GroEL and protein disulfide isomerase each binds with folding intermediates of D-glyceraldehyde-3-phosphate dehydrogenase released from complexes formed with the other.
Simultaneous presence of two chaperones, GroEL and protein disulfide isomerase (PDI), assists the reactivation of denatured D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in an additive way. Delayed addition of chaperones to the refolding solution after dilution of denatured GAPDH indicates an interaction with intermediates formed mainly in the first 5 min for PDI and formed within a longer time period for GroEL-ATP. The above indicate that the two chaperones interact with different folding intermediates of GAPDH. After delayed addition of one chaperone to the refolding mixture containing the other at 4 degrees C, GroEL binds with all GAPDH intermediates dissociated from PDI, and PDI interacts with the intermediates released from GroEL during the first 10-20 min. It is suggested that the GAPDH folding intermediates released from the chaperone-bound complex are still partially folded so as to be rebound by the other chaperone. The above results clearly support the network model of GroEL and PDI.
Zhang
N
N
National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing, China.
Li
J
J
Wang
C
C
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D018834:Chaperonin 60 / Q000378:metabolism*; D004357:Drug Synergism; D005986:Glyceraldehyde 3-Phosphate / Q000378:metabolism; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D008956:Models, Chemical; D018832:Molecular Chaperones / Q000378:metabolism / Q000494:pharmacology; D011485:Protein Binding; D019704:Protein Disulfide-Isomerases / Q000378:metabolism* / Q000494:pharmacology; D017510:Protein Folding; D020673:Protein Renaturation / Q000187:drug effects; D011817:Rabbits; D013997:Time Factors
D018834:Chaperonin 60; D018832:Molecular Chaperones; D005986:Glyceraldehyde 3-Phosphate; D000255:Adenosine Triphosphate; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D019704:Protein Disulfide-Isomerases