Search results
Results from the WOW.Com Content Network
Iron sulfides occur widely in nature in the form of iron–sulfur proteins. As organic matter decays under low-oxygen (or hypoxic) conditions such as in swamps or dead zones of lakes and oceans, sulfate-reducing bacteria reduce various sulfates present in the water, producing hydrogen sulfide. Some of the hydrogen sulfide will react with metal ...
The abiotic processes include the rusting of iron-bearing metals, where Fe 2+ is abiotically oxidized to Fe 3+ in the presence of oxygen, and the reduction of Fe 3+ to Fe 2+ by iron-sulfide minerals. The biological cycling of Fe 2+ is done by iron oxidizing and reducing microbes. [14] [15] Iron is an essential micronutrient for almost every ...
The important sulfur cycle is a biogeochemical cycle in which the sulfur moves between rocks, waterways and living systems. It is important in geology as it affects many minerals and in life because sulfur is an essential element (), being a constituent of many proteins and cofactors, and sulfur compounds can be used as oxidants or reductants in microbial respiration. [1]
The iron sulfur proteins contain iron–sulfur clusters, some with elaborate structures, that feature iron and sulfide centers. One broad biosynthetic task is producing sulfide (S 2-), which requires various families of enzymes. Another broad task is affixing the sulfide to iron, which is achieved on scaffolds, which are nonfunctional.
Iron–sulfur clusters are molecular ensembles of iron and sulfide. They are most often discussed in the context of the biological role for iron–sulfur proteins , which are pervasive. [ 2 ] Many Fe–S clusters are known in the area of organometallic chemistry and as precursors to synthetic analogues of the biological clusters.
Iron sulfide or Iron sulphide can refer to range of chemical compounds composed of iron and sulfur. Minerals. By increasing order of stability: Iron(II) sulfide, FeS;
Absorption of dietary iron in iron salt form (as in most supplements) varies somewhat according to the body's need for iron, and is usually between 10% and 20% of iron intake. Absorption of iron from animal products, and some plant products, is in the form of heme iron, and is more efficient, allowing absorption of from 15% to 35% of intake.
Treatment of sulfur with hydrogen gives hydrogen sulfide.When dissolved in water, hydrogen sulfide is mildly acidic: [5] H 2 S ⇌ HS − + H +. Hydrogen sulfide gas and the hydrosulfide anion are extremely toxic to mammals, due to their inhibition of the oxygen-carrying capacity of hemoglobin and certain cytochromes in a manner analogous to cyanide and azide.