New findings on how pathogenic baceria protect against our immune system

NMBU researchers at the Faculty of Chemistry, Biotechnology and Food Science (KBM), have shown that a popular biomass degrading enzyme, the lytic polysaccharide monooxygenases (LPMOs), promote virulence in multi-drug resistant Pseudomonas aeruginosa.

 The multi-disciplinary study, published February 23 2021 in Nature Communications, was conducted by Dr. Fatemeh Askarian and Prof. Vaaje-Kolstad in close collaboration with several exceptional national and international scientists, in particular Prof. Victor Nizet and his laboratory from the University of California San Diego.  

 The discovery of the lytic polysaccharide monooxygenases (LPMOs) in 2010 by NMBU researchers revolutionized the field of biomass degradation and these enzymes soon became favorites among many researchers.

 Despite several indications in the literature, the potential roles of LPMOs in pathogenesis has remained ambiguous.

Moonlighting enzymes

In 2018 Askarian and Vaaje-Kolstad initiated a project to elucidate the functional properties of the highly conserved and prevalent chitin-active LPMO in Pseudomonas aeruginosa, called CbpD. In their recent study they show that this protein promotes P. aeruginosa virulence in the context of systemic infection via attenuating the terminal complement cascade, an important arm of the innate immunity.

These results raise the possibility that LPMOs act as moonlighting enzymes, i.e. having dual functionality: one in polysaccharide conversion and another in immune evasion.

The authors expect that their findings can have a significant impact for research on redox-active virulence factors and their roles in bacterial pathogenesis, and may ultimately contribute to the development of novel anti-virulence therapies.

The project was funded in part by the Norwegian Research Council and the Faculty of Chemistry, Biotechnology and Food Science (KBM), NMBU.

Published 23. February 2021 - 19:30 - Updated 7. January 2022 - 19:00