Detection of intestinal microflora from mice affected by macrolide antibiotics

Macrolide antibiotics are widely used for treatment of community-acquired infectious diseases, but its side effects have not been thoroughly investigated, especially on the intestinal tract. Erythromycin, roxithromycin and azithromycin are macrolide antibiotics sharing similar chemical structure and their side effects on intestinal microflora of BALB/c mice were tested in this study. The bacterial composition of microflora was determined by 16S rRNA gene analysis conducted by polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE). The dominant bands were selected and sequenced to determine each individual bacteria. The total amount of 16S rRNA gene was reduced after macrolide antibiotics were administrated, and the specific pattern of bacterial composition was identified from each drug treatment. Bacteroides sp. and Clostridium butyricum str. were dominant intestinal organisms in all three drug-treated mice. This study reveals a significant change of bacterial composition of microflora on the tested mice for macrolide antibiotics.   Key words: Macrolide antibiotics, side effects, intestinal microflora, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE).