The mthA mutation conferring low-level resistance to streptomycin enhances antibiotic production in Bacillus subtilis by increasing the S-adenosylmethionine pool size.

ABSTRACT: Certain Str(r) mutations that confer low-level streptomycin resistance result in the overproduction of antibiotics by Bacillus subtilis. Using comparative genome-sequencing analysis, we successfully identified this novel mutation in B. subtilis as being located in the mthA gene, which encodes S-adenosylhomocysteine/methylthioadenosine nucleosidase, an enzyme involved in the S-adenosylmethionine (SAM)-recycling pathways. Transformation experiments showed that this mthA mutation was responsible for the acquisition of low-level streptomycin resistance and overproduction of bacilysin. The mthA mutant had an elevated level of intracellular SAM, apparently acquired by arresting SAM-recycling pathways. This increase in the SAM level was directly responsible for bacilysin overproduction, as confir

SUBMITTER: Tojo S 

PROVIDER: S-EPMC3993368 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature