STRUCTURE OF THE HEAT-SHOCK PROTEIN CHAPERONIN-10 OF MYCOBACTERIUM-LEPRAE

Members of the chaperonin-10 (cpn10) protein family, also called heat shock protein 10 and in Escherichia coli GroES, play an important role in ensuring the proper folding of many proteins. The crystal structur e of the Mycobacterium leprae cpn10 (MI-cpn10) oligomer has been eluci dated at a resolution of 3.5 angstroms. The architecture of the MI-cpn 10 heptamer resembles a dome with an oculus in its roof. The inner sur face of the dome is hydrophilic and highly charged. A flexible region, known to interact with cpn60, extends from the lower rim of the dome. With the structure of a cpn10 heptamer now revealed and the structure of the E. coli GroEL previously known, models of cpn10:cpn60 and GroE L:GroES complexes are proposed.