title: Dissociation kinetics of the GroEL-gp31 chaperonin complex studied with Förster resonance energy transfer.
abstract: Propagation of bacteriophage T4 in its host Escherichia coli involves the folding of the major capsid protein gp23, which is facilitated by a hybrid chaperone complex consisting of the bacterial chaperonin GroEL and the phage-encoded co-chaperonin, gp31. It has been well established that the GroEL-gp31 complex is capable of folding gp23 whereas the homologous GroEL-GroES complex cannot perform this function. To assess whether this is a consequence of differences in the interactions of the proteins within the chaperonin complex, we have investigated the dissociation kinetics of GroEL-gp31 and GroEL-GroES complexes using Forster resonance energy transfer. Here we report that the dissociation of gp31 from GroEL is slightly faster than that of GroES from GroEL and is further accelerated by the binding of gp23. In contrast to what had been observed previously, we found that gp23 is able to interact with the GroEL-GroES complex, which might explain how bacteriophage T4 redirects the folding machinery of Escherichia coli during morphogenesis.
authors.affiliation: Department of Physics and Astronomy and Laser Centre, VU University, Amsterdam, The Netherlands.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Calmat
authors.forename: Johnny
authors.initials: J
authors.lastname: Hendriks
authors.forename: Harm
authors.initials: H
authors.lastname: van Heerikhuizen
authors.forename: Christoph F
authors.initials: CF
authors.lastname: Schmidt
authors.forename: Saskia M
authors.initials: SM
authors.lastname: van der Vies
authors.forename: Erwin J G
authors.initials: EJ
authors.lastname: Peterman
mesh_terms: D017122:Bacteriophage T4 / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism; D018835:Chaperonin 10 / Q000235:genetics / Q000378:metabolism; D018834:Chaperonin 60 / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods; D007700:Kinetics; D017510:Protein Folding; D025941:Protein Interaction Mapping; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D036022:Capsid Proteins; D018835:Chaperonin 10; D018834:Chaperonin 60; D014764:Viral Proteins; C063473:gene 31 protein, Enterobacteria phage T4; C064517:gp23 protein, Bacteriophage T4