A continuous flow membrane bio-reactor releases the feedback inhibition of self-generated free organic carbon on cbb gene transcription of a typical chemoautotrophic bacterium to improve its CO2 fixation efficiency

Saiwei Zhang; Lei Wang; Xiaohua Fu; Yiu Fai Tsang; Kanchan Maiti

doi:10.1016/j.scitotenv.2020.143186

A continuous flow membrane bio-reactor releases the feedback inhibition of self-generated free organic carbon on cbb gene transcription of a typical chemoautotrophic bacterium to improve its CO₂ fixation efficiency

Sci Total Environ. 2021 Mar 20:761:143186. doi: 10.1016/j.scitotenv.2020.143186. Epub 2020 Oct 21.

Authors

Saiwei Zhang¹, Lei Wang², Xiaohua Fu³, Yiu Fai Tsang⁴, Kanchan Maiti⁵

Affiliations

¹ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, China; Department of Oceanography and Coastal Sciences, College of the Coast and Environment, Louisiana State University, Baton Rouge, LA, USA.
² State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, China. Electronic address: celwang@tongji.edu.cn.
³ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, China.
⁴ Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, New Territories, Hong Kong SAR, China.
⁵ Department of Oceanography and Coastal Sciences, College of the Coast and Environment, Louisiana State University, Baton Rouge, LA, USA.

PMID: 33131832
DOI: 10.1016/j.scitotenv.2020.143186

Abstract

Since the free organic carbon (FOC) generated by chemoautotrophic bacterium self has a feedback inhibition effect on its growth and carbon fixation, a continuous flow membrane bio-reactor was designed to remove extracellular FOC (EFOC) and release its inhibition effect. The promotion effect of membrane reactor on growth and carbon fixation of typical chemoautotrophic bacterium and its mechanism were studied. The accumulated apparent carbon fixation yield in membrane reactor was 3.24 times that in the control reactor. The EFOC per unit bacteria and cbb gene transcription level in membrane reactor were about 0.41 times and 11.18 times that in control reactor in late stage, respectively. Membrane reactor separated out EFOC, especially the small molecules, which facilitated the release of intracellular FOC, thereby releasing the inhibition of FOC on cbb gene transcription, thus promoting growth and carbon fixation of the typical chemoautotrophic bacterium. This study lays a foundation for enhancing carbon fixation by chemoautotrophic bacteria and expands the application field of membrane reactor.

Keywords: CO(2) fixation; Chemoautotrophic bacterium; Continuous flow membrane bio-reactor; Free organic carbon; cbb gene.

MeSH terms

Bacteria / genetics
Carbon Dioxide*
Carbon*
Feedback
Transcription, Genetic

Substances

Carbon Dioxide
Carbon