Haloferax mediterranei Halolysin R4 Confers Antagonistic and Defensive Capabilities
Shaoxing Chen, Siqi Sun, Rui Wang, Hongli Feng, Hua Xiang
Abstract
provides its host antagonistic and defensive activities against other haloarchaea, which expands our knowledge on the traditional function of haloarchaeal extracellular proteases. Haloarchaeal extracellular serine proteases have been previously discussed as growth-phase-dependent proteins, whereas our study reports constitutive expression of halolysin R4. This work also clearly reveals a hidden diversity of extracellular proteases from haloarchaea. Studies on multifunctional halolysins reveal that they play an important ecological role in shaping microbial community composition and provide a new perspective towards understanding the intricate interactions between haloarchaeal cells in hypersaline environments. HlyR4 can lyse competing cells living in the same environment, and the cell debris may probably be utilized as nutrients, which may constitute an important part of nutrient cycling in extremely hypersaline environments.