Generation of a functionally distinct Rhizopus oryzae lipase through protein folding memory

Abstract

Rhizopus oryzae lipase (ROL) has a propeptide at its N-terminus that functions as an intramolecular chaperone and facilitates the folding of mature ROL (mROL). In this study, we successfully generated a functionally distinct imprinted mROL (mROL imp) through protein folding memory using a mutated propeptide. The mutated propeptide left its structural memory on mROL and produced mROL imp that exhibited different substrate specificities compared with mROL WT (prepared from the wild type propeptide), although the amino acid sequences of both mROLs were the same. mROL imp showed a preference for substrates with medium chain-length acyl groups and, noticeably, recognized a peptidase-specific substrate. In addition, ROL imp was more stable than mROL WT. These results strongly suggest that proteins with identical amino acid sequences can fold into different conformations and that mutations in intramolecular chaperones can dynamically induce changes in enzymatic activity.