Mutations responsible for alcohol tolerance in the mutant of Synechococcus elongatus PCC 7942 (SY1043) obtained by single-cell screening system

Yasutaka Hirokawa; Yu Kanesaki; Sayuri Arai; Fumiko Saruta; Kayoko Hayashihara; Akio Murakami; Kazunori Shimizu; Hiroyuki Honda; Hirofumi Yoshikawa; Taizo Hanai

doi:10.1016/j.jbiosc.2017.11.012

Mutations responsible for alcohol tolerance in the mutant of Synechococcus elongatus PCC 7942 (SY1043) obtained by single-cell screening system

J Biosci Bioeng. 2018 May;125(5):572-577. doi: 10.1016/j.jbiosc.2017.11.012.

Authors

Affiliations

¹ Laboratory for Bioinformatics, Graduate School of Systems Life Sciences, Kyushu University, 804 Westwing, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
² NODAI Genome Research Center, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan.
³ Department of Biotechnology, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
⁴ Kobe University Research Center for Inland Seas, 2746 Iwaya, Awaji, Hyogo 656-2401, Japan.
⁵ Department of Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan.
⁶ Laboratory for Bioinformatics, Graduate School of Systems Life Sciences, Kyushu University, 804 Westwing, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. Electronic address: taizo@brs.kyushu-u.ac.jp.

PMID: 29269101
DOI: 10.1016/j.jbiosc.2017.11.012

Abstract

The production of alcohols directly from carbon dioxide by engineered cyanobacteria is an attractive technology for a sustainable future. Enhanced tolerance to the produced alcohols would be a desirable feature of the engineered cyanobacterial strains with higher alcohol productivity. We have recently obtained the mutant strains of Synechococcus elongatus PCC 7942 with higher tolerance to isopropanol using a single-cell screening system (Arai et al., Biotechnol. Bioeng., 114, 1771-1778, 2017). Among the mutant strains, SY1043 showed the highest isopropanol tolerance. Interestingly, SY1043 also showed higher tolerance to other alcohols such as ethanol and 1-butanol, however, the mechanisms involved in enhancing this alcohol tolerance were unclear. To reveal the alcohol tolerance mechanism of SY1043, we investigated the relationship between alcohol tolerance and four mutations found in SY1043 by genome resequencing analysis. Isopropanol tolerance was enhanced by amino acid substitution (Leu285Pro) in a hypothetical protein encoded by Synpcc7942_0180 of the wild type strain TA1297. TA4135, into which this mutation was introduced, showed a same tendency of tolerance to other alcohols (ethanol and 1-butanol).

Keywords: Alcohol tolerance; Cyanobacteria; Genome resequencing analysis; Isopropanol; NADP(H).

MeSH terms

2-Propanol / metabolism*
Adaptation, Biological / genetics*
Carbon Dioxide / metabolism
DNA Mutational Analysis
Drug Resistance, Bacterial / genetics
Ethanol / metabolism
High-Throughput Screening Assays / methods*
Mutation*
Organisms, Genetically Modified
Single-Cell Analysis / methods*
Synechococcus / genetics*
Synechococcus / metabolism*

Substances

Carbon Dioxide
Ethanol
2-Propanol