摘要能够降解污染基质中的农药且对环境有益的方法之一是生物修复。本文目标是寻找能够降解除草剂均三嗪农药的降解菌。从长期含有均三嗪农药的农田土壤中取样，通过驯化、富集培养等方法，分离筛选出一株能降解均三嗪农药的菌株W1，在LB固体培养基上该降解菌的菌体呈黄色，菌落圆形，边缘整齐规则，表面光滑，中间轻微隆起，易挑取。革兰氏染色呈紫色，为阳性，杆状，无芽孢。通过对W1菌株进行初步探究发现该菌株生长的最适NaCl浓度，pH和通气量分别为1%，7.0 和150mL。研究其生理生化特征发现W1能够利用甘露醇、纤维二糖、乳糖、葡萄糖、蔗糖、果糖和山梨醇七种糖，但不能利用维生素B1，挑取该菌株的单菌落制备成菌悬液并进行16S rDNA PCR扩增和测序，并利用EzBioCloud序列检索，发现W1 菌与Lysinibacillus fusiformis(AB271743)、Lysinibacillus sphaericus (AUOZ0 1000024) 和Lysinibacillus pakistanensis (AB558495)同源性较高，再结合其形态学及生理生化实验鉴定结果，初步判断W1菌为梭形杆菌属(Lysinibacillus sp)。70724

毕业论文关键词：降解菌  均三嗪  分离和筛选  16S rDNA

Isolation, Identification and Growth Characteristics of a s-triazine degrading strain W1 

Abstract Microbial activity has been deemed to be the most influential and significant cause of organophosphorus pesticide removal and biotransformation. This research was to isolate the bacteria that can use s-triazine as sole carbon source.  An efficient s-triazine degrading bacterial strain named as W1 was isolated by continuous enrichment screened from long triazine-treated soils. After 2 days of incubation on LB solid medium. The degrading bacteria in colonies are yellowish, round, circular with entire edges, smooth, convex, easy to pick up. W1 cells are gram-staining-positive, rods, no spore. On the basis of the preliminary inquiry of strain W1, we found that the growth of the optimal concentration of NaCl, pH and ventilation were 1%, 7.0 and 150 ml respectively. To study the physiological and biochemical characteristics showed that stain W1 can utilize mannitol, cellobiose, lactose, glucose, sucrose, fructose and sorbitol, but it can't utilize vitamin B1.Based on 16S rDNA PCR amplification and sequencing, retrieve and use EzBioCloud sequences, strain W1 showed high similarities to  Lysinibacillus fusiformis (AB271743), Lysinibacillus sphaericus AUOZ0 (1000024) and Lysinibacillus pakistanensis (AB558495) . Therefore, we indentified stain W1 is a species in Lysinibacillus sp. 

Key words: Degradation bacteria  Triazine    Isolation and screening  16S rDNA

目录

摘要 I

Abstract II

目录 III

图清单 IV

表清单 IV

绪论 1

1 材料与方法 1

1.1 土壤样本来源 2

1.2 农药及试剂 2

1.3 培养基 2

1.4 降解菌的驯化，富集培养和筛选 2

1.5 降解菌的形态与生理生化鉴定 2

1.6 降解菌的16S rDNA序列的测定 3

2 结果与分析 3

2.1 降解菌的分离与筛选 3

2.2 降解菌的形态鉴定 4

2.3 降解菌的生理生化特征测定