{Reference Type}: Journal Article
{Title}: Biohydrogen utilization in legume-rhizobium symbiosis reveals a novel mechanism of accelerated tetrachlorobiphenyl transformation.
{Author}: Xu Y;Teng Y;Wang X;Wang H;Li Y;Ren W;Zhao L;Wei M;Luo Y;
{Journal}: Bioresour Technol
{Volume}: 404
{Issue}: 0
{Year}: 2024 Jul 31
{Factor}: 11.889
{DOI}: 10.1016/j.biortech.2024.130918
{Abstract}: Symbiosis between Glycine max and Bradyrhizobium diazoefficiens were used as a model system to investigate whether biohydrogen utilization promotes the transformation of the tetrachlorobiphenyl PCB77. Both a H2 uptake-positive (Hup+) strain (wild type) and a Hup- strain (a hupL deletion mutant) were inoculated into soybean nodules. Compared with Hup- nodules, Hup+ nodules increased dechlorination significantly by 61.1 % and reduced the accumulation of PCB77 in nodules by 37.7 % (p < 0.05). After exposure to nickel, an enhancer of uptake hydrogenase, dechlorination increased significantly by 2.2-fold, and the accumulation of PCB77 in nodules decreased by 54.4 % (p < 0.05). Furthermore, the tetrachlorobiphenyl transformation in the soybean root nodules was mainly testified to be mediated by nitrate reductase (encoded by the gene NR) for tetrachlorobiphenyl dechlorination and biphenyl-2,3-diol 1,2-dioxygenase (bphC) for biphenyl degradation. This study demonstrates for the first time that biohydrogen utilization has a beneficial effect on tetrachlorobiphenyl biotransformation in a legume-rhizobium symbiosis.