Salmonella pathogenicity island 2 influences both systemic salmonellosis and Salmonella-induced enteritis in calves
Salmonella pathogenicity island 2 influences both systemic salmonellosis and Salmonella-induced enteritis in calves
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DOI：
10.1128/iai.69.1.367-377.2001
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发表时间：
2001-01-01
影响因子：
3.1
通讯作者：
Wallis, TS
中科院分区：
文献类型：
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作者：
Bispham, J;Tripathi, BN;Wallis, TS
我们已经使用签名标记突变法来鉴定宿主特异性肠炎沙门氏菌都柏林型的突变株，该突变株在小牛和/或BALB/c小鼠中是无毒的。在沙门氏菌致病性岛2(SPI-2)的ssed基因中发现了一个插入转座子的突变体，该基因编码一个可能的分泌型效应蛋白。该突变体是从牛宿主中恢复的，而不是从感染都柏林突变体库后的小鼠宿主中恢复的。然而，随后证明，在通过静脉或口服途径感染小牛后，接种SSED突变体的纯疫苗可被减毒。SSED突变体对牛肠黏膜具有完全侵袭性，但随后无法在体内增殖到与亲本菌株相同的数量。SSED突变体和第二个SPI-2突变体，在SSAT基因中插入了转座子，诱导了！与亲本品系相比，牛回肠结扎后的分泌和炎症反应明显减弱。这些结果表明，都柏林血清型需要SPI-2来诱导犊牛全身和肠道沙门氏菌病。
We have used signature-tagged mutagenesis to identify mutants of the host-specific Salmonella enterica serotype Dublin which were avirulent in calves and/or BALB/c mice. A mutant with a transposon insertion in the sseD gene of Salmonella pathogenicity island 2 (SPI-2), which encodes a putative secreted effector protein, was identified. This mutant was recovered from the bovine host but not from the murine host following infection with a pool of serotype Dublin mutants. However, a pure inoculum of the sseD mutant was subsequently shown to be attenuated in calves following infection either by the intravenous route or by the oral route. The sseD mutant was fully invasive for bovine intestinal mucosa but was subsequently unable to proliferate to the same numbers as the parental strain in vivo. Both the sseD mutant and a second SPI-2 mutant, with a transposon insertion in the ssaT gene, induced! significantly weaker secretory and inflammatory responses in bovine ligated ileal loops than did the parental strain. These results demonstrate that SPI-2 is required by serotype Dublin for the induction of both systemic and enteric salmonellosis in calves.