Localization of Prefoldin Interaction Sites in the Hyperthermophilic Group II Chaperonin and Correlations between Binding Rate and Protein Transfer Rate

• Published in: Journal of molecular biology Vol. 364; no. 1; pp. 110 - 120
• Main Authors: Zako, Tamotsu, Murase, Yosuke, Iizuka, Ryo, Yoshida, Takao, Kanzaki, Taro, Ide, Naoki, Maeda, Mizuo, Funatsu, Takashi, Yohda, Masafumi
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 17.11.2006
• Subjects: Amino Acid Sequence; Animals; archaea; Archaeal Proteins - chemistry; Archaeal Proteins - metabolism; Binding Sites; Cattle; chaperonin; Chaperonins - chemistry; Chaperonins - metabolism; Green Fluorescent Proteins - chemistry; Green Fluorescent Proteins - metabolism; Humans; Models, Molecular; Molecular Chaperones - chemistry; Molecular Chaperones - metabolism; Molecular Sequence Data; prefoldin; Protein Binding; Protein Conformation; Protein Folding; protein–protein interaction; Pyrococcus; Pyrococcus - chemistry; Pyrococcus - metabolism; Sequence Alignment; Thermococcus; Thermococcus - chemistry; Thermococcus - metabolism; CPN; CPNαK250E/K256E; prefoldin; PhPFD; T. KS-1; CPNβdel; PFDL69C; protein–protein interaction; CPNαK250E; CPNβ; CPNα; archaea; FL-PFD; GFP; CPNαK256E; SPR; chaperonin; protein folding; CPNβαα; CPNαββ; PhCPN
• ISSN: 0022-2836; 1089-8638
• DOI: 10.1016/j.jmb.2006.08.088

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 α chaperonin residues to Glu residues increase the affinity to Pyrococcus prefoldin to the level of Thermococcus β 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 α 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.