A Regulatory Role of Molecular Chaperones in Excited States and Functions of Folded Enzymes

Molecular chaperones are recognized for assisting protein folding. Emerging evidence suggests that chaperones also interact with natively folded proteins. Yet their functional impact on folded proteins remains unclear. Here, we show that chaperones can directly modulate the conformational dynamics and catalytic efficiency of enzymes in their native states. Spy and Hsp70 increased lysozyme activity by altering conformational exchanges, and this effect extended across other chaperones and enzymes. Hsp70, Spy, Hsp104, and Hsp20 enhanced the catalytic activities of multiple folded enzymes, including alkaline phosphatase, DNA polymerase Pfu, endonucleases Cas12a/Cas13a, and xylanase. These findings uncover an unanticipated function of chaperones in regulating enzyme function expanding their mechanistic scope beyond folding assistance and suggests opportunities in enzyme engineering, diagnostics, and cellular regulation.