Crystal structure and biochemical analysis suggest that YjoB ATPase is a substrate-specific molecular chaperone

Abstract

AAA+ ATPases are ubiquitous proteins associated with most cellular processes, including DNA 15 unwinding and protein unfolding. Their functional and structural properties are typically 16 determined by domains and motifs added to the conserved ATPases domain. Currently, the 17 molecular function and structure of many ATPases remain elusive. Here, we report the crystal 18 structure and biochemical analyses of YjoB, a Bacillus subtilis AAA+ protein. The crystal structure 19 revealed that the YjoB hexamer forms a bucket hat-shaped structure with a porous chamber. 20 Biochemical analyses showed that YjoB prevents the aggregation of vegetative catalase KatA 21 and gluconeogenesis-specific glyceraldehyde-3 phosphate dehydrogenase GapB, but not citrate 22 synthase, a conventional substrate.