Abstract: Objective To explore the mechanism of Cryptococcus neoformans mutant in CNLAC1 and investigate the difference of CNLAC1 between wild type(Mel⁺) and the mutant (Mel^-).Methods The abnormal PCR DNA product of Cryptococcus neoformans was cloned into sequencing vector PG EM-T for sequencing.An expression vector was constructed for efficient expression in E.coli DH_5α.The gene was sequenced.Results The cloned DNA sequence was found to be different between wild type(Mel⁺) and the mutant (Mel^-)(between 1715 bp and 2617 bp).The differences were not only in length,but also in base sequence.Conclusion The mechanism of the mutant in CNLAC1 might be a change of sequence(between 1715 bp and 2617 bp),and not a DNA deletion.This finding might provide us a target gene for the prognosis and treatment of cryptococcosis.

Key words: Cryptococcus neoformans, CNLAC1