Associate Professor City University of Hong Kong Hong Kong, Hong Kong
Synthetic biology offers genetically engineered microbes for production of natural chemicals, which show advantages in low cost and rapid scaling for large-scale manufacturing of value compounds. Through a design-build-test cycle paradigm, the secretory phenotypes can be selected in a mutant library for directed evolutions of bio-fabrication[1]. Recently, the microfluidic droplet technology was investigated to successfully demonstrate high throughput single cell secretory screening[2]. However, the assay flexibility was limited[3]. Here, a novel modifiable droplet aptamer alginate microbead (AAM) assay was developed for flexible single microbe secretion screen. Single yeast cells were encapsulated in alginate microbeads for incubation, in which, the conjugated aptamers captured the target secretions to induce the configuration change of aptamer, showing fluorescent signals. The droplet aptamer microbead approach offers a flexible tool to identify critical mutants that can potentially produce a wide range of valuable chemicals towards advanced bio-fabrication.