ABSTRACT
<p><b>OBJECTIVE</b>To investigate the structural changes inintestinal flora and metabolic changes in type 2 diabetic patients with obesity(BMI≥40 kg/m)by sequencing the 16S rRNA genes.</p><p><b>METHODS</b>Stool samples were collected from 4 diabetic patients before and after gastric bypass surgery for extraction of the total DNA. The diversity of the intestinal flora in the samples was investigated by 16S rRNA sequencing. After surgery, the changes in glucose and lipid metabolism were evaluated in the patients, and the changesin body mass index (BMI) and waist to hip ratio were assessed at 3 month intervals.</p><p><b>RESULTS</b>After gastric bypass, the patient's BMI, waist to hip ratio, glucose metabolism and lipid metabolism gradually recovered the normal levels. The proportion of Bacteroidetesis increased and the proportions of Firmicutes and Proteobacteria decreased in the intestinal bacteria after the surgery.</p><p><b>CONCLUSION</b>Gastric bypass surgery can effectively alleviate the condition of obese patients with type 2 diabetes and improve the composition of the intestinal flora.</p>