To elucidate a protein enhancing acetic acid resistance at a gene level; to obtain a microorganism having high acetic acid resistance and capable of efficiently producing acetic acid in high concentration; and to provide a method for efficiently producing vinegar containing the acetic acid in a high concentration by using the microorganisms.

The protein OMP1, the DNA of the gene encoding the protein OMP1, and the microorganism having the high acetic acid resistance and obtained by amplifying the number of copies of the DNAs in the cells of the microorganism are provided. The method for producing the vinegar comprises culturing the microorganisms having alcohol-oxidizing performance in the microorganisms in a medium containing alcohol to form and accumulate the acetic acid in the medium.