Abstract: The present invention relates to a method for modulating thermostability or acid tolerance of a microbe by mutating a nucleic acid molecule encoding a homoserine o-succinyltransferase (MetA) to obtain a nucleic acid molecule encoding a mutant MetA and transforming a microbial cell with the nucleic acid molecule encoding a mutant MetA. The microbe, a bacteria expressing the mutant MetA of the present invention represents a growth rate improved in a vigorous environment such as higher-temperatures and/or lower pH conditions.

Abstract: The present invention relates a method for modulating thermostability or acid tolerance of a microbe, comprising the steps of: (a) conferring a substitution mutation to a homoserine o-succinyltransferase (MetA)-encoding nucleotide sequence; and (b) transforming the MetA-encoding nucleotide sequence into a microbial cell. The mutated MetA of the present invention shows stability notably enhanced at high-temperatures and/or under acid conditions or decreased at mild temperature, and the microbe, particular bacteria expressing the mutated MetA of the present invention represents a growth rate improved in a vigorous environment such as higher-temperatures and/or lower acid conditions.