多糖合成途径中功能基因的鉴定及其在粘细菌发育中的研究
时间:2018-07-10 10:37 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：粘细菌是一类具有复杂细胞行为的原核生物，在细胞生长、捕食、运动及发育等方面表现出显著的社会性特征，是目前已知的原核生物中唯一具有多细胞行为特征的类群。由于粘细菌特殊的生命特征，被认为是最高等的原核生物，因此其独特的多细胞行为以及复杂的发育调控机制已经被越来越多的研究者所关注。子实体结构的形成以及滑行过程中所呈现的两种不同的运动形式 (A motility, S motility) 是粘细菌显著的行为学特征，其细胞间信号传导和胞外基质在这些过程中起到重要的作用。粘细菌的胞外基质主要是由多糖和部分蛋白组成，前期研究发现粘细菌在生长过程中并不能利用单糖和寡聚糖，推测是通过糖异生途径将氨基酸转化为合成胞外基质所需的单糖。因为鉴于胞外基质在粘细菌发育机制中的重要作用，对粘细菌胞外基质多糖的组成以及多糖合成途径中重要功能基因的研究具有重要的意义。25530 关键词：粘细菌；子实体；冒险运动；社会运动；胞外基质多糖 Identification and developmental research of the polysaccharide synthesis genes from Myxococcus xanthus DK1622 Abstract： Myxobacteria are a group of prokaryotes that display complex multicellular behaviors. Their cell growth, predation, movement and development and other aspects show significantly social characteristics, which is currently known the only prokaryotes with multicellular behavior groups. Due to the characteristics of life special myxobacteria, it is considered as the most advanced prokaryotes. Because of the unique multicellular behavior and complex developmental regulatory mechanisms, it has been concerned by more and more researchers. Two different motility in fruiting body formation and the gliding motility (A motility, S motility) is the characteristic behavior of myxobacteria, in which intercellular signaling and extracellular matrix play an important role. Myxobacterial extracellular matrix is mainly composed of polysaccharides and proteins. The previous study found that bacteria cannot use monosaccharide and oligosaccharides, which presumably generate from amino acid by gluconeogenesis pathway. Given the important role of extracellular matrix in the mechanism of the development of the myxobacteria, it is of great significance to study the composition of extracellular matrix polysaccharides and the important functional genes in the process of the synthesis and metabolism of polysaccharides. Key words: myxobacteria；fruiting body；adventurous motility；social motility；extracellular polysaccharide 目 录 摘要 1 关键词 1 Abstract. 1 Key words 1 引言 2 1 材料方法 3 1.1 菌株和质粒 3 1.2 引物 4 1.3 培养基与试剂 5 1.4 主要仪器 5 1.5 插入失活载体的构建 6 1.5.1 M. xanthus DK1622基因组的提取 7 1.5.2 多糖合成基因同源臂的扩增 7 1.5.3 PCR产物的T/A克隆 7 1.5.4 酶连产物的热激转化 8 1.5.5 质粒的提取 8 1.5.6 质粒的双酶切 8 1.5.7 琼脂糖凝胶DNA回收 8 1.5.8 pBJ113-同源臂载体的构建 8 1.6 粘细菌M. xanthus电转化 9 1.7 菌株插入失活的验证 9 1.7.1 DNA水平的验证 9 1.7.2 RNA水平的验证 9 1.8 序列分析软件与在线分析网址 11 (责任编辑：qin) |