Virulence mechanisms of plant pathogenic Streptomyces species

马铃薯疮痂病是一种重要的植物病害，在加拿大许多马铃薯种植区都有发生。该疾病的特征是在马铃薯块茎表面上形成表面或凸起的软木样病变。这些病变影响马铃薯作物的适销性，导致马铃薯种植者的重大经济损失。2002年，加拿大马铃薯疮痂病的总经济损失估计在1500 - 1700万美元之间，突出了这种疾病对加拿大马铃薯产业和整个经济的重要性。 常见疥疮的病原体是一种名为疥疮链霉菌的土壤丝状细菌。由这种生物体引起的疾病症状主要是由于产生一种称为thaxtomin A的植物毒素，其功能是纤维素合成抑制剂。此外，其他已知的或推定的毒力决定因素已被确定，被认为有助于由S引起的疾病症状的严重性。疥疮 本研究的短期目标是表征一个新发现的次级代谢产物生物合成簇的产物，该簇对S.疥疮将从S中纯化代谢产物。疥疮培养，以便确定其结构，并评估其对疾病症状发展的贡献。此外，该代谢产物的生物合成将通过构建S.疥疮基因缺失本研究结果将为深入了解沙门氏菌致病性的分子机制提供重要依据。疥疮，这是这项研究的长期目标。预计获得的信息将导致更好地了解农业环境中的疮痂病发展，并可能提出更有效的控制方法和病原体引起it. In此外，这项研究将有利于加拿大通过培训学生的技术，使他们能够在学术机构或政府或工业实验室追求成功的研究事业。

Potato common scab is an important plant disease that occurs in many potato growing regions in Canada. The disease is characterized by superficial or raised corky-like lesions that form on the surface of the potato tuber. These lesions affect the marketability of the potato crop leading to significant economic losses for potato growers. In 2002, the total economic loss to potato scab in Canada was estimated to be between $15-17 million dollars, highlighting the importance of this disease to the Canadian potato industry and the economy as a whole. A causative agent of common scab is a soil-dwelling, filamentous bacterium called Streptomyces scabies. The disease symptoms induced by this organism are mainly due to production of a phytotoxin called thaxtomin A, which functions as a cellulose synthesis inhibitor. In addition, other known or putative virulence determinants have been identified that are thought to contribute to the severity of disease symptoms caused by S. scabies. The short-term goal of this research is to characterize the product of a newly-discovered secondary metabolite biosynthetic cluster that is important for virulence in S. scabies. The metabolite will be purified from S. scabies cultures so that its structure can be determined and its contribution to disease symptom development can be assessed. In addition, the biosynthesis of this metabolite will be examined through construction of S. scabies gene deletions. The results of this study will provide important insight into the molecular mechanisms of pathogenicity in S. scabies, which is the long-term goal of this research. It is anticipated that the information gained will lead to a better understanding of scab disease development in agricultural settings and may suggest more effective ways of controlling it and the pathogens that cause it. In addition, this research will benefit Canada by training students in techniques that will allow them to pursue successful research careers at academic institutions or in government or industry labs.