ClpL Chaperone as a Possible Component of the Disaggregase Activity of Limosilactobacillus fermentum U-21

Strain L. fermentum U-21 secretes chaperones into the medium and it is considered as the candidate for the development of drugs, so-called disaggregases, for Parkinsons disease therapy. This study is devoted to characterization of secreted protein encoded by C0965₀00195 locus. Analysis of sequence and predicted structure of the protein encoded by C0965₀00195 allows us to attribute it to the ClpL, homologs of which are known to be chaperones. The chaperone activity of ClpL L. fermentum U-21 was evaluated in vivo by refolding of differing in thermostability luciferases from Aliivibrio fischeri and Photorhabdus luminescens in Escherichia coli cells. It was observed that clpL from L. fermentum U-21 can compensate for the deficiency in the clpB gene and enhance the ability to refold thermodenatured proteins in clpB- cells. In vitro experiments have demonstrated the ability of a spent culture medium containing proteins secreted by L. fermentum U-21 cells, including ClpL, to prevent thermodenaturation of luciferases partially. We suggest that the ClpL protein from L. fermentum U-21 strain, which exhibits disaggregase properties against aggregating proteins, may be one of the clue components that play a role in the pharmabiotic properties of this strain.