【作者】 高冬婷；

【导师】 张利平；

【作者基本信息】 河北大学 ， 微生物学， 2007， 硕士

【摘要】 2,5－二酮基-D-葡萄糖酸途径是合成2-酮基-L-古龙酸(2-keto-L-gulonate,2-KLG)的途径之一,2-酮基-D-葡萄糖酸(2-keto-D-gluconate,2-KDG)是此途径的重要中间代谢物。本实验对2-KDG相对高产菌株DK4和其突变菌株MDK4的代谢途径进行了探索,并对7株野生2-KDG产生菌进行了初步鉴定。通过对菌株DK4和菌株MDK4发酵液成份的分析,将菌株DK4和菌株MDK4合成2-KDG的代谢过程初步归属于2,5-二酮基-D-葡萄糖酸途径。将菌株DK1、DK2、DK3、DK4、DK5、DK6和菌株DK7的16S rDNA序列与GenBank中序列进行比对,结果表明,供试菌株与假单胞菌属的16S rDNA序列相似性最高,均达到98%以上。根据16S rDNA序列的测定结果,7株供试菌的系统发育地位应确定为：细菌域(Bacteria)、变形细菌门(Proteobacteria)、γ-变形菌纲(Gamma-proteobacteria)、假单胞菌目(Pseudomonadales)、假单胞菌科(Pseudomonadaceae)、假单胞菌属(Pseudomonas)。结合形态特征和生理生化特性,初步将菌株DK1和菌株DK5归属于蒙氏假单胞菌(Pseudomonas monteilii)的近似种；将菌株DK2归属于绿真假单胞菌(Pseudomonas chlororaphis)的近似种；将菌株DK3归属于荧光假单胞菌(Pseudomonas fluorescens)的近似种；将菌株DK4、DK6和菌株DK7归属于杰森尼假单胞菌(Pseudomonas jessenii)的近似种。更多还原

【Abstract】 The 2,5-diketo-D-gluconate pathway is one of the microbial approaches for 2-keto-L-gulonate,2-keto-D-gluconate is intermediate product during the 2,5-diketo-D-gluconate pathway. The metabolism pathway of the 2-keto-D-gluconate relative high yield strain DK4 and its mutant stain MDK4 were primarily researched. Seven 2-keto-D-gluconate producing strains were primarily identified to genus or species level.The approaches for 2-keto-D-gluconate of strain DK4 and strain MDK4 would belong to 2,5-diketo-D-gluconate pathway for 2-keto-L-gulonate sysnthesis by analyzing the components of the fermentation broth of strain DK4 and strain MDK4.The 16S rDNA sequences of strain DK1, DK2, DK3, DK4, DK5, DK6 and strain DK7 were determined and compared with the 16S rDNA sequence of all the proteobacteria in GenBank. The similarities between the 7 strains and the closest neighbors of Pseudomonas are over 98%. According to the phylogeny analysis based on the 16S rDNA sequence, the phylogeny status of the 7 strains are primarily identified to Bacteria; Proteobacteria; Gamma-proteobacteria; Pseudomonadales; Pseudomonadaceae; Pseudomonas. Associating with physiological and biochemical characteristics, these strains were primarily identified to species level. Strain DK1 and strain DK5 belong to the approximative species of Pseudomonas monteilii. Strain DK2 belongs to the approximative species of Pseudomonas chloror aphis. Strain DK3 belongs to the approximative species of Pseudomonas fluorescens. Strain DK4, DK6 and strain DK7 belong to the approximative species of Pseudomonas jessenu.更多还原