What is respiratory arsenate reductase?

The arsenite oxidase is a resistance mechanism converting highly toxic high arsenite levels to relatively less toxic arsenate, while respiratory arsenate reductase functions as a terminal electron acceptor, allowing anaerobic growth in the absence of oxygen.

What is arsenate respiration?

Often, arsenic is released into water by microbes that breathe, or respire, arsenic-containing compounds. Caltech researchers have now determined the structure of the bacterial enzyme that enables arsenic respiration.

What is arsenic used for?

Industrial processes. Arsenic is used industrially as an alloying agent, as well as in the processing of glass, pigments, textiles, paper, metal adhesives, wood preservatives and ammunition. Arsenic is also used in the hide tanning process and, to a limited extent, in pesticides, feed additives and pharmaceuticals.

What is arsenite and arsenic?

In chemistry, an arsenite is a chemical compound containing an arsenic oxoanion where arsenic has oxidation state +3. Note that in fields that commonly deal with groundwater chemistry, arsenite is used generically to identify soluble AsIII anions.

What is the difference between arsenite and arsenate?

As nouns the difference between arsenate and arsenite is that arsenate is (chemistry) any salt or ester of arsenic acid while arsenite is (chemistry) any oxyanion of trivalent arsenic, especially the aso33- anion (or protonated derivatives); any salt containing this anion, or any ester of arsenious acid.

Which form of arsenic is more toxic?

Arsine gas is the most toxic arsenical (acute exposure). Arsenic is an element and is a naturally occurring mineral found widely in the environment.

Is arsenic toxic?

Exposure to high enough amounts of arsenic can be fatal. Exposure to lower levels of arsenic over longer periods of time can cause skin changes, liver and kidney damage, and a shortage of red and white blood cells, which can lead to fatigue and an increased risk of infections.

How does arsenic affect the citric acid cycle?

Furthermore, trivalent inorganic arsenic inhibits pyruvate dehydrogenase by binding to the sulfydryl groups of dihydrolipoamide, resulting in a reduced conversion of pyruvate to acetyl coenzyme A (CoA), so that both the citric acid cycle activity and production of cellular ATP are decreased [115].

How does arsenic interact with carbonate minerals?

The interaction of geogenic arsenic (As) with carbonate minerals depends on the biological and geochemical conditions of the environment. This study sheds light on how different environmental conditions influence the carbonate mineral formation and the interaction with As.

Does as (III) form strong complexes with (bi) carbonate?

A recent hypothesis that As (III) forms strong complexes with (bi)carbonate is tested by measuring the solubility of As 2 O 3 in concentrated (up to 0.72 m) bicarbonate solutions at near-neutral pH and 25.0 ± 1.8 °C.

Is arsenate in calcite axial or non-axial?

Reeder et al. (1994) and Alexandratos et al. (2007) favored the non-axial model to explain the inclusion of arsenate into calcite given it causes lower distortions than those of the axial position arrangement.

When does arsenate adsorption on monohydrocalcite favor transformation to aragonite?

Fukushi et al. (2011) report that when low concentrations of arsenate (i.e., 7.94 ppm) are adsorbed onto monohydrocalcite (MHC), transformation to aragonite is favored.