Genetic engineering of the Calvin cycle toward enhanced photosynthetic CO2 fixation in microalgae

Autor: Bo Yang, Jin Liu, Xiaonian Ma, Bingbing Guo, Bin Liu, Tao Wu, Yue Jiang, Feng Chen
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Biotechnology for Biofuels, Vol 10, Iss 1, Pp 1-13 (2017)
Druh dokumentu: article
ISSN: 1754-6834
DOI: 10.1186/s13068-017-0916-8
Popis: Abstract Background Photosynthetic microalgae are emerging as potential biomass feedstock for sustainable production of biofuels and value-added bioproducts. CO2 biomitigation through these organisms is considered as an eco-friendly and promising alternative to the existing carbon sequestration methods. Nonetheless, the inherent relatively low photosynthetic capacity of microalgae has hampered the practical use of this strategy for CO2 biomitigation applications. Results Here, we demonstrate the feasibility of improving photosynthetic capacity by the genetic manipulation of the Calvin cycle in the typical green microalga Chlorella vulgaris. Firstly, we fused a plastid transit peptide to upstream of the enhanced green fluorescent protein (EGFP) and confirmed its expression in the chloroplast of C. vulgaris. Then we introduced the cyanobacterial fructose 1,6-bisphosphate aldolase, guided by the plastid transit peptide, into C. vulgaris chloroplast, leading to enhanced photosynthetic capacity (~ 1.2-fold) and cell growth. Molecular and physiochemical analyses suggested a possible role for aldolase overexpression in promoting the regeneration of ribulose 1,5-bisphosphate in the Calvin cycle and energy transfer in photosystems. Conclusions Our work represents a proof-of-concept effort to enhance photosynthetic capacity by the engineering of the Calvin cycle in green microalgae. Our work also provides insights into targeted genetic engineering toward algal trait improvement for CO2 biomitigation uses.
Databáze: Directory of Open Access Journals