Control and functionalization of Escherichia coli flocs as a reaction field

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K18275
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Biofunction/Bioprocess
• Research Institution: Osaka City University (2016); Osaka University (2015)
• Principal Investigator: OJIMA Yoshihiro 大阪市立大学, 大学院工学研究科, 講師 (20546957)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 大腸菌 / フロック / 外膜小胞 / エタノール生産 / Tsf

Outline of Final Research Achievements

In this study, the mechanism of flocculation by bcsB-overexpressed Escherichia coli cells was investigated. Mass spectrometry determination of floc proteins and TEM observation strongly suggested the involvement of outer membrane vesicles (OMVs) during the flocculation. From this point, E. coli flocculation by bcsB overexpression was significantly repressed in hypovesiculation phenotypes. Furthermore, we endowed an ethanol producer, E. coli KO11 strain, with floc-forming ability. During the repeated batch operation, the amount of deposited cells in the flocs from the culture of KO11/bcsB strain was about two times greater than that of KO11 strain, led to the significant increase of ethanol productivity. Finally, a fused protein composed of an elongation factor Ts and GFP successfully expressed on the Escherichia coli flocs. Construction of fused protein with Tsf could be the tool to display heterologous protein on the E. coli floc structure.

Free Research Field

生物化学工学