The exploration of hydrogen production promoting mechanism of Rhodobacter sphaeroides by expressing tetA under tetracycline stress

Photo-fermentative hydrogen production rate improving has been a key limiting link in the field of biological hydrogen production by photosynthetic bacterium (PSB) in recent years. In our previous study, apparent hydrogen production enhancement was observed in R. sphaeroides HY01 with tetA expressed under tetracycline (Tc), which attracted our interests. It was found that Tc-resistant strains always presented stable hydrogen production pro-motion on the maximum hydrogen production rate (Rm), which was approximately 30% with Tc addition. Figuring out the underlying connections between Tc resistance and hydrogen production of R. sphaeroides may provide new methods for obtaining engineered PSB with high hydrogen production performance. In this study, basing on experimental tests, hydrogen promotion of resistant strain was found to be Tc dose-dependent. Some relevant gene expression differences on hydrogen production of Rodobacter sphaeroides induced by the expression of TetA and the addition of Tc were also tested and discussed. (c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

Improving the rate of photo-fermentative hydrogen production has been a major challenge in the field of biological hydrogen production using photosynthetic bacteria (PSB) in recent years. In a previous study, it was observed that the expression of tetA gene in R. sphaeroides HY01 under tetracycline (Tc) led to significant enhancement of hydrogen production. Further investigation revealed that Tc-resistant strains consistently showed stable promotion of hydrogen production rate (Rm), with approximately 30% promotion with Tc addition. This study explores the Tc dose-dependent hydrogen promotion of resistant strains and investigates the gene expression differences induced by TetA expression and Tc addition in Rodobacter sphaeroides.