Leptospira spp. strains database implemention by MALDI-TOF-MS and activity analysis of their secreted proteases

• Grant number: 14/18451-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2014
• End date: October 31, 2015
• Field of knowledge: Biological Sciences - Biochemistry - Enzymology
• Principal Investigator: Maria Aparecida Juliano
• Grantee: Daniel Karcher
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated research grant: 12/50191-4 - Synthesis, kinetic studies and applications of substrates and inhibitors for proteolytic enzymes, AP.TEM

Abstract

Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry emerge as the first line techniques for rapid identification of bacteria. In contrast to DNA-based methods, the detection of mass patterns by mass spectrometry does not require reference genome or protein sequences. Due to the reemergence of leptospirosis in non-endemic regions, it is now recognized as a worldwide disease. The clinical findings of this disease are broad and ranges from a mild to a severe infection, the Weil's disease, which can lead to death. Almost every mammal can serve as a carrier of Leptospires. Among the virulence factors the secretion of proteases can contribute to the colonization of the host. Futhermore, proteases play important roles in some vital functions of infectious microorganisms such as replication and processing. The laboratories coordinated by Prof. Dr. Maria Aparecida Juliano studied some metalloproteinases as virulence factor in Leptospires and the question that arises is to determine how the reference spectras (RS) of a collection of Leptospires are correlated with pathogenicity and proteolytic activities. So we will stablish a library of RS by MALDI-TOF-MS based on the collection of Leptospires from Faculty of Veterinary Medicine in University of São Paulo (USP) and study the proteolytic activity of proteases secreted by 10 of their strains using FRET peptides. (AU)