TY - JOUR
T1 - Endogenous biohydrogen from a rhizobium-legume association drives microbial biodegradation of polychlorinated biphenyl in contaminated soil
AU - Xu, Yongfeng
AU - Teng, Ying
AU - Wang, Xiaomi
AU - Ren, Wenjie
AU - Zhao, Ling
AU - Luo, Yongming
AU - Christie, Peter
AU - Greening, Chris
N1 - Funding Information:
We thank H. Yao and Y. Zhu (Institute of Urban Environment, Chinese Academy of Sciences) for guiding the method of DNA-SIP experiment. This research was supported by the National Key Research and Development Program of China (2019YFC1803705), the National Natural Science Foundation of China (42130718, 42207030, 41991335, 41907138), the Jiangsu Funding Program for Excellent Postdoctoral Talent (2022ZB465), the China Postdoctoral Science Foundation (2022M723241), the Youth Fund of Jiangsu Province (BK20191106), and the National Science and Technology Innovation Leading Talents Program (SQ2022RA24910167).
Funding Information:
We thank H. Yao and Y. Zhu (Institute of Urban Environment, Chinese Academy of Sciences) for guiding the method of DNA-SIP experiment. This research was supported by the National Key Research and Development Program of China (2019YFC1803705), the National Natural Science Foundation of China (42130718, 42207030, 41991335, 41907138), the Jiangsu Funding Program for Excellent Postdoctoral Talent (2022ZB465), the China Postdoctoral Science Foundation (2022M723241), the Youth Fund of Jiangsu Province (BK20191106), and the National Science and Technology Innovation Leading Talents Program (SQ2022RA24910167).
Publisher Copyright:
© 2023 The Author(s)
PY - 2023/6
Y1 - 2023/6
N2 - Endogenous hydrogen (H2) is produced through rhizobium-legume associations in terrestrial ecosystems worldwide through dinitrogen fixation. In turn, this gas may alter rhizosphere microbial community structure and modulate biogeochemical cycles. However, very little is understood about the role that this H2 leaking to the rhizosphere plays in shaping the persistent organic pollutants degrading microbes in contaminated soils. Here, we combined DNA-stable isotope probing (DNA-SIP) with metagenomics to explore how endogenous H2 from the symbiotic rhizobium-alfalfa association drives the microbial biodegradation of tetrachlorobiphenyl PCB 77 in a contaminated soil. The results showed that PCB77 biodegradation efficiency increased significantly in soils treated with endogenous H2. Based on metagenomes of 13C-enriched DNA fractions, endogenous H2 selected bacteria harboring PCB degradation genes. Functional gene annotation allowed the reconstruction of several complete pathways for PCB catabolism, with different taxa conducting successive metabolic steps of PCB metabolism. The enrichment through endogenous H2 of hydrogenotrophic Pseudomonas and Magnetospirillum encoding biphenyl oxidation genes drove PCB biodegradation. This study proves that endogenous H2 is a significant energy source for active PCB-degrading communities and suggests that elevated H2 can influence the microbial ecology and biogeochemistry of the legume rhizosphere.
AB - Endogenous hydrogen (H2) is produced through rhizobium-legume associations in terrestrial ecosystems worldwide through dinitrogen fixation. In turn, this gas may alter rhizosphere microbial community structure and modulate biogeochemical cycles. However, very little is understood about the role that this H2 leaking to the rhizosphere plays in shaping the persistent organic pollutants degrading microbes in contaminated soils. Here, we combined DNA-stable isotope probing (DNA-SIP) with metagenomics to explore how endogenous H2 from the symbiotic rhizobium-alfalfa association drives the microbial biodegradation of tetrachlorobiphenyl PCB 77 in a contaminated soil. The results showed that PCB77 biodegradation efficiency increased significantly in soils treated with endogenous H2. Based on metagenomes of 13C-enriched DNA fractions, endogenous H2 selected bacteria harboring PCB degradation genes. Functional gene annotation allowed the reconstruction of several complete pathways for PCB catabolism, with different taxa conducting successive metabolic steps of PCB metabolism. The enrichment through endogenous H2 of hydrogenotrophic Pseudomonas and Magnetospirillum encoding biphenyl oxidation genes drove PCB biodegradation. This study proves that endogenous H2 is a significant energy source for active PCB-degrading communities and suggests that elevated H2 can influence the microbial ecology and biogeochemistry of the legume rhizosphere.
KW - Biodegradation
KW - Biohydrogen
KW - Legume-rhizobium symbiosis
KW - Polychlorinated biphenyls
KW - Soil
KW - Stable isotope probing
UR - http://www.scopus.com/inward/record.url?scp=85159938442&partnerID=8YFLogxK
U2 - 10.1016/j.envint.2023.107962
DO - 10.1016/j.envint.2023.107962
M3 - Article
C2 - 37196568
AN - SCOPUS:85159938442
SN - 0160-4120
VL - 176
JO - Environment International
JF - Environment International
M1 - 107962
ER -
