title: BeF(x) stops the chaperonin cycle of GroEL-GroES and generates a complex with double folding chambers.
abstract: Coupling with ATP hydrolysis and cooperating with GroES, the double ring chaperonin GroEL assists the folding of other proteins. Here we report novel GroEL-GroES complexes formed in fluoroberyllate (BeF(x)) that can mimic the phosphate part of the enzyme-bound nucleotides. In ATP, BeF(x) stops the functional turnover of GroEL by preventing GroES release and produces a symmetric 1:2 GroEL-GroES complex in which both GroEL rings contain ADP.BeF(x) and an encapsulated substrate protein. In ADP, the substrate protein-loaded GroEL cannot bind GroES. In ADP plus BeF(x), however, it can bind GroES to form a stable 1:1 GroEL-GroES complex in which one of GroEL rings contains ADP.BeF(x) and an encapsulated substrate protein. This 1:1 GroEL-GroES complex is converted into the symmetric 1:2 GroEL-GroES complex when GroES is supplied in ATP plus BeF(x). Thus, BeF(x) stabilizes two GroEL-GroES complexes; one with a single folding chamber and the other with double folding chambers. These results shed light on the intermediate ADP.P(i) nucleotide states in the functional cycle of GroEL.
authors.affiliation: Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Taguchi
authors.forename: Keigo
authors.initials: K
authors.lastname: Tsukuda
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Motojima
authors.forename: Ayumi
authors.initials: A
authors.lastname: Koike-Takeshita
authors.forename: Masasuke
authors.initials: M
authors.lastname: Yoshida
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001608:Beryllium / Q000494:pharmacology*; D018835:Chaperonin 10 / Q000737:chemistry / Q000378:metabolism*; D018834:Chaperonin 60 / Q000737:chemistry / Q000378:metabolism*; D005459:Fluorides / Q000494:pharmacology*; D006868:Hydrolysis; D017510:Protein Folding
chemical_list: D018835:Chaperonin 10; D018834:Chaperonin 60; C035982:beryllium fluoride; D000255:Adenosine Triphosphate; D001608:Beryllium; D005459:Fluorides