Enzyme synthesized by Chinese caterpillar fungus hirsutella sinensis to metabolize guanine nucleotide and genes and application of enzyme

The invention relates to IMP (inosine monophosphate) dehydrogenase synthesized by 'Bailing' producing fungus Chinese caterpillar fungus hirsutella sinensis to metabolize guanine nucleotide based on xanthosine monophosphate and coding genes and application of the IMP dehydrogenase. The IMP dehydrogenase comprises proteins shown by SEQ ID No.1, SEQ ID No.2 and SEQ ID No.3, and coding genes of the IMP dehydrogenase correspond to nucleotide sequences shown by SEQ ID No.4, SEQ ID No.5 and SEQ ID No.6. Detailed studies on metabolic pathways of the xanthosine monophosphate synthesizing the guanine nucleotide in principle are carried out and include that cloned DNAs (deoxyribonucleic acids) in the provided nucleotide sequences can be transferred into engineering bacteria by means of transduction, transformation and transconjunction, and high expressivity is given to the host guanine nucleotide by adjusting expressions of guanine nucleotide biosynthetic genes, so that an effective way for increasing output of the guanine nucleotide is provided, and the IMP dehydrogenase and the coding genes have significant application prospects.