發(fā)布時(shí)間：2018-06-04 23:31

  本文選題：鋅污染 + 多相分類學(xué)　； 參考：《華中農(nóng)業(yè)大學(xué)》2017年碩士論文

【摘要】：為開發(fā)具有重金屬修復(fù)能力的微生物資源,本研究從湖南省臨湘市忠坊鎮(zhèn)鋅污染水稻田中分離了一株具有鋅抗性的細(xì)菌,命名為TBZ30~T,我們發(fā)現(xiàn)該菌株對(duì)Zn~(2+)中有較高抗性(MIC=3mM),并且能夠去除Zn~(2+),降低Zn~(2+)濃度,可能與該菌產(chǎn)生大量的胞外多糖來(lái)吸附Zn~(2+)相關(guān),該特點(diǎn)具有很大的潛在利用價(jià)值。通過(guò)16S rRNA比對(duì)分析,TBZ30~T屬于Mucilaginibacter屬,且與該屬細(xì)菌相似度最高為95.8%,基于16S rRNA的系統(tǒng)發(fā)育進(jìn)化樹分析,TBZ30~T與Mucilaginibacter gynuensis YC7003T、Mucilaginibacter mallensis MP1X4 T、Mucilaginibacter litoreus BR-18 T三個(gè)菌親緣關(guān)系最相近,相似度分別為95.8%、95.4%、95.4%。對(duì)該菌進(jìn)行了進(jìn)一步的多項(xiàng)分類學(xué)分析以及基因組分析,TBZ30~T是一株革蘭氏陰性桿狀細(xì)菌,無(wú)鞭毛,無(wú)運(yùn)動(dòng)性,無(wú)孢子產(chǎn)生。該菌嚴(yán)格好氧生長(zhǎng),生長(zhǎng)過(guò)程中產(chǎn)生粉紅色色素,氧化酶和過(guò)氧化氫酶陽(yáng)性,并且在生長(zhǎng)后期能夠產(chǎn)生大量的胞外多聚物。TBZ30~T含有唯一呼吸醌為MK-7,其主要全細(xì)胞脂肪酸是iso-C15:0和summed feature 3,主要的極性脂類型為磷脂酰乙醇胺、未知的磷脂、未知的氨磷脂、未知的氨脂、未知的脂類、未知的糖脂。TBZ30~T的G+C含量是49%mol。通過(guò)以上多項(xiàng)分類學(xué)鑒定,TBZ30~T屬于Mucilaginibacter的一個(gè)新種,該種命名為Mucilaginibacter pedocola sp.nov,其模式菌株是TBZ30~T�；蚪M草圖測(cè)序以及基因組注釋顯示,其基因組大小為7,035,113 bp,含有3132個(gè)蛋白質(zhì)編碼基因(其中2736個(gè)基因在COG分析中預(yù)測(cè)了相應(yīng)的功能),50個(gè)tRNA編碼基因,14個(gè)rRNA編碼基因以及54個(gè)重金屬抗性相關(guān)的基因,其中與鋅抗性相關(guān)的基因有21個(gè),與胞外多糖相關(guān)的基因有11個(gè),這些基因型特征與TBZ30~T的表型特征相符合,通過(guò)分析TBZ30~T的基因組,使得我們對(duì)Mucilaginibacter有了進(jìn)一步的認(rèn)識(shí),這對(duì)Mucilaginibacter屬的開發(fā)和利用具有深遠(yuǎn)的意義,同樣為鋅的微生物修復(fù)提供了新的思路。
[Abstract]:In order to develop microbial resources with heavy metal remediation ability, a zinc-resistant bacterium was isolated from Zinc-contaminated paddy field in Zhongfang Town, Linxiang City, Hunan Province. Named TBZ30 (TBZ30), we found that the strain had a high resistance to MIC3mMN, and could remove ZnZZ2 and reduce the concentration of ZnO-2), which may be related to the production of a large amount of extracellular polysaccharides (EPS) to adsorb ZnO-2), which has great potential utilization value. TBZ30T belongs to Mucilaginibacter genus by 16s rRNA comparison, and it has the highest similarity to the genus Mucilaginibacter. The phylogenetic tree analysis of TBZ30T based on 16s rRNA and Mucilaginibacter gynuensis YC7003T Mucilaginibacter mallensis MP1X4TMucaginibacter litoreus BR-18T has the most close relationship, and the similarity is 95.8895. 4%. Further taxonomic analysis and genomic analysis of this strain were carried out. TBZ30T was a gram-negative bacilli with no flagellum, motility and spore production. The bacterium strictly aerobic growth, the growth process produced pink pigments, oxidase and catalase positive, And in the later stage of growth, a large number of extracellular polymers. TBZ30T contained only respiratory quinone MK-7. The main fatty acids in the whole cell were iso-C15: 0 and summed feature 3. The main polar lipid types were phosphatidylethanolamine, unknown phospholipid, unknown aminophosphatidylcholine. The G C content of unknown ammonia lipid, unknown lipids, unknown glycolipid. TBZ30 + T was 49 mol. A new species of Mucilaginibacter, Mucilaginibacter pedocola sp. Nov, was identified by taxonomy. Genome sketch sequencing and genome annotation show, Its genome size is 7035113 BP and contains 3132 protein coding genes (2736 of which predicted corresponding functional genes, 50 tRNA coding genes, 14 rRNA coding genes and 54 heavy metal resistance-related genes in COG analysis. There are 21 genes related to zinc resistance and 11 genes related to exopolysaccharide. These genotypes are consistent with the phenotypic characteristics of TBZ30T. By analyzing the genome of TBZ30T, we have a better understanding of Mucilaginibacter. This is of great significance to the development and utilization of Mucilaginibacter, and also provides a new idea for the microbial remediation of zinc.
【學(xué)位授予單位】：華中農(nóng)業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：X172;Q939

【參考文獻(xiàn)】

相關(guān)期刊論文 前6條

1 王革嬌;王倩;陳芳;李t熜，

本文編號(hào)：1979339