Download MendeleyA bipartite bacterial virulence factor targets the complement system and neutrophil activation.
Kurniyati, K., Clark, N.D., Wang, H., Deng, Y., Sze, C.W., Visser, M.B., Malkowski, M.G., Li, C.(2025) EMBO J 44: 1154-1184
- PubMed: 39753953
- DOI: https://doi.org/10.1038/s44318-024-00342-8
- Primary Citation of Related Structures:
9ARC - PubMed Abstract:
The complement system and neutrophils constitute the two main pillars of the host innate immune defense against infection by bacterial pathogens. Here, we identify T-Mac, a novel virulence factor of the periodontal pathogen Treponema denticola that allows bacteria to evade both defense systems. We show that T-Mac is expressed as a pre-protein that is cleaved into two functional units. The N-terminal fragment has two immunoglobulin-like domains and binds with high affinity to the major neutrophil chemokine receptors FPR1 and CXCR1, blocking N-formyl-Met-Leu-Phe- and IL-8-induced neutrophil chemotaxis and activation. The C-terminal fragment functions as a cysteine protease with a unique proteolytic activity and structure, which degrades several components of the complement system, such as C3 and C3b. Murine infection studies further reveal a critical T-Mac role in tissue damage and inflammation caused by bacterial infection. Collectively, these results disclose a novel innate immunity-evasion strategy, and open avenues for investigating the role of cysteine proteases and immunoglobulin-like domains of gram-positive and -negative bacterial pathogens.
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, VA, USA.
Organizational Affiliation:
