Patterning and transferring hydrogel-encapsulated bacterial cells for quantitative analysis of synthetically engineered genetic circuits.
We describe a hydrogel patterning and transferring (HPT) method that facilitates the quantitative analysis of synthetically engineered genetic circuits within bacterial cells. The HPT method encapsulates cells in the alginate hydrogel patterns by using polydimethylsiloxane (PDMS) template. Then, the hydrogel-encapsulated cell patterns are transferred onto an agarose hydrogel substrate that encapsulates inducer chemicals or bacterial cells. Using the HPT method, we demonstrate that inducers in the agarose hydrogel substrate regulate gene expression of the patterned cells for qualitative analysis by activating the promoters of fluorescence protein genes. In addition, we demonstrate that the HPT method can be used for the analysis of the cross-talk between genetic circuits and the concentration-dependent gene expression and regulation because the agarose hydrogel substrate can produce concentration gradients of inducers. Lastly, we demonstrate that the HPT method can be applied to investigating intercellular communication between neighboring cells with a wide range of cell densities. Since the HPT method is simple to deal with but versatile and powerful to quantitatively analyze genetic circuits in living cells in many controllable manners, we believe that the method can be widely used for the rapid advancement of synthetic, molecular, and systems biology.
School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology, 100 Banyeon-ri, Ulsan 689-798, Republic of Korea.
Woon Sun
WS
Choi
Minseok
M
Kim
Seongyong
S
Park
Sung Kuk
SK
Lee
Taesung
T
Kim
D000464:Alginates / Q000737:chemistry; D001431:Bacteriological Techniques / Q000379:methods; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D053263:Gene Regulatory Networks; D005818:Genetic Engineering / Q000379:methods*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry*; D010957:Plasmids; D012685:Sepharose / Q000737:chemistry
D000464:Alginates; D004129:Dimethylpolysiloxanes; D006603:Hexuronic Acids; D020100:Hydrogels; C013830:baysilon; D020723:Glucuronic Acid; D012685:Sepharose