N- and C-terminal regions of the small heat shock protein IbpA from Acholeplasma laidlawii competitively govern its oligomerization pattern and chaperone-like activity.

ABSTRACT: Small heat shock proteins (sHSPs) are ubiquitous molecular chaperones preventing the irreversible denaturation of proteins. While in Escherichia coli two sHSPs IbpA and IbpB work in strong cooperation, the sole Mollicute with free-living ability Acholeplasma laidlawii carries a single gene encoding the sHSP protein AlIbpA. In vitro, independently of the temperature, AlIbpA forms a heterogeneous mixture of approximately 24-mer globules, fibrils and huge protein aggregates. The removal of either 12 or 25 N-terminal amino acids led to the formation of fibrils and enhanced the protein ability to prevent the temperature-induced aggregation of insulin, assuming the fibrillar form as an active protein. In turn, the deletion of the C-terminus or substitution of C

SUBMITTER: Chernova LS 

PROVIDER: S-EPMC9050003 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature