Abstract：
:Shigella flexneri causes bacillary dysentery in humans. Essential to the establishment of the disease is the invasion of the colonic epithelial cells. Here we investigated the role of the lipopolysaccharide (LPS) O antigen in the ability of S. flexneri to adhere to and invade polarized Caco-2 cells. The S. flexneri 2a O antigen has two preferred chain lengths: a short O antigen (S-OAg) regulated by the WzzB protein and a very long O antigen (VL-OAg) regulated by Wzz pHS2. Mutants with defined deletions of the genes required for O-antigen assembly and polymerization were constructed and assayed for their abilities to adhere to and enter cultured epithelial cells. The results show that both VL- and S-OAg are required for invasion through the basolateral cell membrane. In contrast, the absence of O antigen does not impair adhesion. Purified LPS does not act as a competitor for the invasion of Caco-2 cells by the wild-type strain, suggesting that LPS is not directly involved in the internalization process by epithelial cells.
journal_name
Biol Resjournal_title
Biological researchauthors
Hoare A,Bravo D,Martinić M,Valvano MA,Contreras I,Álvarez SAdoi
10.4067/S0716-97602012000100003subject
Has Abstractpub_date
2012-01-01 00:00:00pages
21-6issue
1eissn
0716-9760issn
0717-6287pii
S0716-97602012000100003journal_volume
45pub_type
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journal_title：Biological research
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