Urease: production of recombinant protein and development of inhibitors for antifungal therapy against cryptococcosis

• Grant number: 24/02673-7
• Support Opportunities: Regular Research Grants
• Start date: June 01, 2024
• End date: May 31, 2026
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Mobility Program: SPRINT - Projetos de pesquisa - Mobilidade
• Principal Investigator: Kelly Ishida
• Grantee: Kelly Ishida
• Principal researcher abroad: Angela Gelli
• Institution abroad: University of California, Davis (UC Davis), United States
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 23/12190-0 - Molecules with antifungal potential on Candida and Cryptococcus and investigation of mechanisms of action: inhibition and cell death, AP.R

Abstract

Cryptococcus species are etiological agents of cryptococcosis, the cerebral form is the most frequent and severe in HIV/AIDS patients, resulting in high rates of mortality and morbidity. Although antifungal therapy for cryptococcosis is available, it is still ineffective due to the limited antifungal option, side effects, unfavorable pharmacokinetics, and the increase of isolates resistant to available antifungals. Therefore, our research group has been searching new alternatives for the treatment of cryptococcosis, one of which is the development of inhibitors of the Cryptococcus urease enzyme. Urease catalyzes the hydrolysis of urea into ammonia, which is associated with increased yeast survival within macrophages and the weakening of the blood-brain barrier that facilitates the entry of the pathogen into brain tissue, an important step in the establishment of cryptococcal meningitis. Considering that urease is naturally absent in humans, enzyme inhibition could be an interesting strategy for the development of anti-Cryptococcus agents; however, its three-dimensional structure is not yet known. Therefore, this project aims to produce a recombinant urease from C. neoformans using the eukaryotic expression system Pichia pastoris to characterize and elucidate its structure. This will greatly facilitate the development of potent inhibitors to investigate antifungal activity in vitro and in vivo in the search for alternative therapeutics for the treatment of cryptococcosis. (AU)