Mutagenic and inactivating effects of methyl alkylaminosulfonates on Escherichia coli

Methyl alkylamino methanesulfonates are mutagenic agents as shown by treating several strains of E. coli at pH 7. Methyl methylaminosulfonate (CH3-NH-SO3-CH3) was more efficient than methyl ethylaminosulfonate (C2H5-NH-SO3-CH3) which itself was more efficient than methyl isopropylaminosulfonate (C3H7-NH-SO3-CH3). Methyl methylaminosulfonate seemed to be at least as effective as methyl methanesulfonate (CH3-SO3-CH3). Methyl methylaminosulfonate produced a yield of up to 1% of auxotrophic mutants. All three new mutagens appeared to react according to the same mechanism by ester fission and methylation of nucleophilic groups as is known for methyl methanesulfonate. The reaction mechanism seems to be of the SN2 type.