本文探讨了将重点实验室科研成果转化为课堂教学资源的实例。通过将自主科研成果引入到课堂教学中，使学生们直接了解身边的科学成果和科学研究过程，增加感性材料，化解了教学难点，激发了学生的求知欲，增强了学生的创新意识，显著提高了教学质量。

本文构建了以培养思维和创新能力为主导的整体优化的生物科学技术类专业创新教学体系，提出“理、工复合型”的教学模式，开设进展类课程和“研究型课程”，将重点实验室的自主科研成果引入教学课堂，推行实验课独立设课建设，改革实验教学内容和形式，依托重点实验室提高本科毕业论文水平。

Background: Xanthomonas campestris pathovar campestris (Xcc) is the causal agent of black rot disease of crucifers worldwide. The molecular genetic diversity and host specificity of Xcc are poorly understood. Results: We constructed a microarray based on the complete genome sequence of Xcc strain 8004 and investigated the genetic diversity and host specificity of Xcc by array-based comparative genome hybridization analyses of 18 virulent strains. The results demonstrate that a genetic core comprising 3,405 of the 4,186 coding sequences (CDSs) spotted on the array are conserved and a flexible gene pool with 730 CDSs is absent/highly divergent (AHD). The results also revealed that 258 of the 304 proved/presumed pathogenicity genes are conserved and 46 are AHD. The conserved pathogenicity genes include mainly the genes involved in type I, II and III secretion systems, the quorum sensing system, extracellular enzymes and polysaccharide production, as well as many other proved pathogenicity genes, while the AHD CDSs contain the genes encoding type IV secretion system (T4SS) and type III-effectors. A Xcc T4SS-deletion mutant displayed the same virulence as wild type. Furthermore, three avirulence genes (avrXccC, avrXccE1 and avrBs1) were identified. avrXccC and avrXccE1 conferred avirulence on the hosts mustard cultivar Guangtou and Chinese cabbage cultivar Zhongbai-83, respectively, and avrBs1 conferred hypersensitive response on the nonhost pepper ECW10R. Conclusion: About 80% of the Xcc CDSs, including 258 proved/presumed pathogenicity genes, is conserved in different strains. Xcc T4SS is not involved in pathogenicity. An efficient strategy to identify avr genes determining host specificity from the AHD genes was developed.

XopN was originally identified from Xanthomonas campestris pv. vesicatoria as an effector translocated into plant cells via the type III secretion system (T3SS), and is required for pathogenicity. We report here that the xopN homologue in the X. campestris pv. campestris genome, named xopXccN, also encodes a T3SS effector and is required for full virulence. We further demonstrate that expression of xopXccN is positively regulated by the key hrp (hypersensitive response and pathogenicity) regulators HrpG and HrpX.

The ColReColS two-component signal transduction system was originally characterized as a regulatory system involved in the capacity of root-colonizing biocontrol bacterium Pseudomonas fluorescens to colonize plant roots. There are three pairs of putative colRecolS twocomponent regulatory systems annotated in the phytopathogen Xanthomonas campestris pathovar campestris. Mutational studies revealed that one of them, named colRXC1049 and colSXC1050, is a global regulatory system involved in various cellular processes, including virulence, hypersensitive response and stress tolerance. Growth rate determination showed that, although the colRXC1049 and colSXC1050 mutants are not auxotrophic, colRXC1049 and colSXC1050 are required for the pathogen to proliferate well in standard media and host plants. Assays of bglucuronidase activities of plasmid-driven promoter-gusA reporters and/or semi-quantitative RT-PCR demonstrated that colRXC1049 and colSXC1050 positively regulate expression of hrpC and hrpE operons, and that expression of colRXC1049 and colSXC1050 is not controlled by key hrp regulators HrpG and HrpX.