Impaired colonization by and full invasiveness of Escherichia coli K1 bearing a site-directed mutation in the type 1 pilin gene.
Impaired colonization by and full invasiveness of Escherichia coli K1 bearing a site-directed mutation in the type 1 pilin gene.
复制标题
带有 1 型菌毛蛋白基因定点突变的大肠杆菌 K1 的定植和完全侵袭性受损。
DOI：
10.1128/iai.58.1.275-278.1990
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发表时间：
1990
影响因子：
3.1
通讯作者：
Orndorff,PE
中科院分区：
文献类型：
--
作者：
Bloch,CA;Orndorff,PE
通过对编码1型菌毛主要结构亚基的基因Pila进行定向突变，构建了系统侵袭性大肠杆菌K1株的1型菌毛缺陷突变株。通过将该突变株与同基因的Pila+菌株进行比较，我们能够评估1型菌毛在新生大鼠消化道定植和血流侵袭中的作用。肠道定植不受Pila突变的显著影响；相反，1型的丧失与口咽定植的显著减少相关。然而，口服大肠杆菌K1后菌血症的发展并没有因Pila的突变而减少。因此，1型菌毛的丧失与消化道内定植的部位依赖效应相关，而不干扰血流侵袭。
A type 1 pilus-deficient mutant of a systemically invasive Escherichia coli K1 strain was constructed by directed mutagenesis of pilA, the gene that codes for the major structural subunit of type 1 pili. By comparing this mutant with an isogenic pilA+ strain, we were able to assess the role of type 1 piliation in alimentary tract colonization and bloodstream invasion in neonatal rats. Intestinal colonization was not significantly affected by the pilA mutation; in contrast, loss of type 1 piliation correlated with a dramatic decrease in oropharyngeal colonization. Nevertheless, development of bacteremia after oral administration of E. coli K1 was not diminished by the mutation in pilA. Thus, loss of type 1 piliation correlated with a site-dependent effect on colonization within the alimentary tract while not interfering with bloodstream invasion.