Dataset Information

Overexpression of a cloned IMP dehydrogenase gene of Candida albicans confers resistance to the specific inhibitor mycophenolic acid.

ABSTRACT: An IMP dehydrogenase gene was isolated from Candida albicans on a approximately 2.9-kb XbaI genomic DNA fragment. The putative Candida IMP dehydrogenase gene (IMH3) encodes a protein of 521 amino acids with extensive sequence similarity to the IMP dehydrogenases of Saccharomyces cerevisiae and various other organisms. Like the S. cerevisiae IMH3 sequence characterized in the genome sequencing project, the open reading frame of the C. albicans IMH3 gene is interrupted by a small intron (248 bp) with typical exon-intron boundaries and a consensus S. cerevisiae branchpoint sequence. IMP dehydrogenase mRNAs are detected in both the yeast and hyphal forms of C. albicans as judged by Northern hybridization. Growth of wild-type (sensitive) C. albicans cells is inhibited at 1 microg of mycophenolic acid (MPA), a specific inhibitor of IMP dehydrogenases, per ml, whereas transformants hosting a plasmid with the IMH3 gene are resistant to MPA levels of up to at least 40 microg/ml. The resistance of cells to MPA is gene dosage dependent and suggests that IMH3 can be used as a dominant selection marker in C. albicans.

SUBMITTER: Kohler GA

PROVIDER: S-EPMC178971 | biostudies-other | 1997 Apr

REPOSITORIES: biostudies-other

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Overexpression of a cloned IMP dehydrogenase gene of Candida albicans confers resistance to the specific inhibitor mycophenolic acid.

Köhler G A GA White T C TC Agabian N N

Journal of bacteriology 19970401 7

An IMP dehydrogenase gene was isolated from Candida albicans on a approximately 2.9-kb XbaI genomic DNA fragment. The putative Candida IMP dehydrogenase gene (IMH3) encodes a protein of 521 amino acids with extensive sequence similarity to the IMP dehydrogenases of Saccharomyces cerevisiae and various other organisms. Like the S. cerevisiae IMH3 sequence characterized in the genome sequencing project, the open reading frame of the C. albicans IMH3 gene is interrupted by a small intron (248 bp) w ...[more]

PMID: 9079920

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Dataset Information

Overexpression of a cloned IMP dehydrogenase gene of Candida albicans confers resistance to the specific inhibitor mycophenolic acid.

Publications

Overexpression of a cloned IMP dehydrogenase gene of Candida albicans confers resistance to the specific inhibitor mycophenolic acid.

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