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 (mROLimp) through protein folding memory using a mutated propeptide. The mutated propeptide left its structural memory on mROL and produced mROLimp that exhibited different substrate specificities compared with mROLWT (prepared from the wild type propeptide), although the amino acid sequences of both mROLs were the same. mROLimp showed a preference for substrates with medium chain-length acyl groups and, noticeably, recognized a peptidase-specific substrate. In addition, ROLimp was more stable than mROLWT. 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.