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Microfluidic high-throughput selection of microalgal strains with superior photosynthetic productivity using competitive phototaxis.

ABSTRACT: Microalgae possess great potential as a source of sustainable energy, but the intrinsic inefficiency of photosynthesis is a major challenge to realize this potential. Photosynthetic organisms evolved phototaxis to find optimal light condition for photosynthesis. Here we report a microfluidic screening using competitive phototaxis of the model alga, Chlamydomonas reinhardtii, for rapid isolation of strains with improved photosynthetic efficiencies. We demonstrated strong relationship between phototaxis and photosynthetic efficiency by quantitative analysis of phototactic response at the single-cell level using a microfluidic system. Based on this positive relationship, we enriched the strains with improved photosynthetic efficiency by isolating cells showing fast phototactic responses from a mixture of 10,000 mutants, thereby greatly improving selection efficiency over 8 fold. Among 147 strains isolated after screening, 94.6% showed improved photoautotrophic growth over the parental strain. Two mutants showed much improved performances with up to 1.9- and 8.1-fold increases in photoautotrophic cell growth and lipid production, respectively, a substantial improvement over previous approaches. We identified candidate genes that might be responsible for fast phototactic response and improved photosynthesis, which can be useful target for further strain engineering. Our approach provides a powerful screening tool for rapid improvement of microalgal strains to enhance photosynthetic productivity.

SUBMITTER: Kim JY

PROVIDER: S-EPMC4745075 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Microfluidic high-throughput selection of microalgal strains with superior photosynthetic productivity using competitive phototaxis.

Kim Jaoon Young Hwan JY Kwak Ho Seok HS Sung Young Joon YJ Choi Hong Il HI Hong Min Eui ME Lim Hyun Seok HS Lee Jae-Hyeok JH Lee Sang Yup SY Sim Sang Jun SJ

Scientific reports 20160208

Microalgae possess great potential as a source of sustainable energy, but the intrinsic inefficiency of photosynthesis is a major challenge to realize this potential. Photosynthetic organisms evolved phototaxis to find optimal light condition for photosynthesis. Here we report a microfluidic screening using competitive phototaxis of the model alga, Chlamydomonas reinhardtii, for rapid isolation of strains with improved photosynthetic efficiencies. We demonstrated strong relationship between phot ...[more]

PMID: 26852806

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Microfluidic high-throughput selection of microalgal strains with superior photosynthetic productivity using competitive phototaxis.

Publications

Microfluidic high-throughput selection of microalgal strains with superior photosynthetic productivity using competitive phototaxis.

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