Alcaligenes faecalis, resistant to the toxic effects of 0.01 M sodium arsenite, was isolated from raw sewage and shown to be capable of oxidizing arsenite to arsenate. When the organisms were grown in chemically defined medium, this conversion was due to the appearance at stationary phase of an intracellular, oxygen-sensitive, inducible enzyme and/or component of the electron transport system; ...

Development of methods for quantification of cellular association and patterns in growing bacterial colony is of considerable current interest, not only to help understand multicellular behavior of a bacterial species but also to facilitate detection and identification of a bacterial species in a given space and under a given set of condition(s). We have explored quantitative spectral light sca...

Background & Aims: Sodium arsenite, an environmental pollutant, produces free radicals with harmful effects on the reproductive system. The aim of this study was to investigate the effect of curcumin, as a strong antioxidant, on the testis tissue and spermatogenic cell population in mice treated with sodium arsenite. Methods: In this experimental study, A...

The Bacillus subtilis skin element confers resistance to arsenate and arsenite. The ars operon in the skin element contains four genes in the order arsR, ORF2, arsB, and arsC. Three of these genes are homologous to the arsR, arsB, and arsC genes from the staphylococcal plasmid pI258, while no homologs of ORF2 have been found. Inactivation of arsR, arsB, or arsC results in either constitutive ex...

materials and methods in the present study, a potent nk-producing strain was isolated from cow milk and identified. to enhance the yield of nk, effect of various parameters such as ph, temperature, carbon source, nitrogen source and inoculum size were optimized. strain improvement of p. aeruginosa cmss was done by random uv-mutagenesis. nattokinase was partially purified and the activity was de...

in april, 2013, a suzhou hospital reported a nitrite intoxication patient in coma as well as 2 family members with the similar symptom 5 days ahead. we investigated the event to identify the cause, source and possible pollution ways of the contamination.we defined case as any person living in yshy community who has cyanosis and with at least one of the following symptoms: dizziness, headache, f...

Plasmid R773, which codes for resistances to arsenate, arsenite, and antimony, was introduced into Escherichia coli strain AN120, a mutant deficient in the H+-translocating ATPase of oxidative phosphorylation. Cultures depleted of endogenous energy reserves were loaded with 74AsO3-4, and arsenate efflux was measured after dilution into medium containing various energy sources and inhibitors. Ra...

Ochreous precipitates containing 5.5-69.8 g/kg As were isolated from mine drainage in Finland and were composed of schwertmannite, ferrihydrite, and goethite. Schwertmannite formation was favored at pH 3-4, but its structure was degraded at high As levels. A series of coprecipitates were therefore prepared from mixed iron arsenate/sulfate solutions to define the limits of schwertmannite stabili...