Combining co‐culturing of Paenibacillus strains and Vitreoscilla hemoglobin expression as a strategy to improve biodesulfurization

Abstract

Enhancement of the desulfurization activities of Paenibacillus strains 32O‐W and 32O‐Y were investigated using dibenzothiophene (DBT) and DBT sulfone (DBTS) as sources of sulphur in growth experiments. Strains 32O‐W, 32O‐Y and their co‐culture (32O‐W plus 32O‐Y), and Vitreoscilla hemoglobin (VHb) expressing recombinant strain 32O‐Yvgb and its co‐culture with strain 32O‐W were grown at varying concentrations (0·1–2 mmol l−1) of DBT or DBTS for 96 h, and desulfurization measured by production of 2‐hydroxybiphenyl (2‐HBP) and disappearance of DBT or DBTS. Of the four cultures grown with DBT as sulphur source, the best growth occurred for the 32O‐Yvgb plus 32O‐W co‐culture at 0·1 and 0·5 mmol l−1 DBT. Although the presence of vgb provided no consistent advantage regarding growth on DBTS, strain 32O‐W, as predicted by previous work, was shown to contain a partial 4S desulfurization pathway allowing it to metabolize this 4S pathway intermediate.

Improvement in desulfurization of dibenzothiophene and dibenzothiophene sulfone by Paenibacillus strains using immobilization or nanoparticle coating

“…The experiments described here extend our work on DBT and DBTS desulfurization by planktonic cells of Paenibacillus strains 32O-Y and 32O-W (Sar et al, 2021) by investigating whether, for the same growth media and conditions, desulfurization could be enhanced by immobilizing cells or coating cells with Fe 3 O 4 nanoparticles.…”

“…For nanoparticle-coated cells, the maximum OD 600nm was similar to that for planktonic cells (Sar et al, 2021) and about 25% greater than for immobilized cells but differed from both planktonic and immobilized cells in reaching this maximum at 48 h and then decreasing very rapidly (Figure 3a).…”

“…As for DB, the 48 h peak for nanoparticlecoated cells occurred 24 h earlier than for planktonic cells and the rapid decrease in OD 600nm was not seen for planktonic cells. The maximum OD 600nm s for both strains, both immobilized and nanoparticle coated, are as much as 2-3 times lower than those for planktonic cells (Sar et al, 2021; Figure 4).…”

Recent Advances in the Physicochemical Properties and Biotechnological Application of Vitreoscilla Hemoglobin

“…In addition, the co-culture of desulfurization bacteria is also an effective sulfur degradation method [ 84 ]. For example, co-culture of Paenibacillus strains ( vgb + ) showed a stronger growth than the control ( vgb − ) under the conditions of dibenzothiophene [ 11 ]. Moreover, introduction of the vgb gene into Pseudomonas putida can improve its pesticide degradation function under oxygen-limited conditions, including simultaneous degradation of methyl γ-hexachlorocyclohexane and parathion [ 85 ], the removal of 1,2,3-trichloropropane [ 86 ], and the simultaneous elimination of carbamates, pyrethroids, and organophosphates [ 87 ].…”

“…Based on its powerful oxygen transport capacity, VHb has been widely applied in the field of metabolic engineering for microorganisms, plants and animals. By enhancing the regeneration of ATP and NAD + and improving the activity of the TCA cycle [ 7 , 8 ], VHb can be used to promote the growth of microbial, plant and animal cells [ 7 , 9 ], improve the synthesis of target products under oxygen-limited conditions [ 10 ], and increase the effect of microorganisms on bioremediation [ 11 ].…”