Mirolase, a novel subtilisin-like serine protease from the periodontopathogen Tannerella forsythia.

Published

Journal Article

The genome of Tannerella forsythia, an etiological factor of chronic periodontitis, contains several genes encoding putative proteases. Here, we characterized a subtilisin-like serine protease of T. forsythia referred to as mirolase. Recombinant full-length latent promirolase [85 kDa, without its signal peptide (SP)] processed itself through sequential autoproteolytic cleavages into a mature enzyme of 40 kDa. Mirolase latency was driven by the N-terminal prodomain (NTP). In stark contrast to almost all known subtilases, the cleaved NTP remained non-covalently associated with mirolase, inhibiting its proteolytic, but not amidolytic, activity. Full activity was observed only after the NTP was gradually, and fully, degraded. Both activity and processing was absolutely dependent on calcium ions, which were also essential for enzyme stability. As a consequence, both serine protease inhibitors and calcium ions chelators inhibited mirolase activity. Activity assays using an array of chromogenic substrates revealed that mirolase specificity is driven not only by the substrate-binding subsite S1, but also by other subsites. Taken together, mirolase is a calcium-dependent serine protease of the S8 family with the unique mechanism of activation that may contribute to T. forsythia pathogenicity by degradation of fibrinogen, hemoglobin, and the antimicrobial peptide LL-37.

Full Text

Cited Authors

  • Ksiazek, M; Karim, AY; Bryzek, D; Enghild, JJ; Thøgersen, IB; Koziel, J; Potempa, J

Published Date

  • March 2015

Published In

Volume / Issue

  • 396 / 3

Start / End Page

  • 261 - 275

PubMed ID

  • 25391881

Pubmed Central ID

  • 25391881

Electronic International Standard Serial Number (EISSN)

  • 1437-4315

International Standard Serial Number (ISSN)

  • 1431-6730

Digital Object Identifier (DOI)

  • 10.1515/hsz-2014-0256

Language

  • eng