Occurrence and function
Vanadium bromoperoxidases have been found in bacteria, fungi, marine macro algae ( seaweeds), and marine microalgae ( diatoms) which produce brominated organic compounds. It has not been definitively identified as the bromoperoxidase of higher eukaryotes, such as murex snails, which have a very stable and specific bromoperoxidase, but perhaps not a vanadium dependent one. While the purpose of the bromoperoxidase is still unknown, the leading theories include that it’s a way of regulating hydrogen peroxide produced by photosynthesis and/or as a self-defense mechanism by producing hypobromous acid which prevents the growth of bacteria. The enzymes catalyse the oxidation of bromide (0.0067% of sea water) by hydrogen peroxide. The resulting electrophilic bromonium cation (Br+) attacks hydrocarbons (symbolized as R-H in the following equation): :R-H + Br− + H2O2 → R-Br + H2O + OH− The bromination acts on a variety of dissolved organic matter and increasingly bromination leads to the formation of bromoform. The vanadium bromoperoxidases produce an estimated 1–2 million tons of bromoform and 56,000 tons of bromomethane annually. Partially in the polar regions, which has high blooms of microalgae in the spring, these compounds have the potential to enter the troposphere and lower stratosphere. Through photolysis, brominated methanes produce a bromine radical (Br.) that can lead to ozone depletion. Most of the earth's natural organobromine compounds arise by the action of this enzyme.References
External links
* * Example structure: * Family/Domain classifications: ** ** ** ** EC 1.11.1 {{Enzyme-stub