High-throughput screening for industrial enzyme production hosts by droplet microfluidics
Journal article, 2014

A high-throughput method for single cell screening by microfluidic droplet sorting is applied to a whole-genome mutated yeast cell library yielding improved production hosts of secreted industrial enzymes. The sorting method is validated by enriching a yeast strain 14 times based on its a-amylase production, close to the theoretical maximum enrichment. Furthermore, a 105 member yeast cell library is screened yielding a clone with a more than 2-fold increase in a-amylase production. The increase in enzyme production results from an improvement of the cellular functions of the production host in contrast to previous droplet-based directed evolution that has focused on improving enzyme protein structure. In the workflow presented, enzyme producing single cells are encapsulated in 20 pL droplets with a fluorogenic reporter substrate. The coupling of a desired phenotype (secreted enzyme concentration) with the genotype (contained in the cell) inside a droplet enables selection of single cells with improved enzyme production capacity by droplet sorting. The platform has a throughput over 300 times higher than that of the current industry standard, an automated microtiter plate screening system. At the same time, reagent consumption for a screening experiment is decreased a million fold, greatly reducing the costs of evolutionary engineering of production strains.

DIRECTED EVOLUTION

MICRODROPLETS

SACCHAROMYCES-CEREVISIAE

Author

S. L. Sjostrom

Royal Institute of Technology (KTH)

Y. Bai

Royal Institute of Technology (KTH)

Mingtao Huang

Chalmers, Chemical and Biological Engineering, Life Sciences, System Biology

Zihe Liu

Chalmers, Chemical and Biological Engineering, Life Sciences, System Biology

Jens B Nielsen

Chalmers, Chemical and Biological Engineering, Life Sciences, System Biology

H. N. Joensson

Royal Institute of Technology (KTH)

H. A. Svahn

Royal Institute of Technology (KTH)

Lab on a Chip - Miniaturisation for Chemistry and Biology

1473-0197 (ISSN) 1473-0189 (eISSN)

Vol. 14 4 806-813

Subject Categories

Industrial Biotechnology

Chemical Engineering

Areas of Advance

Life Science Engineering (2010-2018)

DOI

10.1039/c3lc51202a

More information

Latest update

2/26/2018