Viability and metal reduction of Shewanella oneidensis MR-1 under CO2 stress: implications for ecological effects of CO2 leakage from geologic CO2 sequestration.
To study potential ecological impacts of CO(2) leakage to shallow groundwater and soil/sediments from geologic CO(2) sequestration (GCS) sites, this work investigated the viability and metal reduction of Shewanella oneidensis MR-1 under CO(2) stress. While MR-1 could grow under high-pressure nitrogen gas (500 psi), the mix of 1% CO(2) with N(2) at total pressures of 15 or 150 psi significantly suppressed the growth of MR-1, compared to the N(2) control. When CO(2) partial pressures were over 15 psi, the growth of MR-1 stopped. The reduced bacterial viability was consistent with the pH decrease and cellular membrane damage under high pressure CO(2). After exposure to 150 psi CO(2) for 5 h, no viable cells survived, the cellular contents were released, and microscopy images confirmed significant cell structure deformation. However, after a relatively short exposure (25 min) to 150 psi CO(2), MR-1 could fully recover their growth within 24 h after the stress was removed, and the reduction of MnO(2) by MR-1 was observed right after the stress was removed. Furthermore, MR-1 survived better if the cells were aggregated rather than suspended, or if pH buffering minerals, such as calcite, were present. To predict the cell viability under different CO(2) pressures and exposure times, a two-parameter mathematical model was developed.
Department of Energy, Environmental and Chemical Engineering, Washington University, St. Louis, Missouri 63130, United States.
Bing
B
Wu
Hongbo
H
Shao
Zhipeng
Z
Wang
Yandi
Y
Hu
Yinjie J
YJ
Tang
Young-Shin
YS
Jun
D002118:Calcium / Q000378:metabolism; D002245:Carbon Dioxide / Q000737:chemistry / Q000633:toxicity*; D057965:Carbon Sequestration; D004785:Environmental Pollutants / Q000737:chemistry / Q000633:toxicity*; D052918:Environmental Restoration and Remediation; D008345:Manganese / Q000378:metabolism; D008670:Metals / Q000378:metabolism*; D050296:Microbial Viability / Q000187:drug effects; D010084:Oxidation-Reduction; D020592:Shewanella / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D013312:Stress, Physiological
D004785:Environmental Pollutants; D008670:Metals; D002245:Carbon Dioxide; D008345:Manganese; D002118:Calcium