本文選題：齲病 + 全基因組測序��； 參考：《吉林大學(xué)》2014年碩士論文

【摘要】：目的： 齲病是一種以細(xì)菌為主的多因素作用下發(fā)生在牙體硬組織中的慢性進(jìn)行性破壞性疾病，是口腔中兩大常見疾病之一，病理表現(xiàn)為無機(jī)物的脫礦和有機(jī)物的分解。齲病是一種多因素性疾病，其中細(xì)菌是齲病的主要病原菌，僅有變形鏈球菌的存在和人類齲病是一致相關(guān)聯(lián)的。另外，研究報(bào)道齲病是大多數(shù)人在一生中相關(guān)的最昂貴的感染。近些年氟化物已廣泛應(yīng)用于臨床防齲，但長期使用大量氟化物防齲可能會導(dǎo)致耐氟菌株的出現(xiàn)，并且有學(xué)者在體外已成功誘導(dǎo)出變形鏈球菌耐氟菌株。有研究證實(shí)變形鏈球菌耐氟菌株比親代菌株有更強(qiáng)的致齲能力。學(xué)者僅限于對耐氟菌株耐酸相關(guān)基因ffh、dgk、dltC、ccpA等進(jìn)行了基因突變檢測。但對于耐氟菌株其他毒力因子突變的情況，目前還不清楚，尚需進(jìn)一步研究。目前對于變形鏈球菌UA159全基因組測序已經(jīng)完成，并獲得登錄號AE014133。從分子水平上對變形鏈球菌耐氟菌株全基因組進(jìn)行測序，確定基因突變位點(diǎn)及編碼蛋白質(zhì)突變意義，既可以為氟化物的應(yīng)用防齲打下基礎(chǔ)，又能夠更進(jìn)一步了解耐氟致齲機(jī)制。為今后齲病預(yù)防藥物的研發(fā)以及篩選抗齲藥物提供一定的理論及實(shí)驗(yàn)基礎(chǔ)。 方法： 1.變形鏈球菌耐氟菌株UA159-FR的篩選與鑒定。 2.變形鏈球菌耐氟菌株全基因組的提取。 3.利用Illumina Hiseq2000和PACBIO RS測序技術(shù)完成該菌株的基因組完成圖測序，，分別構(gòu)建了Illumina Hiseq2000PE文庫（300~500bp）、MP文庫（3kb）和PacBio文庫（8~10kb），對獲得的測序數(shù)據(jù)進(jìn)行質(zhì)控后利用生物信息學(xué)分析手段完成該菌株的全基因組測序及基因組完成圖繪制。 4.將變形鏈球菌耐氟菌株UA159-FR與參考菌UA159比對后進(jìn)行生物信息學(xué)分析。 結(jié)果： 1.鑒定了實(shí)驗(yàn)中培養(yǎng)的細(xì)菌確為變形鏈球菌耐氟菌株UA159-FR。 2.完成了變形鏈球菌耐氟菌株全基因組測序，并根據(jù)生物學(xué)信息完成了該細(xì)菌全基因組完成圖繪制。 3.從基因組水平上對參照細(xì)菌、測序細(xì)菌在內(nèi)的5株細(xì)菌構(gòu)建了系統(tǒng)進(jìn)化發(fā)育樹。 4．將S.mutans UA159-FR中的1878個(gè)基因與S.mutans UA159通過blastn比對，發(fā)現(xiàn)有20個(gè)基因發(fā)生突變，其中orf00385、orf00876、orf01053、orf1135、orf01258屬于同義突變；其中orf00091、orf00875、orf00929、orf00986、orf01042、orf01092、orf01190、orf01600屬于錯義突變；其中orf01786屬于移碼突變；orf00032、orf00544、orf00585、orf01127、orf01130、orf01759屬于終止密碼突變。與變形鏈球菌粘附有關(guān)的基因（2種）：orf00875（glucosyltransferase-I）葡萄糖基轉(zhuǎn)移酶I、orf00876（glucosyltransferase-Si）葡萄糖基轉(zhuǎn)移酶Si；與變形鏈球菌產(chǎn)酸有關(guān)的基因有2種）orf00585（citrate synthase）檸檬酸合成酶；orf01092（enolase）烯醇酶。 5.5個(gè)基因間隔區(qū)發(fā)生了堿基替換和插入。 6.變形鏈球菌耐氟菌株基因組已經(jīng)提交Genbank，并獲得基因組登陸號：CP007016. 結(jié)論： 成功完成了變形鏈球菌耐氟菌株UA159-FR全基因組測序，并確定了基因及基因間區(qū)突變位點(diǎn)，確定了基因突變意義，為進(jìn)一步研究蛋白質(zhì)結(jié)構(gòu)與功能的突變提供一定的理論基礎(chǔ)。同時(shí)推測變形鏈球菌耐氟菌株致齲性增強(qiáng)可能與耐酸相關(guān)操縱子和基因組水平上的甲基化有一定關(guān)系。這為今后齲病預(yù)防藥物的研發(fā)以及篩選抗齲藥物提供一定的理論及實(shí)驗(yàn)基礎(chǔ)。
[Abstract]:Objective:
Caries, a chronic, progressive and destructive disease occurring in the hard tissue of teeth, is one of the two common diseases in the tooth. It is one of the most common diseases in the mouth. The pathology shows the demineralization of inorganic substances and the decomposition of organic matter. Caries is a multi factor disease. The bacterium is the main pathogen of caries and only Streptococcus mutans The presence of human caries is associated with human caries. In addition, it is reported that caries are the most expensive infections associated with most people in their lives. In recent years fluorides have been widely used in clinical caries prevention, but long term fluoride prevention may lead to the emergence of fluoride resistant strains, and some scholars have successfully induced deformable chains in vitro. Some studies have confirmed that the fluorine resistant strain of Streptococcus mutans has a stronger cariogenic ability than the parent strain. Scholars have only limited the mutation detection of the acid resistant gene FFH, dgk, dltC and ccpA of the fluorine resistant strains, but the situation of the mutation of other virulence factors of the fluorine resistant strains is not yet clear, and it is still needed to be further studied. The whole genome sequencing of Streptococcus mutans UA159 has been completed, and the login number AE014133. is obtained from the molecular level to sequence the whole genome of Streptococcus mutans to determine the mutation site and the significance of the mutation of the encoded protein. It can not only provide a basis for the application of fluoride to prevent dental caries, but also further understand the fluorine resistance. Caries mechanism provides a theoretical and experimental basis for the future research and development of dental caries preventive agents and screening of anti caries drugs.
Method錛

本文編號：1982213