A structural model for the GroEL chaperonin.

S Marco; J M Valpuesta; G Rivas; G Andrés; C San Martín; J L Carrascosa

doi:10.1111/j.1574-6968.1993.tb05980.x

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PubMed · 8095912

A structural model for the GroEL chaperonin.

S Marco·J M Valpuesta·G Rivas·G Andrés·C San Martín·J L Carrascosa

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Abstract

Individual particle analysis of end views from negatively stained specimens of purified GroEL from Escherichia coli showed the presence of two different particle populations, those with a six-fold symmetry and those with a seven-fold symmetry, when studied at pH 7.7 and 5.0. Image processing of particles from frozen-hydrated specimens revealed at both pH values a homogeneous population of particles with a strong seven-fold symmetry component and an average image with seven asymmetric units. Biochemical analysis of purified GroEL showed unequivocally the presence of a single polypeptide with the N-terminal sequence identical to that of GroEL. These results are compatible with a structural model of GroEL as an asymmetric aggregate built up by two rings of seven-fold and six-fold symmetries, respectively.

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Amino Acid Sequence Bacterial Proteins Chaperonin 60 Escherichia coli Heat-Shock Proteins Image Processing, Computer-Assisted Microscopy, Electron Models, Molecular Molecular Sequence Data Protein Conformation Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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S Marco, J M Valpuesta, G Rivas, G Andrés, C San Martín, J L Carrascosa. 1993-02-01. A structural model for the GroEL chaperonin.. https://doi.org/10.1111/j.1574-6968.1993.tb05980.x

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