Folding and maturation of phage P22 tailspike protein in Escherichia coli strains carrying mutations in heat shock response

Abstract

The involvement of Escherichia coli molecular chaperones, GroE and DnaK proteins, in the folding and maturation of the phage P22 tailspike protein was examined. The yield of mature tailspike did not increase in the presence of excess groE gene products. Furthermore the tailspike protein folded and matured normally in an Escherichia coli host strain carrying a mutation in the groEL or dnaK gene. However, in a host strain (rpoH~) which does not have a functional heat shock transcriptional foe切r sigma32, the yield of mature tailspike was reduced substantially. The results suggest that folding and maturation of the P22 tailspike protein should require unidentified molecular chaperone(s) under the regulation of sigma32 protein.