Modification of carbon metabolism in Synechococcus elongatus PCC 7942 by cyanophage-derived sigma factors for bioproduction improvement

Naruhiko Sawa, Tsuneyuki Tatsuke, Atsushi Ogawa, Yasutaka Hirokawa, Takashi Osanai, Taizo Hanai

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)

Abstract

Many cyanophages, which infect cyanobacteria, most of possess putative sigma factors that have high amino acid sequence homology with the σ70-type sigma factor present in cyanobacteria, allowing them to obtain energy and metabolites for their own propagation. In this study, we aimed to modify the carbon metabolism of Synechococcus elongatus PCC 7942 by expressing putative sigma factors from Synechococcus phages to improve bioproduction. Four cyanophage-derived putative sigma factors—putative RpsD4 from Synechococcus phage S-CBS1, putative RpoD and putative RpoS from S-CBS2, and putative RpsD4 from S-CBS3—were selected for this purpose. These were introduced into S. elongatus PCC 7942, and their expression was controlled with a theophylline-dependent riboswitch. The expression of the putative RpoD from S-CBS2 and putative RpsD4 from S-CBS3 resulted in a significant decrease in the growth rate of S. elongatus PCC 7942. In addition, metabolome analysis showed a 3.2-fold increase in acetyl-CoA concentration with the expression of the putative RpoD from S-CBS2 and a 1.9-fold increase with the putative RpsD4 from S-CBS3. The results of RT-qPCR showed that several sugar metabolism genes were repressed by the putative RpoD and activated by the putative RpsD4. In particular, the engineered strain overexpressing the putative RpsD4 and expressing phosphate acetyltransferase succeeded in improving the productivity of the model target product acetate to 217% of its previous value. To the best of our knowledge, this study is the first to modify the metabolism of S. elongatus PCC 7942 by expressing their putative sigma factors from cyanophages.

Original languageEnglish
Pages (from-to)256-264
Number of pages9
JournalJournal of Bioscience and Bioengineering
Volume127
Issue number2
DOIs
Publication statusPublished - Feb 2019

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Bioengineering
  • Applied Microbiology and Biotechnology

Fingerprint Dive into the research topics of 'Modification of carbon metabolism in Synechococcus elongatus PCC 7942 by cyanophage-derived sigma factors for bioproduction improvement'. Together they form a unique fingerprint.

Cite this