Types of microbial aggregates have essential effects on bacterial communities’ characteristics, thus affecting the pollutants removal. An up-flow biofilm reactor was used to study the different performances of S^2-/NO₂^– removal and functional genes in suspended sludge and biofilms. The metabolic pathways of sulfurous and nitrogenous pollutants in the desulfurization-denitrification process were proposed. The results showed that S⁰ formation dominated the reactor with a high S^2- concentration. Autotrophic Sulfurovum responsible for S^2-/S⁰ oxidation was the only dominant bacteria in suspended sludge. Heterotrophic Desulfocapsa responsible for SO₄^2- reduction coexisted with Sulfurovum and dominated in biofilms. S^2- oxidation to S⁰ was catalyzed via fccA/B and sqr genes in suspended sludge. S₃^2-/S⁰ oxidation to SO₄^2- was catalyzed via dsrA/B gene in biofilms. SO₄^2- and NO₂^– were removed via the dissimilatory sulfate reduction and denitrification pathway, respectively. This work provides a fundamental and practical basis for optimizing suspended sludge/biofilm systems for S^2-/NO₂^– removal.

微生物聚集体的类型对细菌群落的特征有重要影响，从而影响污染物的去除。上流式生物膜反应器用于研究悬浮污泥和生物膜中S ^2- /NO ₂ ^-去除和功能基因的不同性能。提出了脱硫脱硝过程中含硫和含氮污染物的代谢途径。结果表明，S ⁰形成在具有高S ^2-浓度的反应器中占主导地位。负责S ^2- /S ⁰氧化的自养Sulfurovum是悬浮污泥中唯一的优势细菌。异养脱硫藻负责 SO ₄ ^2-还原与Sulfurovum共存并在生物膜中占主导地位。S ^2-氧化为S ⁰是通过悬浮污泥中的fccA/B 和sqr 基因催化的。S ₃ ^2- /S ⁰氧化为SO ₄ ^2-是通过生物膜中的dsrA/B 基因催化的。SO ₄ ^2-和NO ₂ ^-分别通过异化硫酸盐还原和反硝化途径去除。这项工作提供了用于优化悬浮污泥/生物膜系统与S的基本和实践基础^2- / NO ₂ ^-的去除。