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木质素降解菌CY的分离鉴定及其生长特性研究

时间:2020-06-17 20:13来源:毕业论文
从连云港新鲜海水中分离筛选到一株对木质素具有降解作用的菌株CY。CY在 30°C、250 r/min 条件下对木质素的降解率为42.31%,通过对菌落观察、革兰氏染色、电镜等手段,对其进行了形态

摘要  本文从连云港新鲜海水中分离筛选到一株对木质素具有降解作用的菌株CY。CY在  30°C、250 r/min 条件下对木质素的降解率为42.31%,通过对菌落观察、革兰氏染色、电镜等手段,对其进行了形态观察,通过血清学实验,对该菌株进行了生理生化鉴定;通过对其基因组序列进行  PCR  扩增和 16SrDNA测序,与EzBioCloud网站中中收录的与其同源性较高的菌株进行了系统发育分析并通过MAGE 5.1邻接法(Neighborhood-joining)进行关系分析和系统进化树的构建。此外,对其生长特性也进行了研究。实验结果表明,菌株  CY 革兰氏染色为红色,为阴性菌,球状,无鞭毛,直径约为0.84 µm,在海水固体营养平板上形成的菌落特征为菌落呈乳黄色,边缘光滑、隆起、圆形、粘稠、易挑取;菌株 CY 的  16S rDNA 序列与  GenBank  基因库中海粘假交替单胞菌(Pseudoalteromonas mariniglutinosa)的 16S rDNA  序列有  97%~99%的同源性。菌株CY与海粘假交替单胞菌 KMM 3635T (登录号: AJ507251)的亲缘关系最近,达到97.16%。结合传统的生理生化特性鉴定以及  16S rDNA序列分析的结果,判定菌株 CY 为海粘假交替单胞菌(Pseudoalteromonas  mariniglutinosa),在 Genbank 上的序列注册号为: KT717632。 此外, 菌株CY在  30°C、   250 r/min  条件下摇床振荡培养的生长曲线为,0 h~4 h 为生长延滞期,4 h~60 h  为对数生长期,60 h~75 h 为稳定期,80 h以后为衰亡期。该菌株的最适生长  pH 为  7,最适生长温度为  30°C,最适盐浓度为 20 g/L。 该论文有图 9幅,表2个,51078
参考文献 20篇。  毕业论文关键词:木质素  海粘假交替单胞菌  分离  鉴定  生长特性
Isolation, identification and growth characteristics of a lignin degrading strain CY  Abstract  This thesis reported the isolation and characterization of a bacterial stain named CY that has the ability to use  lignin  as sole carbon source for growth from the Lianyungang fresh seawater. Up to 42.31 % of 50 mg/L lignin was degraded by this bacterial  under the condition of  30°C,  250 r/min  within.  By  the colony of Gram staining observation,  electron microscopy,  and its morphological observation by serological test,  physiological and biochemical identification.  On the basis of the results of the PCR amplification and 16SrDNA sequencing of its genome sequence, and EzBioCloud site included with high homology strains were phylogenetic analysis and by MAGE 5.1 method (Neighborhood-joining) to construct adjacency relation analysis and phylogenetic tree. In addition,  the growth characteristics was studied. Experimental results showed  that, the strain CY  cells are gramstaining-  negative, non-flagellated. They are globular, 0.84 µm in diameter. After 2 days of incubation on seawater solid nutrient agar,  colonies grew to  milky yellow,  smooth edge,  uplift, round,  thick,  easy picking.  strain CY 16S rDNA sequences and GenBank database sea sticky false alternating the 16S rDNA sequence of Aeromonas  (Pseudoalteromonas mariniglutinosa) 97% - 99% homology. The genetic relationship between the strain CY and 3635T KMM (accession No.: AJ507251) was close, which reached 97.16%.  Based on  physiological characterization,  biochemical  test  and  a partial analysis of the 16S rDNA gene sequence, the bacteria strain CY was identified as  Pseudoalteromonas mariniglutinosa  which  in GenBank sequence number  is   KT717632. When strain CY are  under the conditions of 30°C  250  r/ min  shaking culture growth curve, 0 h~ 4 h is the growth lag phase,4 h~60 h is logarithmic phase, 60 h~75  h  is  stable period  and  80 h  is  the later period of decline. The growth  optimum pH and temperature are 7 and 30°C, the optimum NaCl concentration is 20 g / L.  木质素降解菌CY的分离鉴定及其生长特性研究:http://www.751com.cn/shengwu/lunwen_54590.html
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