Spitzer ED, Spitzer SG; American Society for Microbiology. Meeting.
Abstr Annu Meet Am Soc Microbiol. 1991 May 5-9; 91: 421 (abstract no. F-80).
Dept. of Pathology, SUNY at Stony Brook, Stony Brook, NY.
C. neoformans is a leading cause of life-threatening infections in patients with AIDS. The ability to identify and analyze genetic differences among clinical isolates of C. neoformans would contribute to a better understanding of the virulence properties of this environmentally acquired pathogen. We have isolated several cDNA clones that identify restriction fragment length polymorphisms (RFLPs) in C. neoformans var. neoformans (serotypes A and D) and in clinical isolates from a single geographic region. Strain variation was analyzed by Southern hybridization. To isolate cryptococcal DNA, spheroplaste were prepared with Novozym 234, and nucleic acids purified by conventional procedures except for an additional extraction step with cetyl trimethylammonium bromide which eliminated capsular polysaccharides that inhibit certain restriction enzymes. Probe c6 from a C. neoformans cDNA library hybridized to a single 3.8 kb Bglll fragment in 2 serotype A strains and in 4 c. neoformans isolated from AIDS patients seen at one hospital in the New York area. Fragments of 7 to 23 kb were seen in 3 other clinical isolates from the New York area, and 5 strains belonging to serotypes A, D, and C. The 3 serotype A strains were distinguishable from 3 serotype D strains. A 13 kb genomic clone containing c6 hybridized to 1-5 polymophic fragments indicating the presence of rearrangements or extensive sequence divergence in this region. A similar pattern of variation was seen with other cDNA probes. Differences between strains were also detected by pulsed field gel electrophoresis. This RFLP analysis using probes from several locl reveals substantial genetic variation within var. neoformans and suggests that groups of strains may have limited geographic distributions.
Publication Types:
Keywords:
- Base Sequence
- Chromosomes
- Cryptococcus neoformans
- Humans
- New York
- Polymorphism, Restriction Fragment Length
- Variation (Genetics)
- Virulence
- genetics
Other ID:
UI: 102181578
From Meeting Abstracts