In this study, we aimed at identifying the regulatory role of marT gene, known as the regulator of misL, on 15 different biofilm-related genes in S. Typhimurium 14028 strain. We also tested the strains for their ability to form biofilm and determined the adherence characteristics of the wild type and the mutant strains of the organism on Caco-2 and HEp-2 cells. For comparative analyses of the candidate genes, individual gene mutations were created via antibiotic gene cassette insertion into each gene of interest. marT gene was cloned behind an arabinose inducible BAD promoter in order to control marT expression. This recombinant plasmid was transfer into each of the 15 mutant strains to investigate the level of expression of each single gene in the presence and absence of marT induction. Besides determination of variations in biofilm formation by each mutant strain, the attachment characteristics of them onto Caco-2 and HEp-2 cell lines were also reported. As a result of attachments experiments on polystyrene surfaces, it was determined that the biofilm production capacity of each mutant strain decreased in a statistically significant manner (p < 0.05). QRT-PCR trials indicated that the marT gene regulates the expression of 14 genes, namely fimA, fimD, fimF, fimH, stjB, stjC, csgA, csgD, ompC, sthB, sthE, rmbA, fliZ and yaiC, in a positive manner. QRT-PCR studies were also revealed that the MarT protein positively regulates its own promoter. When the adherence characteristics of the mutant strains and the wild-type were investigated by using Caco-2 and HEp-2 cells, it was determined that the single gene mutations did have no effect on bacterial adhesion. In view of our mutational analyses and biofilm formation studies, it was concluded that fliZ, ompC, rmbA, stjB and stjC genes are related with biofilm formation in Salmonella, besides other cellular functions of them. Taken together, our data suggested that the regulatory role of MarT protein is not only restricted to the regulation of misL gene expression, but it rather acts as a general regulator on the biofilm-related genes in Salmonella.

在这项研究中，我们旨在确定的调控作用MART基因，被称为调节MISL中，在15个不同的生物膜相关基因S.鼠伤寒沙门氏菌菌株14028。我们还测试了菌株形成生物膜的能力，并确定了野生型的粘附特性以及该生物在Caco-2和HEp-2细胞上的突变菌株。为了对候选基因进行比较分析，通过将抗生素基因盒插入到每个目标基因中来创建单个基因突变。MART基因在为了控制阿拉伯糖诱导型启动子BAD后面克隆MART表达。将该重组质粒转移到15个突变菌株中的每一个中，以研究在存在和不存在marT诱导的情况下每个单个基因的表达水平。除了确定每种突变菌株在生物膜形成中的变化外，还报道了它们在Caco-2和HEp-2细胞系上的附着特性。在聚苯乙烯表面上进行附着实验的结果是，确定了每个突变菌株的生物膜生产能力均以统计学上显着的方式下降（p <0.05）。QRT-PCR试验表明marT基因可调控14个基因的表达，即fimA，fimD，fimF，fimH，stjB，stjC，csgA，csgD，ompC，sthB，sthE，rmbA，fliZ和yaiC。QRT-PCR研究还揭示了MarT蛋白正向调节其自身的启动子。当通过使用Caco-2和HEp-2细胞研究突变菌株和野生型的粘附特性时，确定单基因突变对细菌粘附没有影响。鉴于我们的突变分析和生物膜形成研究，得出的结论是fliZ，ompC，rmbA，stjB沙门氏菌和stjC基因除了与沙门氏菌的其他细胞功能有关外，还与沙门氏菌的生物膜形成有关。两者合计，我们的数据表明MarT蛋白的调节作用不仅限于对misL基因表达的调节，而且还可以作为沙门氏菌生物膜相关基因的一般调节剂。