Optimization of Light and Nutrients Supply to Stabilize Long-Term Industrial Cultivation of Metabolically Engineered Cyanobacteria: A Model-Based Analysis

An automated high-throughput lighting system for screening photosynthetic microorganisms in plate-based formats

The capacity of photosynthetic microorganisms to fix carbon dioxide into biomass positions them as promising cell factories for sustainable biomanufacturing. However, limitations in screening throughput hinder the identification of enzymes, strains, and growth conditions needed to realize this potential. Here we present a microplate-based high-throughput cultivation system that can be integrated into existing automation infrastructure and supports growth of both prokaryotic and eukaryotic photosynthetic microorganisms. We validate this system by optimizing BG-11 medium compositions for Synechococcus elongatus UTEX 2973, Chlamydomonas reinhardtii UTEX 90 and Nostoc hatei CUBC1040, resulting in growth rates increases of 38.4% to 61.6%. We also identify small molecules that influence growth rates in Synechococcus elongatus UTEX 2973, including candidate compounds for growth rate increase and dozens that prevent growth. The sensitivity, throughput, and extensibility of this system support screening, strain isolation, and growth optimization needed for the development of photosynthetic microbial cell factories.

Nutraceutical prospects of genetically engineered cyanobacteria- technological updates and significance

Genetically engineered cyanobacterial strains that have improved growth rate, biomass productivity, and metabolite productivity could be a better option for sustainable bio-metabolite production. The global demand for biobased metabolites with nutraceuticals and health benefits has increased due to their safety and plausible therapeutic and nutritional utility. Cyanobacteria are solar-powered green cellular factories that can be genetically tuned to produce metabolites with nutraceutical and pharmaceutical benefits. The present review discusses biotechnological endeavors for producing bioprospective compounds from genetically engineered cyanobacteria and discusses the challenges and troubleshooting faced during metabolite production. This review explores the cyanobacterial versatility, the use of engineered strains, and the techno-economic challenges associated with scaling up metabolite production from cyanobacteria. Challenges to produce cyanobacterial bioactive compounds with remarkable nutraceutical values have been discussed. Additionally, this review also summarises the challenges and future prospects of metabolite production from genetically engineered cyanobacteria as a sustainable approach.