Efficient markerless gene deletions in Pseudomonas protegens Pf-5 using a upp-based counterselective system.

OBJECTIVES: Developing a counterselective system for efficient markerless gene deletions in biocontrol strain P. protegens Pf-5. RESULTS: We successfully implemented a markerless deletion of upp in Pf-5 to obtain the 5-FU resistant strain Pf5139. With this strain, we performed markerless gene deletions for each component of Gac/Rsm system and a 17 kb DNA fragment with the deletion ratio of 20 to 50%, and efficiently constructed a strain with triple deletions based on the suicide plasmid pJQ200UPP. In addition, there is no obvious connection between the deleted fragment length and the deletion ratio. CONCLUSION: The upp-based counterselective system in this study is efficient and valuable for markerless gene deletions in Pf-5, indicating that it has great potential in the study of gene function and in the application of genome reduction for Pseudomonas strains.

Association between INS-VNTR polymorphism and polycystic ovary syndrome in a Korean population.

Polycystic ovary syndrome (PCOS) is a common disorder in women of reproductive ages. But its etiology is not fully understood yet. Variability in the number of tandem repeats of the insulin gene (INS-VNTR) is known to associate with PCOS, and it is associated with an increased risk of diabetes mellitus and other cardiovascular diseases. The aim of our study was to analyze an association between the INS-VNTR polymorphism and PCOS in a Korean population. The -23/Hph I polymorphism was used as a surrogate marker for INS-VNTR polymorphism and a total of 218 PCOS patient and 141 control DNAs were analyzed by restriction fragment length polymorphism method. Statistical analysis of genotyping results were performed using HapAnalyzer. χ² test and logistic regression were used to analyze the association between two groups. A p value <0.05 was considered statistically significant. The frequencies of A/A and A/T genotypes indicated a similar change between PCOS patients and controls. In conclusion, there was no association between PCOS and INS-VNTR polymorphism (p = 0.0544, odds ratio = 1.69). Our present data demonstrate that INS-VNTR polymorphism is not related with PCOS in Korean women. Thus, it is suggested that INS-VNTR polymorphism is not a key factor in the etiology and the pathogenesis of PCOS in a Korean population.