RRC ID 35603
著者 Hirokawa Y, Kawano H, Tanaka-Masuda K, Nakamura N, Nakagawa A, Ito M, Mori H, Oshima T, Ogasawara N.
タイトル Genetic manipulations restored the growth fitness of reduced-genome Escherichia coli.
ジャーナル J Biosci Bioeng
Abstract Microbes with smaller genomes would be better chassis for analysis, design, and improvement in the fields of metabolic engineering, synthetic biology, and molecular breeding. To create an Escherichia coli strain with a smaller genome, we used a stepwise genome reduction approach. Beginning with strain MGF-01, which has a genome of 3.62 megabase pairs (Mbp), we generated two E. coli K-12 strains without any insertion sequence (IS), DGF-327 and DGF-298, with reduced genome sizes of 3.27 and 2.98 Mbp, respectively. During the strain construction, intrinsic mutations of ilvG and rph were functionally restored to accelerate initial growth after inoculation. The genomes of the two strains were sequenced, and their structures were confirmed. Both strains showed no auxotrophy, and had better growth fitness, especially in the initial phase, and better cell yield in a rich medium than the wild type K-12 strain. Transcriptome analysis revealed that ibpAB and lon, which encode a heat-shock chaperone and a protease for abnormal proteins, respectively, are down-regulated in DGF strains, compared to the ancestral strains with larger genomes. We concluded that down-regulation of the genes encoding chaperones and proteases is one of the factors that improve the fitness of DGF strains. The DGF strains with fewer genes and better cell yield will be good hosts for applications.
巻・号 116(1)
ページ 52-8
公開日 2013-7-1
DOI 10.1016/j.jbiosc.2013.01.010
PII S1389-1723(13)00011-X
PMID 23477741
MeSH DNA Repair Down-Regulation Escherichia coli / genetics* Escherichia coli / growth & development Escherichia coli / metabolism Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism Gene Expression Profiling Genome Size* Genome, Bacterial* Metabolic Engineering* Molecular Chaperones / genetics Molecular Chaperones / metabolism Mutation
IF 2.366
引用数 31
WOS 分野 FOOD SCIENCE & TECHNOLOGY BIOTECHNOLOGY & APPLIED MICROBIOLOGY
リソース情報
原核生物(大腸菌) MGF-01W? DGF-327WΔ234::SC ? DGF-298WΔ100::revΔ234::SC?