Generation of a Functionally Distinct Rhizopus oryzae Lipase through Protein Folding Memory.

Atsushi Satomura,Mitsuyoshi Ueda,Kouichi Kuroda

doi:10.1371/journal.pone.0124545

Atsushi Satomura, Mitsuyoshi Ueda + Show 1 more

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https://doi.org/10.1371/journal.pone.0124545

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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.

Highlights

Most lipases and proteases are produced as precursor forms with propeptides and are subsequently processed into mature enzymes [1,2,3,4]
We demonstrated that mutations in propeptide of ROL (proROL) led to “protein folding memory” and generated a functionally distinct imprinted mature ROL (mROL) that had the same amino acid sequence as mROL prepared from wild-type proROL
Our previous study revealed that residues Ser38–Glu57 of proROL were essential for the folding of mROL [6]

Summary

Introduction

Most lipases and proteases are produced as precursor forms with propeptides and are subsequently processed into mature enzymes [1,2,3,4]. Some propeptides function as inhibitors that temporarily inhibit the enzymatic activities of their mature enzymes during cellular transport [5]. Some propeptides play an essential role in protein maturation. These propeptides function as chaperones and facilitate the correct folding of their mature enzymes [6, 7]. Because propeptides are covalently bound to the mature enzyme, they are called “intramolecular chaperones,” distinct from “intermolecular chaperones.”. Once the protein has been folded into its mature form, propeptides are removed by autolysis or exogenous proteases [5, 8] Because propeptides are covalently bound to the mature enzyme, they are called “intramolecular chaperones,” distinct from “intermolecular chaperones.” Once the protein has been folded into its mature form, propeptides are removed by autolysis or exogenous proteases [5, 8]

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