Phylogenetic analysis and PCR-restriction fragment length polymophism identification of Salmonella based on grOEL gene sequence / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the value of grOEL gene sequence in phylogenetic analysis and typing of Salmonella.</p><p><b>METHODS</b>The grOEL gene was amplified by PCR, sequenced and analyzed using Bioedit and DNAstar software. The Salmonella strains were identified using PCR-restriction fragment length polymophism (PCR-RFLP).</p><p><b>RESULTS</b>The conservative and variable regions of grOEL gene of Salmonella serogroup were separately distributed and most of the small mutant regions distributed intermittently among the conservative regions. The phylogenetic tree of Salmonella based on the nucleotides differed from that generated based on the amino acid sequence. O8, O9 and O10 had the closest consanguinity, and 5 patterns were identified by PCR-RFLP.</p><p><b>CONCLUSION</b>The grOEL gene can be used as a genetic marker for phylogenetic analysis of Salmonella and also as a target sequence for Salmonella typing identification.</p>

Molecular subtyping of Staphylococcus aureus isolated from a severe food-poisoning / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the molecular types of Staphylococcus aureus isolated from a severe food-poisoning and to trace the possible strains.</p><p><b>METHODS</b>Real-time PCR was applied to detect nuc gene as a specific marker for S. aureus, mecA gene encoding methicillin resistance and 5 other genes encoding staphylococcal enterotoxins (sea, seb, see, sed, see). Isolates were also performed with 16S rRNA oligonucleotide sequence analyzing by DNAStar MegAlign 5.0 software and pulse-field gel electrophoresis (PFGE) by BioNumerics Version 4.0 software.</p><p><b>RESULTS</b>The nuc gene was detected from the 10 isolated strains, sea and seb genes were detected from 7 strains. There were 4 16 S rRNA types and 5 PFGE types found from all the strains.</p><p><b>CONCLUSIONS</b>Three relative S. aureus strains were involved in the severe food-poisoning at least. Molecular subtyping might give a molecular epidemiological evidence and support the source tracing of an outbreak.</p>