根据鼠疫耶尔森菌的遗传学特征分析云南玉龙鼠疫疫源地的性质

发布时间：2018-01-29 21:07

本文关键词： 鼠疫耶尔森菌鼠疫自然疫源地序列分析编码序列　出处：《中国疾病预防控制中心》2009年硕士论文　论文类型：学位论文

【摘要】： 鼠疫是由鼠疫耶尔森菌引起的一种危害严重的烈性传染病。鼠疫自然疫源地在世界范围内的分布相当广泛,在时间跨度上也有1500年的历史,生化表型上都非单一群体,同时鼠疫菌的染色体又在不断的发生基因水平上的改变,是一类进化比较活跃的细菌。目前已有近10株鼠疫菌的全基因组已被测序,为进行相关的研究提供了丰富的资料。 2005年,在云南省玉龙县鹿子自然村先后发现高热、咳嗽、咳痰、痰中带血、呼吸困难病人5例,初步诊断为“不明原因重症肺炎”,后确诊为“肺鼠疫”。卫生部及云南省卫生厅决定由云南省地方病防治所、中国疾控中心传染病预防控制所等5个专业技术部门组成联合调查队对玉龙县是否存在着鼠疫疫源地进行自然生态、宿主、媒介、血清学及病原学的系统调查。重点以玉龙县黄山镇鹿子村为中心,向周围的村庄进行放射性调查。调查结果显示,该地区的大绒鼠和齐氏姬鼠是优势鼠种,特新蚤指名亚种、方叶栉眼蚤为主要媒介,指示动物犬和猫血清中鼠疫F1抗体的阳性率分别达到23.5%和26.4%,并且在自毙鼠和蚤中分离到5株鼠疫菌。根据此调查结果,判定了玉龙县存在着鼠疫自然疫源地。我们对此次调查中分离到的鼠疫菌(D106004)提取了DNA,并选择来自滇西山地齐氏姬鼠-大绒鼠疫源地(剑川菌株D182038)和青藏高原喜马拉雅旱獭疫源地(西藏那曲菌株Z176003)的鼠疫菌作为对照菌株,进行了全基因组序列测定和编码序列(CDS)预测。通过对D182038,D106004,CO92,KIM,91001,Nepal516,Antiqua,Pestoides F等8株鼠疫菌基因组上CDS的两两比较,建立了默认编码序列(Default)数据库,在此基础上,对玉龙和剑川鼠疫菌的CDS进行了比较分析。结果显示:剑川菌株和玉龙菌株的CDS在总体COG分类的构成上无明显差别,但在结合其他菌株形成的Default数据库中,可以看到两株鼠疫菌的CDS在COG簇的构成上存在着具体的差别。同时,我们用鼠疫疫苗EV76的高表达蛋白序列与玉龙、剑川鼠疫菌的基因组进行了比较。云南玉龙菌株D106004和剑川菌株D182038的“高表达基因”比较接近,但玉龙菌株和剑川菌株在部分高表达基因上有着具体的差异。在有差别的56条蛋白序列中,玉龙菌株有24条蛋白序列可能被大量表达,剑川菌株有16条蛋白序列可能被大量表达。这些均提示,玉龙和剑川鼠疫菌在高表达基因上有一定的差异,这些差异可能是玉龙和剑川菌株在进化过程中独自进化造成的。通过对玉龙与剑川鼠疫菌CDS和高表达蛋白序列遗传学特征的比较,发现它们可能来自于同一个祖先,但是在进化过程中两者又各自有独特的特征。玉龙与剑川鼠疫自然疫源地属于同一种类型,但又相对独立活动的鼠疫自然疫源地,这种独立性是由于两片疫源地在地理上的阻隔形成的。且这种独立性的存在已经相当久远,因而表现为鼠疫菌株间多位点的差异。
[Abstract]:Yersinia pestis is a severe infectious disease caused by Yersinia pestis. Plague natural foci are widely distributed in the world and have a history of 1500 in the time span. Biochemical phenotype is not a single population, at the same time, Yersinia pestis chromosomes are constantly occurring gene level changes. The whole genome of nearly 10 strains of Yersinia pestis has been sequenced. In 2005, 5 patients with high fever, cough, expectoration, blood in sputum and dyspnea were found in Luzi Natural Village, Yulong County, Yunnan Province. Later diagnosed as "pneumonic plague." The Ministry of Health and the Department of Health of Yunnan Province decided by the Yunnan Provincial endemic Disease Prevention and Control Institute. Five professional and technical departments such as the Institute of Infectious Diseases Prevention and Control of the China Center for Disease Control and Prevention formed a joint investigation team to conduct natural ecology, host and media for the existence of plague foci in Yulong County. The systematic investigation of serology and etiology was carried out, focusing on Luzi Village, Huangshan Town, Yulong County, and radioactivity investigation was carried out to the surrounding villages. The results showed that Apodemus chrysoides and Apodemus chizyzae were the dominant species in this area. The positive rates of Yersinia pestis F1 antibody in the sera of dogs and cats were 23.5% and 26.4% respectively. Five strains of Yersinia pestis were isolated from dead rats and fleas. We extracted DNA from Yersinia pestis D106004 isolated in this investigation. The foci of Apodemus chrysodii (strain D182038) and Himalayan marmot (strain Z176003) were selected from western Yunnan mountainous region. Of Yersinia pestis as a control strain. The whole genome sequencing and coding sequence prediction were carried out. The antiqua of D182038 / D106004 / KIMM 91001 / Nepal516 was studied. Based on the pairwise comparison of CDS on the genome of 8 strains of Yersinia pestis, Pestoides F, a default coding sequence (Default) database was established. The CDS of Yulong and Jianchuan Yersinia pestis were compared and analyzed. The results showed that there was no significant difference in the composition of the total COG classification between the CDS of Jianchuan strain and that of Yulong strain. However, in the Default database combined with other strains, it can be seen that the CDS of the two strains of Yersinia pestis has a specific difference in the composition of COG cluster. At the same time, we used the Yersinia pestis vaccine EV76 high expression protein sequence and Yulong. The genomes of Yersinia pestis in Jianchuan were compared. The "high expression genes" of Yulong strain D106004 and strain D182038 were similar. However, there were specific differences between Yulong strain and Jianchuan strain on some high expression genes. Among the 56 protein sequences, 24 protein sequences of Yulong strain could be expressed in large quantities. The 16 protein sequences of Jianchuan strain may be expressed in a large amount, which suggests that Yulong and Yersinia pestis have some differences in high expression genes. These differences may be caused by the evolution of Yulong and Jianchuan strains alone. By comparing the genetic characteristics of Yulong and Yersinia pestis CDS and high expression protein sequences, it was found that they may have originated from the same ancestor. Yulong and Jianchuan plague natural foci belong to the same type, but relatively independent activities of plague natural foci. This independence is due to the geographical barrier between the two foci, and this independence has existed for a long time, thus showing the difference of multiple loci between the strains of Yersinia pestis (Yersinia pestis).
【学位授予单位】：中国疾病预防控制中心
【学位级别】：硕士
【学位授予年份】：2009
【分类号】：R181.3

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