【摘要】：豬鏈球菌(Streptococcus suis,SS)是一種重要的人畜共患病病原,能導(dǎo)致仔豬患腦膜炎、敗血癥、關(guān)節(jié)炎、心內(nèi)膜炎、肺炎和人的腦膜炎。豬鏈球菌2型流行最廣,對(duì)豬的致病力也最強(qiáng),給養(yǎng)豬業(yè)造成了巨大的經(jīng)濟(jì)損失,在公共衛(wèi)生方面,也對(duì)相關(guān)從業(yè)人員的生命安全構(gòu)成了威脅。更為嚴(yán)重的是,當(dāng)豬鏈球菌形成生物被膜時(shí),生物被膜會(huì)為細(xì)菌提供一種保護(hù)性生活方式,可能會(huì)大大提高其抗逆性和致病性。本文研究了豬鏈球菌生物被膜的生物學(xué)特性,發(fā)現(xiàn)大部分豬鏈球菌均具有不同程度形成生物被膜的能力,其中10株(10/32)具備較強(qiáng)的生物被膜形成能力,豬鏈球菌生物被膜的成熟約需60 h,培養(yǎng)基中葡萄糖濃度是影響生物被膜形成的重要因素。胞外多糖是生物被膜的重要組成部分,多糖測(cè)定結(jié)果顯示生物被膜中的多糖含量顯著高于浮游菌。氨芐青霉素鈉和阿莫西林對(duì)5株(5/10)豬鏈球菌生物被膜的最低抑菌濃度(MIC)和最低殺菌濃度(MBC)均高于浮游菌約2500倍。掃描電鏡觀(guān)察發(fā)現(xiàn),生物被膜內(nèi)豬鏈球菌彼此粘連,形成致密的三維立體結(jié)構(gòu)。分別用抗生素、噬菌體SMP和裂解酶LySMP處理生物被膜,結(jié)果顯示:正常劑量抗生素(20μg/ml)對(duì)生物被膜結(jié)構(gòu)的破壞作用和對(duì)被膜菌的殺滅作用均不明顯;噬菌體SMP既不能有效殺滅被膜菌也不能有效破壞生物被膜結(jié)構(gòu);裂解酶LySMP可以在12 h以?xún)?nèi)殺滅幾乎所有的SS2-4和SS2-H生物被膜菌,并清除它們80%以上的生物被膜。對(duì)豬鏈球菌生物被膜生物學(xué)特性及降解方法的研究可為進(jìn)一步揭示生物被膜的形成機(jī)制、耐藥機(jī)理,以及清除生物被膜等提供理論依據(jù)。
[Abstract]:Streptococcus suis (Streptococcus suis,SS) is an important zoonotic pathogen that causes meningitis septicemia arthritis endocarditis pneumonia and human meningitis in piglets. Streptococcus suis type 2 has the most widespread prevalence and the strongest virulence to pigs, which has caused huge economic losses to pig industry. In public health, it also poses a threat to the life safety of relevant employees. More seriously, when Streptococcus suis forms biofilm, biofilm will provide a protective lifestyle for bacteria, which may greatly improve its resistance and pathogenicity. The biological characteristics of Streptococcus suis biofilm were studied in this paper. It was found that most Streptococcus suis had the ability to form biofilm in varying degrees, among which 10 strains (10 渭 32) had strong biofilm forming ability. It takes about 60 hours to mature the biofilm of Streptococcus suis. Glucose concentration in the culture medium is an important factor influencing the formation of biofilm. Exopolysaccharide is an important part of biofilm. The content of polysaccharide in biofilm is significantly higher than that of P. aeruginosa. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of ampicillin sodium and amoxicillin on the biofilm of Streptococcus suis were 2500 times higher than those of S. suis. Scanning electron microscopy (SEM) showed that Streptococcus suis adhered to each other in the biofilm and formed a dense three-dimensional structure. The biofilm was treated with antibiotics, bacteriophage SMP and lyase LySMP, respectively. The results showed that the normal dose of antibiotics (20 渭 g / ml) did not destroy the biofilm structure and kill the biofilm bacteria. Bacteriophage SMP could not kill the biofilm bacteria or destroy the biofilm structure effectively, and the lyase LySMP could kill almost all SS2-4 and SS2-H biofilm bacteria within 12 h, and eliminate more than 80% of the biofilm. The study on the biological characteristics and degradation methods of Streptococcus suis biofilm can provide a theoretical basis for further revealing the mechanism of biofilm formation, drug resistance mechanism, and removal of biofilm from Streptococcus suis.
【學(xué)位授予單位】：上海交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2011
【分類(lèi)號(hào)】：R378

【引證文獻(xiàn)】

相關(guān)期刊論文 前1條

1 張瑞安;劉軍;馮書(shū)章;;噬菌體裂解酶的研究進(jìn)展[J];中國(guó)生物制品學(xué)雜志;2012年05期

相關(guān)碩士學(xué)位論文 前2條

1 卜倩倩;鹽酸小檗堿通過(guò)SortaseA和Esp途徑影響糞腸球菌生物被膜的初步探討[D];中南大學(xué);2012年

2 劉靜;大環(huán)內(nèi)酯類(lèi)及β-內(nèi)酰胺類(lèi)藥物對(duì)豬鏈球菌生物被膜的體外作用研究[D];東北農(nóng)業(yè)大學(xué);2012年

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本文編號(hào)：2465680