Machine-Learning-Guided Mutagenesis for Directed Evolution of Fluorescent Proteins.

Journal: ACS synthetic biology
Published Date:

Abstract

Molecular evolution based on mutagenesis is widely used in protein engineering. However, optimal proteins are often difficult to obtain due to a large sequence space. Here, we propose a novel approach that combines molecular evolution with machine learning. In this approach, we conduct two rounds of mutagenesis where an initial library of protein variants is used to train a machine-learning model to guide mutagenesis for the second-round library. This enables us to prepare a small library suited for screening experiments with high enrichment of functional proteins. We demonstrated a proof-of-concept of our approach by altering the reference green fluorescent protein (GFP) so that its fluorescence is changed into yellow. We successfully obtained a number of proteins showing yellow fluorescence, 12 of which had longer wavelengths than the reference yellow fluorescent protein (YFP). These results show the potential of our approach as a powerful method for directed evolution of fluorescent proteins.

Authors

  • Yutaka Saito
    National Cancer Center Hospital, Tokyo, Japan (Y.S.).
  • Misaki Oikawa
    Department of Biomolecular Engineering, Graduate School of Engineering , Tohoku University , 6-6-11 Aoba, Aramaki, Aoba-ku , Sendai 980-8579 , Japan.
  • Hikaru Nakazawa
    Department of Biomolecular Engineering, Graduate School of Engineering , Tohoku University , 6-6-11 Aoba, Aramaki, Aoba-ku , Sendai 980-8579 , Japan.
  • Teppei Niide
    Department of Biomolecular Engineering, Graduate School of Engineering , Tohoku University , 6-6-11 Aoba, Aramaki, Aoba-ku , Sendai 980-8579 , Japan.
  • Tomoshi Kameda
    Artificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology (AIST) , 2-4-7 Aomi, Koto-ku , Tokyo 135-0064 , Japan.
  • Koji Tsuda
    Graduate School of Frontier Sciences, The University of Tokyo Kashiwa Chiba 277-8561 Japan.
  • Mitsuo Umetsu
    Department of Biomolecular Engineering, Graduate School of Engineering , Tohoku University , 6-6-11 Aoba, Aramaki, Aoba-ku , Sendai 980-8579 , Japan.