Format

Send to

Choose Destination
Biotechnol J. 2018 Jul;13(7):e1700497. doi: 10.1002/biot.201700497. Epub 2018 Mar 26.

Genome Variations of Evolved Escherichia coli ET8 With a Rhodopsin-Based Phototrophic Metabolism.

Author information

1
Hana Academy Seoul, Seoul, Republic of Korea.
2
Department of Biological Sciences, Seoul National University, Seoul, Korea.
3
Department of Systems Biotechnology, Chung-Ang University, Anseong, Gyeonggi, Republic of Korea.
4
Department of Biotechnology, the Catholic University of Korea, Bucheon, Gyeonggi, Republic of Korea.
5
Department of Life Science, Sogang University, Seoul, Republic of Korea.
6
Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Republic of Korea.

Abstract

We reported that the phototrophic metabolism via plasmid-originated Gloeobacter rhodopsin(GR)-expression is improved in Escherichia coli ET5 harboring pKJ606-GR by a genomic point mutation (dgcQC1082A ) encoding a transmembrane cell signaling protein (Microb. Cell Fact. 16:111, 2017). Another evolved descendant is isolated from the chemostat, and the genome variation of the strain named ET8 harboring pKJ606-GR is investigated in this study. Whole genome sequencing analysis identifies a single point mutation (C3831976A) located in the non-coding upstream region of kdtA and an IS4 insertional mutation at galUG706 without any mutations in the plasmid. ET8 strain shows enhanced kdtA transcription and no growth in the D-galactose or lactose sole carbon sourced minimal media. Size of ET8 strain are almost identical to that of the ancestor. Phototrophic growth and proton pumping in ET8 expressing GR (ET8 + GR) are increased 1.5-fold and threefold, respectively, compared with those in the ancestor (W3110 + GR). To verify the effects of the genomic mutations, either the kdtA-upregulation or the galU-disruption is conducted in the ancestor. Both the kdtA-upregulation and the galU-disruption result in the drastic increases of proton-pumping. The physiological properties arising from the genomic variations of the evolved host with the new phototrophic metabolism are further discussed.

KEYWORDS:

Gloeobacter rhodopsin; adaptive laboratory evolution; chemotroph; galU-disruption; kdtA-upregulation; phototroph

PMID:
29469946
DOI:
10.1002/biot.201700497
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center