| abstract |
It is intended to provide an industrially advantageous method of producing 2,6-dihydroxybenzoic acid which comprises contacting an optionally processed microorganism with resorcin in an aqueous medium containing carbonate ion and/or carbon dioxide. A highly thermotolerant enzyme capable of producing 2,6-dihydroxybenzoic acid from resorcin is found out in a microorganism belonging to the genus Rhizobium. A transformant microorganism having been transformed by a gene encoding this enzyme is obtained. 2,6-Dihydroxybenzoic acid is produced by treating resorcin with the above-described enzyme produced by the above-described transformant microorganism in an aqueous medium in the presence of carbonate ion and/or carbon dioxide. In producing 2,6-dihydroxybenzoic acid from resorcin by using an optionally processed microorganism in an aqueous medium containing carbonate ion and/or carbon dioxide, the accumulation level is elevated by adding an organic solvent to an aqueous solvent, regulating the oxidation of resorcin, or sequentially adding resorcin or the optionally processed microorganism. In this method, more improved results can be obtained by using the transformant microorganism as described above. This production method is applicable to the production of 2,3-dihydroxybenzoic acid with the use of catechol. |