,s Abstract) This proposal seeks to identify new genes which are essential for pathogenesis and could be used as targets for antifungal therapies in the opportunistic fungal pathogen, Cryptococcus neoformans. To identify fungal genes that are essential for pathogenesis. """"""""signature-taged"""""""" mutagenesis, a novel screen which has been highly successful in Salmonella, will be adapted for use in C. neoformans. Mutant strains of C. neoformans will be generated by insertion of a unique """"""""signature- tag"""""""" randomly throughout the genome. The mutant strains will be pooled and injected into a mouse. A strain that fails to proliferate in the animal host will be identified by the absence of its """"""""signature-tag"""""""" in the genomic DNA of the recovered pooled organisms. Strains which are confirmed to be less virulent, will be analyzed throughly and the genes which have been disrupted by the signature tag will be cloned and characterized. Genes that are promising new leads for antifungal targets will be chosen for future characterization.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29AI041962-04
Application #
2887603
Study Section
AIDS and Related Research Study Section 5 (ARRE)
Program Officer
Laughon, Barbara E
Project Start
1997-09-01
Project End
2002-08-31
Budget Start
1999-09-01
Budget End
2000-08-31
Support Year
4
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Saint Louis University
Department
Biochemistry
Type
Schools of Medicine
DUNS #
City
Saint Louis
State
MO
Country
United States
Zip Code
63103
Nelson, Rex T; Pryor, Bryant A; Lodge, Jennifer K (2003) Sequence length required for homologous recombination in Cryptococcus neoformans. Fungal Genet Biol 38:1-9
Nelson, R T; Hua, J; Pryor, B et al. (2001) Identification of virulence mutants of the fungal pathogen Cryptococcus neoformans using signature-tagged mutagenesis. Genetics 157:935-47
Hua, J; Meyer, J D; Lodge, J K (2000) Development of positive selectable markers for the fungal pathogen Cryptococcus neoformans. Clin Diagn Lab Immunol 7:125-8