Methyl methanesulfonate (MMS), also known as methyl mesylate, is an alkylating agent and a carcinogen. It is also a suspected reproductive toxicant, and may also be a skin/sense organ toxicant.Scorecard Pollution Information Site: Methyl Methanesulfonate Scorecard.org Accessed 14 Feb 08 It is used in cancer treatment.Medical.Webends.com: Methyl Methanesulfonate Medical.webends.com Accessed 14 Feb 08 Its chemical formula is . It is a colorless liquid.
Chemical reactions with DNA MMS methylates DNA predominantly on N7-deoxyguanosine and N3-deoxyadenosine, and to a much lesser extent also methylates at other oxygen and nitrogen atoms in DNA bases, and also methylates one of the non-carbon bound oxygen atoms of the phosphodiester linkage. Originally, this action was believed to directly cause double-stranded DNA breaks, because homologous recombination-deficient cells are particularly vulnerable to the effects of MMS. However, it is now believed that MMS stalls replication forks, and cells that are homologous recombination-deficient have difficulty repairing the damaged replication forks.
See also
Dimethyl sulfite, a chemical with the same molecular formula but different arrangement
References