The study, posted online January 13 in Science Express, revealed differences in the virulence strategies used by C. neoformans compared to other pathogenic fungi. Researchers also examined the genetic determinants of its pathogenicity by comparing the genomes of two closely related strains of significantly different virulence.
"Not only have we established a genomic platform for the further study of this increasingly important pathogen, but the data from the two strains may provide insight into what determines virulence," says Brendan Loftus, a scientist at The Institute for Genomic Research (TIGR) who is the first author of the Science paper. "Although the two Cryptococcus strains we examined differ significantly in virulence, we found surprisingly little difference in their gene content."
TIGR scientists led by primary investigator Claire M. Fraser, the President of TIGR, deciphered the genome of one strain of C. neoformans while researchers led by Richard Hyman at Stanford University's Genome Technology Center in Palo Alto, CA, sequenced the second strain. The project was funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. Numerous collaborators helped to interpret and analyze the genome sequence data.
C. neoformans, an oval-shaped yeast, is an opportunistic human pathogen of global importance that is used by researchers as a model for fungal pathogenesis. Since the 1980s, the number of Cryptococcus infections has increased sharply mainly among people