Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13, West 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-04 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan.
Water Res. 2016 May 15;95:383-91. doi: 10.1016/j.watres.2016.04.018. Epub 2016 Apr 12.
We demonstrated the genotype-dependent removal of human norovirus particles with a microfiltration (MF) membrane in the presence of bacteria bearing histo-blood group antigens (HBGAs). Three genotypes (GII.3, GII.4, and GII.6) of norovirus-like particles (NoVLPs) were mixed with three bacterial strains (Enterobacter sp. SENG-6, Escherichia coli O86:K61:B7, and Staphylococcus epidermidis), respectively, and the mixture was filtered with an MF membrane having a nominal pore size of 0.45 μm. All NoVLP genotypes were rejected by the MF membrane in the presence of Enterobacter sp. SENG-6, which excreted HBGAs as extracellular polymeric substances (EPS). This MF membrane removal of NoVLPs was not significant when EPS was removed from cells of Enterobacter sp. SENG-6. GII.6 NoVLP was not rejected with the MF membrane in the presence of E. coli O86:K61:B7, but the removal of EPS of E. coli O86:K61:B7 increased the removal efficiency due to the interaction of NoVLPs with the exposed B-antigen in lipopolysaccharide (LPS) of E. coli O86:K61:B7. No MF membrane removal of all three genotypes was observed when S. epidermidis, an HBGA-negative strain, was mixed with NoVLPs. These results demonstrate that the location of HBGAs on bacterial cells is an important factor in determining the genotype-dependent removal efficiency of norovirus particles with the MF membrane. The presence of HBGAs in mixed liquor suspended solids from a membrane bioreactor (MBR) pilot plant was confirmed by immune-transmission electron microscopy, which implies that bacterial HBGAs can contribute to the genotype-dependent removal of human noroviruses with MBR using MF membrane.
我们证明了在带有携带组织血型抗原（HBGA）的细菌存在的情况下，微孔滤膜（MF）可以去除具有基因型依赖性的人类诺如病毒颗粒。将三种基因型（GII.3、GII.4 和 GII.6）的诺如病毒样颗粒（NoVLPs）分别与三种细菌菌株（肠杆菌属 SENG-6、大肠杆菌 O86:K61:B7 和表皮葡萄球菌）混合，并用标称孔径为 0.45 μm 的 MF 膜进行过滤。在肠杆菌属 SENG-6 存在的情况下，所有 NoVLP 基因型都被 MF 膜排斥，肠杆菌属 SENG-6 分泌 HBGA 作为细胞外聚合物质（EPS）。当从肠杆菌属 SENG-6 细胞中去除 EPS 时，MF 膜对 NoVLPs 的去除作用并不显著。在大肠杆菌 O86:K61:B7 的存在下，GII.6 NoVLP 不受 MF 膜排斥，但由于 NoVLPs 与大肠杆菌 O86:K61:B7 脂多糖（LPS）中暴露的 B 抗原相互作用，去除大肠杆菌 O86:K61:B7 的 EPS 会增加去除效率。当将 HBGA 阴性菌株表皮葡萄球菌与 NoVLPs 混合时，没有观察到所有三种基因型的 MF 膜去除。这些结果表明，HBGA 在细菌细胞上的位置是决定 MF 膜对诺如病毒颗粒具有基因型依赖性去除效率的重要因素。通过免疫传输电子显微镜证实了膜生物反应器（MBR）中试工厂混合液悬浮固体中存在 HBGA，这意味着细菌 HBGA 可以有助于使用 MF 膜的 MBR 对人类诺如病毒进行基因型依赖性去除。
