Eyederived Bacillus cereus genotype urrA and its relationship with disease condition and prognosis
1.Department of Laboratory Medicine, the Affiliated OphthalMetropia Hospital
of Wenzhou Medical College, Wenzhou 325027;
2.School of Laboratory Medicine, Wenzhou Medical College, Wenzhou 325027, China
Abstract：In order to establish a PCR assay for detecting Bacillus cereus from eyeorigin, and to understand the correlation among vrrA genotypes and disease severity and prognosis,the vrrA gene was selected as the target gene to design primers for establishing a PCR to detect Bacillus cereus. The PCR product was examined by agarose gel electronphoresis and analyzed by sequencing. Clustal software was applied for genotyping of the obtained vrrA gene sequences. Correlation among the infection of different vrrA genotypes and severity as well as prognosis of endophthalmitis were analyzed and compared. The established PCR could efficiently detect Bacillus cereus from eyeorigin with high sensitivity and specificity. The Bacillus cereus isolated from the specimens of endophthalmitis patients were classified as MT1, MT2 and MT3 vrrA genotypes. Among the five Bacillus cereus isolates, two were MT1 genotype, two were MT2 genotype and one was MT3 genotype. The endophthalmitis caused by infection of either MT1 or MT2 genotype of Bacillus cereus presented more seriously pathogenetic condition and unfavourable prognosis. On the contrast, the endophthalmitis caused by infection of MT3 genotype of Bacillus cereus presented more mildly pathogenetic condition and better prognosis. Our study shows the PCR using vrrA as the target gene could be used to rapidly detect Bacillus cereus from eyeorigin. There are diversities among the infection of different vrrA gene genotypes of Bacillus cereus and severity as well as prognosis of Bacillus cereus endophthalmitis.
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2011, Vol. 27 
