Methyl methanesulfonate (MMS), also known as methyl mesylate, is an

alkylating agent Alkylation is the transfer of an alkyl group from one molecule to another. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting al ...

and a

carcinogen A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive substan ...

. It is also a suspected reproductive toxicant, and may also be a skin/sense organ toxicant. It is used in cancer treatment.Medical.Webends.com: Methyl Methanesulfonate
Medical.webends.com Accessed 14 Feb 08

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 Homologous recombination is a type of genetic recombination in which genetic information is exchanged between two similar or identical molecules of double-stranded or single-stranded nucleic acids (usually DNA as in cellular organisms but may ...

-deficient cells are particularly vulnerable to the effects of MMS. However, it is now believed that MMS stalls

replication fork In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all living organisms acting as the most essential part for biological inheritanc ...

s, and cells that are homologous recombination-deficient have difficulty repairing the damaged replication forks.

References

{{reflist Methyl esters Methylating agents Mesylate esters Reagents for organic chemistry IARC Group 2A carcinogens

Chemical reactions with DNA

See also

References