Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.
Infectious Diseases Institute, The Ohio State University, Columbus, Ohio, USA.
Infect Immun. 2021 Oct 15;89(11):e0031021. doi: 10.1128/IAI.00310-21. Epub 2021 Aug 16.
Salmonella enterica serovar Typhi causes chronic infections by establishing biofilms on cholesterol gallstones. The production of extracellular polymeric substances (EPSs) is key to biofilm development, and biofilm architecture depends on which EPSs are made. The presence and spatial distribution of EPSs produced and were investigated in Salmonella enterica serovar Typhimurium and . Typhi biofilms by confocal microscopy. Comparisons between serovars and EPS-mutant bacteria were carried out by examining growth on cholesterol-coated surfaces, with human gallstones in ox or human bile, and in mice with gallstones. On cholesterol-coated surfaces, no major differences in EPS biomass were found between serovars. Cocultured biofilms containing wild-type (WT) and EPS-mutant bacteria demonstrated WT compensation for EPS mutations. Analysis of biofilm EPSs from gallbladder-mimicking conditions found that culture in human bile more consistently replicated the relative abundance and spatial organization of each EPS on gallstones from the chronic mouse model than culture in ox bile. . Typhimurium biofilms cultured on gallstones in ox bile exhibited colocalized pairings of curli fimbriae/lipopolysaccharide and O-antigen capsule/cellulose, while these associations were not present in . Typhi biofilms or in mouse gallstone biofilms. In general, the inclusion of human bile with gallstones replicated biofilm development on gallstones , demonstrating the strength of this model for studying biofilm parameters or EPS-directed therapeutic treatments.
肠炎沙门氏菌血清型 Typhi 通过在胆固醇胆结石上形成生物膜引起慢性感染。胞外聚合物质（EPSs）的产生是生物膜发展的关键，生物膜结构取决于产生的 EPSs 种类。通过共聚焦显微镜研究了肠炎沙门氏菌血清型 Typhimurium 和 Typhi 生物膜中 EPS 的产生和存在及其空间分布。通过在胆固醇包被表面、牛胆汁或人胆汁中的人胆结石以及胆结石小鼠中生长情况，比较了血清型和 EPS 突变细菌之间的差异。在胆固醇包被表面，血清型之间的 EPS 生物量没有发现明显差异。共培养的含有野生型（WT）和 EPS 突变细菌的生物膜显示 WT 对 EPS 突变的补偿。在模拟胆囊条件的生物膜 EPS 分析中发现，在人胆汁中培养比在牛胆汁中培养更能一致地复制慢性小鼠模型胆结石上每种 EPS 的相对丰度和空间组织。在牛胆汁中培养的 Typhimurium 生物膜上，卷曲菌毛/脂多糖和 O 抗原囊/纤维素呈共定位配对，而在 Typhi 生物膜或小鼠胆结石生物膜中则不存在这些关联。总的来说，在胆结石中加入人胆汁可以复制胆结石上的生物膜发育，证明了这种模型在研究生物膜参数或 EPS 靶向治疗方面的强大。
