RT Journal Article
SR Electronic
T1 McsB forms a gated kinase chamber to mark aberrant bacterial proteins for degradation
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.09.08.287243
DO 10.1101/2020.09.08.287243
A1 Bence Hajdusits
A1 Marcin J. Suskiewicz
A1 Nikolas Hundt
A1 Anton Meinhart
A1 Robert Kurzbauer
A1 Julia Leodolter
A1 Philipp Kukura
A1 Tim Clausen
YR 2020
UL http://biorxiv.org/content/early/2020/09/08/2020.09.08.287243.abstract
AB In Gram-positive bacteria, the McsB protein arginine kinase is central to protein quality control, labelling aberrant molecules for degradation by the ClpCP protease. Despite its importance for stress response and pathogenicity, it is still elusive how the bacterial degradation labelling is regulated. Here, we delineate the mechanism how McsB targets aberrant proteins during stress conditions. Structural data reveal a self-compartmentalized kinase, in which the active sites are sequestered in a molecular cage. The “closed” octamer interconverts with other oligomers in a phosphorylation-dependent manner and, contrary to these “open” forms, preferentially labels unfolded proteins. In vivo data show that heat-shock triggers accumulation of higher-order oligomers, of which the octameric McsB is essential for surviving stress situations. The interconversion of open and closed oligomers represents a distinct regulatory mechanism of a degradation labeler, allowing the McsB kinase to adapt its potentially dangerous enzyme function to the needs of the bacterial cell.Competing Interest StatementThe authors have declared no competing interest.