Manganese is also used in portland cement mixtures. Manganese is an important element for human health, essential for development, metabolism, and the antioxidant system. Nevertheless, excessive exposure or intake may lead to a condition known as manganism, a neurodegenerative disorder that causes dopaminergic neuronal death and symptoms similar to Parkinson's disease. The classes of enzymes that have manganese cofactors is large and includes oxidoreductases, transferases, hydrolases, lyases, isomerases, ligases, lectins, and integrins. The reverse transcriptases of many retroviruses (though not lentiviruses such as HIV) contain manganese. The best-known manganese-containing polypeptides may be arginase, the diphtheria toxin, and Mn-containing superoxide dismutase (Mn-SOD).
Manganese Mines Mines Wildlife Management Area, a conservation area. The main industry is now farming. The name of this community derives from the discovery and mining of manganese here, beginning in the 1880s and ending in the 1890s. Also, Lafarge Canada operated a limestone quarry at Manganese Mines which closed in 1996. The limestone was used to produce cement. Manganese Mines Manganese Mines is an unincorporated community in Colchester County, Nova Scotia, Canada. This community is located about six miles north-east of Truro, between the South Branch North River and the Salmon River. The land was previously part of Onslow Township. It