Localization of prefoldin interaction sites in the hyperthermophilic group II chaperonin and correlations between binding rate and protein transfer rate.
Prefoldin is a molecular chaperone that captures a protein-folding intermediate and transfers it to a group II chaperonin for correct folding. The manner by which prefoldin interacts with a group II chaperonin is poorly understood. Here, we have examined the prefoldin interaction site in the archaeal group II chaperonin, comparing the interaction of two Thermococcus chaperonins and their mutants with Pyrococcus prefoldin by surface plasmon resonance. We show that the mutations of Lys250 and Lys256 of Thermococcus alpha chaperonin residues to Glu residues increase the affinity to Pyrococcus prefoldin to the level of Thermococcus beta chaperonin and Pyrococcus chaperonin, indicating that their Glu250 and Glu256 residues of the helical protrusion region are responsible for relatively stronger binding to Pyrococcus prefoldin than Thermococcus alpha chaperonin. Since the putative chaperonin binding sites in the distal ends of Pyrococcus prefoldin are rich in basic residues, electrostatic interaction seems to be important for their interaction. The substrate protein transfer rate from prefoldin correlates well with its affinity for chaperonin.
Zako
Tamotsu
T
Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei-Shi, Tokyo, Japan.
Murase
Yosuke
Y
Iizuka
Ryo
R
Yoshida
Takao
T
Kanzaki
Taro
T
Ide
Naoki
N
Maeda
Mizuo
M
Funatsu
Takashi
T
Yohda
Masafumi
M
D000595:Amino Acid Sequence; D000818:Animals; D019843:Archaeal Proteins / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D002417:Cattle; D018833:Chaperonins / Q000737:chemistry / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding; D019711:Pyrococcus / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D019712:Thermococcus / Q000737:chemistry / Q000378:metabolism
D019843:Archaeal Proteins; D018832:Molecular Chaperones; C112806:prefoldin; D049452:Green Fluorescent Proteins; D018833:Chaperonins