Pyridoxal kinase PdxY mediated carbon dioxide assimilation to enhance the biomass in Chlamydomonas reinhardtii CC-400. (February 2021)

• Record Type: Journal Article
• Authors: Lin, Jia-Yi; Xue, Chengfeng; Tan, Shih-I; Ng, I-Son
• Is Part Of: Bioresource technology. Volume 322(2021)
• Publication Date: 2021-02
• Subjects: Carbon dioxide utilization -- Chlamydomonas reinhardtii -- Mixotrophic culture -- Pyridoxal kinase -- Carbonic anhydrase; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2020.124530
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Pyridoxal kinase (PdxY) is the first time to be cloned and transformed to CC-400. The biomass and CO2 assimilation have been reported in different reactors. PY9 had the significant enhancement of biomass and CO2 fixation in photo-bioreactor. PY9 modulated the activity of carbonic anhydrase and reduced CO2 emission. PdxY has high potential used in microalgae to increase biomass intrinsically. Abstract: Microalga served as the promising bioresources due to the high efficiency of carbon dioxide conversion. However, the application of microalga is still restricted by low biomass, easier contamination, and high cost of production. To overcome the challenge, engineered Chlamydomonas reinhardtii CC-400 with pyridoxal kinase gene ( pdxY ) has demonstrated in this study. The results indicated CC-400 with pdxY reached enhanced algal biomass in three different systems, including flask, Two-layer Photo-Reactor (TPR) and airlift Photo-Bioreactor (PBR). The genetic strain PY9 cultured with 1% CO2 in the PBR showed a significant enhancement of biomass up to 1.442 g/L, a 2-times of that of the wild type. We also found the transcriptional levels of carbonic anhydrase (CA) dropped down in PY9 while higher levels of RuBisCo and pdxY occurred, thus the carbon dioxide assimilation under mixotrophic culture dramatically increased. We proofed that pdxY successfully mediated carbon dioxide utilization in CC-400.