Title Lack of Photosynthetic Enhancement in Higher

 
Title: Lack of Photosynthetic Enhancement in Higher Plants Expressing Cyanobacterial ictB
Abstract:
This study revisits the 2005 article by Lieman-Hurwitz, which proposed that the expression of the cyanobacterial ictB protein in higher plants could enhance photosynthesis and agricultural yield by elevating CO2 concentrations near the fixation site. The initial article presented limited data, making it challenging to determine the precise conditions under which transgenic plants had an advantage. In this follow-up study, we provide the complete dataset from the original research and perform statistical significance tests at every CO2 concentration point to compare wild-type (wt) and transgenic plants. Our findings indicate that the transgenic plants only showed a significant photosynthetic advantage at CO2 concentrations of 50 and 100 µL L-1, which are too low for normal plant growth. Furthermore, the second generation of transgenic plants, which was previously undisclosed, exhibited no significant difference in photosynthesis compared to wt plants across all CO2 concentrations. In conclusion, the cyanobacterial ictB protein did not improve photosynthesis at most CO2 concentrations and should not be considered an effective agricultural yield enhancer.

Keywords: ictB, photosynthesis enhancement, gas-exchange, transgenic plants.