Proteomic approach and expression analysis revealed the differential expression of predicted leptospiral proteases capable of ECM degradation

Biochim Biophys Acta Proteins Proteom. May-Jun 2018;1866(5-6):712-721. doi: 10.1016/j.bbapap.2018.04.006. Epub 2018 Apr 12.

Abstract

Leptospira, the causative agent of leptospirosis is known to have many proteases with potential to degrade extracellular matrix. However, a multipronged approach to identify, classify, characterize and elucidate their role has not been attempted. Our proteomic approach using high-resolution LC-MS/MS analysis of Triton X-114 fractions of Leptospira interrogans resulted in the identification of 104 proteases out of 130 proteases predicted by MEROPS. In Leptospira approximately 3.5% of the genome complements for proteases, which include catalytic types of metallo-, serine-, cysteine-, aspartic-, threonine- and asparagine- peptidases. Comparison of proteases from different serovars revealed that M04, M09B, M14A, M75, M28A, A01 and U73 protease families are exclusively present in pathogenic form. The M23 and S33 protease families are represented with >14 members in Leptospira. The differential expression under physiological temperature (37 °C) and osmolarity (300 mOsM) showed that proteases belonging to the catalytic type of Metallo-peptidases are upregulated significantly in pathogenic conditions. In silico prediction and characterization of the proteases revealed that several proteases are membrane anchored and secretory, classical as well as non-classical system. The study demonstrates the diversity and complexity of proteases, while maintaining conservation across the serovars in Leptospira and their differential expression under pathogenic conditions.

Keywords: Leptospira; Metalloprotease; Pathogenesis; Protease; Proteomics; Triton X-114.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Chromatography, Liquid
  • Computational Biology
  • Enzyme Stability
  • Extracellular Matrix / metabolism*
  • Extracellular Matrix Proteins / metabolism*
  • Gene Expression Regulation, Bacterial
  • Gene Expression Regulation, Enzymologic
  • Leptospira interrogans / enzymology*
  • Leptospira interrogans / genetics
  • Osmolar Concentration
  • Peptide Hydrolases / genetics
  • Peptide Hydrolases / metabolism*
  • Phylogeny
  • Proteomics / methods*
  • Substrate Specificity
  • Tandem Mass Spectrometry
  • Temperature

Substances

  • Bacterial Proteins
  • Extracellular Matrix Proteins
  • Peptide Hydrolases