Cold adaptation of a psychrophilic chaperoninfrom Psychrobacter sp. and its application for heterologousprotein expression

Abstract

Objectives: A chaperonin, PsyGroELS, from the Antarctic psychrophilic bacterium Psychrobacter sp. PAMC21119, was examined for its role in cold adaptation when expressed in a mesophiic Escherichia coli strain. Results: Growth of E. coli harboring PsyGroELS at 10 degree C was increased compared to the control strain. A co-expression system using PsyGroELS was developed to increase productivity of the psychrophilic enzyme PsyEst9. PsyEst9 was cloned and expressed using three E. coli variants that co-expressed GroELS from PAMC21119, E. coli, or Oleispira antarctica RB8T. Co-expression with PsyGroELS was more effective for the production of PsyEst9 compared to the other chaperonins. Conclusion: PsyGroELS confers cold tolerance to E. coli, and shows potential as an effective coexpression system for the stable production of psychrophilic proteins.