<p>A DNA having a 5'-inosinate dehydrogenase gene and further having a Hind III cleavage site 2.9 kilo base pairs can be produced from the chromosomal DNA of a guanosine and/or xanthosine-producing strain of the genus Bacillus. A vector with the DNA obtained above is used to transform Bacillus strain capable of producing guanosine, and the transformed Bacillus strain is useful to increase the guanosine productivity as compared with the case in which a strain before transformantion is used.</p>
