适应性进化及环境因素对马铃薯病原噬菌体在储存和应用中活性的研究

发布时间：2021-02-16 19:17

　　噬菌体已被开发为许多植物病原菌有效的生物控制剂并且成为控制系统性疾病感染方法的一部分。噬菌体具有无毒特性、对宿主细菌的特异性、自我复制、克服细菌耐药性的能力和易于生产等优点,而且噬菌体在生态系统中无处不在,并且含量丰富,因此对噬菌体的分离是相对较为容易。噬菌体鸡尾酒疗法通常被用来控制不同植物病菌的感染,同时也能预防耐药菌的产生。基于以上特点,噬菌体被认为是很有前景的生物控制剂,然而在非低温的保存环境下,其储存稳定性仍然是一个重大挑战然,但是活性噬菌体在土壤中的密度又对其应用的效率是非常关键的。因此,本研究的目的是利用高温环境的适应性进化方式来筛选贮藏过程中活性稳定的噬菌体,并评价与马铃薯植株相关噬菌体混合物在不同环境中的生存能力。本研究第一部分通过高温实验,研究了3种不同马铃薯病原菌的噬菌体（Wc4,CX5,PPSG-11）的进化过程。噬菌体经过60°C处理并通过双层琼脂平板筛选活性更稳定的子代噬菌体,如此进行5个处理循环后的进化噬菌体和未进化的噬菌体在37°C保存60天后,并对他们的稳定性进行评估。结果表明,在60°C热处理后,祖先噬菌体（未进化的噬菌体）的滴度下降了3.30

【文章来源】：中国科学院大学(中国科学院武汉病毒研究所)湖北省

【文章页数】：70 页

【学位级别】：硕士

【文章目录】：
摘要
Abstract
1.0 CHAPTER ONE
    1.1 INTRODUCTION
    1.2 Literature Review
        1.2.1 Bacteriophages
        1.2.2 The structure of Bacteriophages
        1.2.3 Phage classification
        1.2.4 Mechanism of phage propagation
        1.2.5 Bacteriophage control of phytobacteria
        1.2.6 Phage Cocktails
        1.2.7 Phage stability and factors to consider in the application of phages as BCA
        1.2.8 Phage stabilization
        1.2.9 Adaptive phage evolution
    1.3 Problem statement
    1.4 Justification
    1.5 Objectives
2.0 CHAPTER TWO Effects of adaptive evolution on viabilities of bacteriophages against potato bacterial diseasesduring storage
    2.1 Materials and Methods
        2.1.0 Bacterial strains, phages and culture conditions
        2.1.1 Selection of evolution conditions
        2.1.2 Phage Evolution
        2.1.3 Comparison of phage stability
        2.1.4 Determination of the host range and lytic curve pattern of the phages
        2.1.5 Statistical analysis
    2.2 Results
        2.2.1 Selection of evolution conditions
        2.2.2 Phage Evolution
        2.2.3 Comparison of phage stability
            2.2.3.1 Stability of the ancestral and evolved phages at 60°C
            2.2.3.2 Stability of the ancestral and evolved phages at 37° C
        2.2.4 Determination of the host range and lytic curve pattern
    2.3 Discussion
3.0 CHAPTER THREE THE VIABILITY OF A PHAGE COCKTAIL IN POTATO-ASSOCIATEDENVIRONMENT
    3.1 Materials and Methods
        3.1.1 Phage amplification and titering
        3.1.2 Phage cocktail formulation
4 effect on the phage cocktail">        3.1.3 CuSO₄ effect on the phage cocktail
        3.1.4 Survival of the phage cocktail in ultraviolet light
        3.1.5 Persistence of the phage cocktail on potato surface
    3.2 Results
        3.2.1 Phage cocktail formulation
        3.2.2 Cu SO4 effect on the phage cocktail
        3.2.3 Survival of phage cocktail in ultraviolet light
        3.2.4 Persistence of the phage cocktail on potato surface
    3.3 Discussion
4.0 CHAPTER FOUR CONCLUSIONS AND FUTURE PROSPECTS
REFERENCES
ACKNOWLEDGEMENT
APPENDICES
RéSUMé
PUBLICATIONS


【参考文献】：
期刊论文
[1]Bacteriophages Isolated in China for the Control of Pectobacterium carotovorum Causing Potato Soft Rot in Kenya[J]. Peter Muturi,Junping Yu,Alice Nyambura Maina,Samuel Kariuki,Francis B.Mwaura,Hongping Wei.  Virologica Sinica. 2019(03)



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