Heat Treatment of Small Heat Shock Proteins α-Crystallin and Hsp16.3: Structural Changes vs. Chaperone-like Activity  

作　　者：毛启龙 柯丹霞 昌增益 

出　　处：《Tsinghua Science and Technology》2001年第5期406-409,共4页清华大学学报（自然科学版（英文版）

基　　金：Supported by the National Natural Science Foundation of China ( No.3 970 0 0 2 5 ) and the National Science Foundation for Outstanding Young Scientists in China ( No.3 972 5 0 0 8)

摘　　要：Both α crystallin from bovine eye lens and Hsp16.3 from Mycobacterium tuberculosis are members of the small heat shock protein family. They were preincubated at 100 ℃ for 15 min and then cooled on ice immediately. The chaperone like activities of preheated proteins were measured at 37 ℃ using DTT treated insulin B chains as substrates. Both preheated proteins exhibited greatly enhanced chaperone like activities, accompanied with almost unchanged secondary structures and surface hydrophobicity but with a minor change in tertiary structures. The dramatically enhanced chaperone like activities of preheated α crystallin and Hsp16.3 may have resulted from the irreversible change in the tertiary structure as detected by near UV CD spectra. Both α crystallin from bovine eye lens and Hsp16.3 from Mycobacterium tuberculosis are members of the small heat shock protein family. They were preincubated at 100 ℃ for 15 min and then cooled on ice immediately. The chaperone like activities of preheated proteins were measured at 37 ℃ using DTT treated insulin B chains as substrates. Both preheated proteins exhibited greatly enhanced chaperone like activities, accompanied with almost unchanged secondary structures and surface hydrophobicity but with a minor change in tertiary structures. The dramatically enhanced chaperone like activities of preheated α crystallin and Hsp16.3 may have resulted from the irreversible change in the tertiary structure as detected by near UV CD spectra.

关 键 词：chaperone   activity heat treatment small heat shock protein 

分 类 号：Q51[生物学—生物化学]