PhenoChip: A single-cell phenomic platform for high-throughput photophysiological analyses of microalgae

Area of Science:

• * Aquatic microbiology
• * Photosynthetic microorganisms
• * Bioenergy production

Background:

• * Photosynthetic microorganisms are crucial in aquatic ecosystems and hold potential for bioenergy.
• * Systematic single-cell selection (phenotyping) for improved traits like productivity and stress resilience has been challenging.
• * Current methods limit the ability to analyze and select individual microalgae and cyanobacteria based on specific physiological responses.

Purpose of the Study:

• * To develop a platform, PhenoChip, for multiparametric photophysiological characterization and selection of unicellular phenotypes.
• * To enable user-controlled physicochemical conditions for studying single-cell responses.
• * To facilitate the systematic phenotyping of microalgae and cyanobacteria.

Main Methods:

• * Development of PhenoChip, a platform for single-cell analysis.
• * Application of chlorophyll fluorometry for monitoring single-cell photophysiology.
• * Utilization of optical expulsion technology for single-cell isolation.
• * Exposure of single cells to controlled thermal and chemical treatments.

Main Results:

• * PhenoChip enabled detailed photophysiological characterization of single microalgae cells (Symbiodinium).
• * Identified strain-specific thermal sensitivity and pH optima for photosynthetic performance.
• * Successfully isolated single cells exhibiting enhanced resilience to elevated temperatures.
• * Observed potential transgenerational preservation of photosynthetic phenotypes after single-cell isolation and propagation.

Conclusions:

• * PhenoChip is a versatile platform for single-cell phenotyping of photosynthetic microorganisms.
• * The platform is applicable to fields including biotechnology, ecotoxicology, and assisted evolution.
• * Facilitates the selection of microalgae and cyanobacteria with desirable traits for various applications.