells under stress. In this study, choline dehydrogenase (betA) ...

Mangrove forests provide essential ecosystem services, but are threatened by habitat loss, effects of climatic change and chemical pollutants. Hypersalinity can also lead to mangrove mortality, although mangroves adapted saline habitats. A recent dieback event >9 ha temperate ( Avicennia marina ) in South Australia allowed evaluate the generality anthropogenic impacts on ecosystems. We c...

In Haloferax volcanii, AglD adds the final hexose to the N-linked pentasaccharide decorating the S-layer glycoprotein. Not knowing the natural substrate of the glycosyltransferase, together with the challenge of designing assays compatible with hypersalinity, has frustrated efforts at biochemical characterization of AglD activity. To circumvent these obstacles, an in vivo assay designed to iden...

The effect of severe drought on the functional groups that sustain base mangrove food webs in semi-arid areas is largely unknown. We therefore analyzed intra-annual variation assemblages and copepods a shallow, low-inflow estuary Brazilian coast when most ever occurred. lowest density was found April (upstream region) highest August (downstream region). Three main were identified, sorted by spa...