Regulation of bacteria population behaviors by AI-2 "consumer cells" and "supplier cells"

• Published in: BMC microbiology 2017-09, Vol.17 (1), p.198-198, Article 198
• Main Authors: Quan, Yufen, Meng, Fankang, Ma, Xinyu, Song, Xinhao, Liu, Xiao, Gao, Weixia, Dang, Yulei, Meng, Yao, Cao, Mingfeng, Song, Cunjiang
• Format: Article
• Language: English
• Subjects: Antimicrobial agents; Autorinducer-2; Bacteria; Bacteria - growth & development; Bacteria - metabolism; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Biofilm; Biofilms; Biofilms - drug effects; Biofilms - growth & development; Carbon-Sulfur Lyases - genetics; Carbon-Sulfur Lyases - metabolism; Cell regulation; Cell signaling; Consumer cells; E coli; Escherichia coli; Escherichia coli - genetics; Escherichia coli - growth & development; Escherichia coli - physiology; Escherichia coli Proteins - genetics; Escherichia coli Proteins - metabolism; Fluorescence; Gene expression; Gene Expression Regulation, Bacterial; Genes, Bacterial; Genetic aspects; Green fluorescent protein; Homoserine - analogs & derivatives; Homoserine - analysis; Homoserine - genetics; Homoserine - metabolism; Lactones - analysis; Lactones - metabolism; Ligands (Biochemistry); LuxS protein; Metabolism; Metabolites; Microbiological research; Microorganisms; Phosphorylation; Plasmids; Properties; Strains (organisms); Supplier cells
• ISSN: 1471-2180; 1471-2180
• DOI: 10.1186/s12866-017-1107-2

Autoinducer-2 (AI-2) is a universal signal molecule and enables an individual bacteria to communicate with each other and ultimately control behaviors of the population. Harnessing the character of AI-2, two kinds of AI-2 "controller cells" ("consumer cells" and "supplier cells") were designed to "reprogram" the behaviors of entire population. For the consumer cells, genes associated with the uptake and processing of AI-2, which includes LsrACDB, LsrFG, LsrK, were overexpressed in varying combinations. Four consumer cell strains were constructed: Escherichia coli MG1655 pLsrACDB (NK-C1), MG1655 pLsrACDBK (NK-C2), MG1655 pLsrACDBFG (NK-C3) and MG1655 pLsrACDBFGK (NK-C4). The key enzymes responsible for production of AI-2, LuxS and Mtn, were also overexpressed, yielding strains MG1655 pLuxS (NK-SU1), and MG1655 pLuxS-Mtn (NK-SU2). All the consumer cells could decrease the environmental AI-2 concentration. NK-C2 and NK-C4 were most effective in AI-2 uptake and inhibited biofilm formation. While suppliers can increase the environmental AI-2 concentration and NK-SU2 was most effective in supplying AI-2 and facilitated biofilm formation. Further, reporter strain, MG1655 pLGFP was constructed. The expression of green fluorescent protein (GFP) in reporter cells was initiated and guided by AI-2. Mixture of consumer cells and reporter cells suggest that consumer cells can decrease the AI-2 concentration. And the supplier cells were co-cultured with reporter cells, indicating that supplier cells can provide more AI-2 compared to the control. The consumer cells and supplier cells could be used to regulate environmental AI-2 concentration and the biofilm formation. They can also modulate the AI-2 concentration when they were co-cultured with reporter cells. It can be envisioned that this system will become useful tools in synthetic biology and researching new antimicrobials.