Investigating the role of small, acid-soluble spore proteins (SASPs) in the resistance of Clostridium perfringens spores to heat.
Investigating the role of small, acid-soluble spore proteins (SASPs) in the resistance of Clostridium perfringens spores to heat.
复制标题
研究小酸溶性孢子蛋白（SASP）在裂孔孢子孢子对热的耐药性中的作用。
DOI：
10.1186/1471-2180-6-50
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发表时间：
2006-06-08
期刊：
影响因子：
4.2
通讯作者：
Sarker, Mahfuzur R.
中科院分区：
文献类型：
--
作者：
Raju, Deepa;Waters, Michael;Setlow, Peter;Sarker, Mahfuzur R.
A型产气荚膜梭菌食物中毒是由产肠毒素的A型产气荚膜梭菌菌株引起的，这些菌株通常具有较高的孢子耐热性。产气荚膜梭菌孢子耐热性的分子基础尚不清楚。在本研究中，我们研究了酸溶小孢子蛋白(SASPs)在产气荚膜梭菌食物中毒分离株产生的孢子耐热性中的作用。我们目前的研究证明，在所调查的五株产气荚膜梭菌临床食物中毒分离株中，所有三个SASP编码基因(ssp1、2和3)都存在。β-GLucuronidase分析表明，这些SSP基因在孢子形成过程中特异表达。与这些表达结果一致，我们的研究还证实了产气荚膜梭菌食物中毒分离株产生SASPs。将产气荚膜梭菌SSP3基因敲除突变体产生的孢子的热敏性与野生型菌株的孢子进行比较，发现SSP3突变体的孢子在100℃时的十进制数折减值(D值)低于野生型菌株的孢子。通过用携带野生型SSP3的重组质粒来补充SSP3突变体的这种效应，表明观察到野生型和SSP3突变体孢子之间D值的差异是由于SSP3的特异性失活。此外，我们的DNA保护实验表明，产气荚膜梭菌能够保护DNA免受DNase I的消化。本研究的结果为产气荚膜梭菌食物中毒分离株产生的SASP具有保护其孢子免受热损伤的作用提供了证据，从食品安全的角度来看，这是非常重要的。进一步深入研究产气荚膜梭菌SASP的作用机制，将有助于理解产气荚膜梭菌保护芽胞免受热损伤的机制。
Clostridium perfringens type A food poisoning is caused by enterotoxigenic C. perfringens type A isolates that typically possess high spore heat-resistance. The molecular basis for C. perfringens spore heat-resistance remains unknown. In the current study, we investigated the role of small, acid-soluble spore proteins (SASPs) in heat-resistance of spores produced by C. perfringens food poisoning isolates. Our current study demonstrated the presence of all three SASP-encoding genes (ssp1, 2 and 3) in five surveyed C. perfringens clinical food poisoning isolates. β-Glucuronidase assay showed that these ssp genes are expressed specifically during sporulation. Consistent with these expression results, our study also demonstrated the production of SASPs by C. perfringens food poisoning isolates. When the heat sensitivities of spores produced by a ssp3 knock-out mutant of a C. perfringens food poisoning isolate was compared with that of spores of the wild-type strain, spores of the ssp3 mutant were found to exhibit a lower decimal reduction value (D value) at 100°C than exhibited by the spores of wild-type strain. This effect was restored by complementing the ssp3 mutant with a recombinant plasmid carrying wild-type ssp3, suggesting that the observed differences in D values between spores of wild-type versus ssp3 mutant was due to the specific inactivation of ssp3. Furthermore, our DNA protection assay demonstrated that C. perfringens SASPs can protect DNA from DNase I digestion. The results from our current study provide evidences that SASPs produced by C. perfringens food poisoning isolates play a role in protecting their spores from heat-damage, which is highly significant and relevant from a food safety perspective. Further detailed studies on mechanism of action of SASPs from C. perfringens should help in understanding the mechanism of protection of C. perfringens spores from heat-damage.
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影响因子：
3.1
作者：
Czeczulin, JR;Collie, RE;McClane, BA
通讯作者：
McClane, BA
影响因子：
3.2
作者：
MASON, JM;SETLOW, P
通讯作者：
SETLOW, P
影响因子：
2.3
作者：
Collie, RE;Kokai-Kun, JF;McClane, BA
通讯作者：
McClane, BA
影响因子：
3.2
作者：
FAIRHEAD, H;SETLOW, B;SETLOW, P
通讯作者：
SETLOW, P
影响因子：
2.1
作者：
Huang, IH;Waters, M;Sarker, MR
通讯作者：
Sarker, MR