Hydrophobic dye inhibits aggregation of molten carbonic anhydrase during thermal unfolding and refolding

Citation
B. Kundu et P. Guptasarma, Hydrophobic dye inhibits aggregation of molten carbonic anhydrase during thermal unfolding and refolding, PROTEINS, 37(3), 1999, pp. 321-324
Citations number
20
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
PROTEINS-STRUCTURE FUNCTION AND GENETICS
ISSN journal
0887-3585 → ACNP
Volume
37
Issue
3
Year of publication
1999
Pages
321 - 324
Database
ISI
SICI code
0887-3585(19991115)37:3<321:HDIAOM>2.0.ZU;2-W
Abstract
Association-seeking surfaces on partially structured polypeptides can parti cipate in interactions that are either intramolecular (folding related) or intermolecular (aggregative). During heat shock, intermolecular association s leading to aggregation are prevented through the binding of such surfaces by chaperones of the Hsp20 family (with Hsp70 later effecting release and refolding). Here we report that the hydrophobic dye, 8-anilino-1-naphthalen esulfonate (ANS), mimics the function of the chaperones in its interactions with molten carbonic anhydrase (CA),At 150-fold molar excess of dye over p rotein, heat-induced aggregation of CA is almost completely inhibited by bi nding of ANS to solvent-exposed clusters of nonpolar residues. After exposu re of ANS-containing protein solutions to temperatures as high as 95 degree s C, refolded CA can be recovered through cooling and dialysis, with no acc ompanying aggregation. This apparent mimicking of chaperone activity by a s mall dye opens up new approaches to understanding and manipulating protein aggregation. Proteins 1999;37:321-324. (C) 1999 Wiley-Liss, Inc.