肠癌患者肠道菌群中大肠埃希菌携带β-葡萄糖醛酸酶基因的鉴定与特征

Identification and Characterization of E. coli Carrying β-Glucuronidase Gene in the Patients with Colorectal Cancer

目的探讨肠癌患者肠道菌群中大肠埃希菌携带β-葡萄糖醛酸酶(β-Glucuronidase,GUS)基因序列变化特征,为肠癌的防治与诊断提供新的思路.方法采集肠癌患者晨起粪便,常规方法分离大肠埃希菌,提取细菌基因组DNA,设计GUS基因特异性引物,进行PCR扩增及测序分析.结果 10例肠癌患者肠道菌群中大肠埃希菌均携带GUS基因,与Gen Bank(Acession No.S69414.1)uid A基因序列同源性为99%,分别在第1141和1148位A缺失,第1149位A突变成T,第1158位A突变成G.结论肠癌患者大肠埃希菌GUS基因同时出现基因突变和缺失,可成为肠癌诊断的新标记物.

Objective To explore the variation characteristics of gene sequences in β-glucuronidase （ E. coli in the patients with colon cancer, and to provide new ideas for the prevention and diagnosis of GUS） by colorectal cancer. Method Early morning stool of the patients were collected. E. coli was seperated, and genomic DNA was extracted from it. Specific primers for GUS gene were designed and amplified by PCR technique. Then, the PCR product underwent sequencing analysis. Results The GUS gene was detected in 10 cases of colorectal cancers, and was 99% homologious with uidA gene sequences in GenBank （Acession No. S69414. 1 ）. However, the deletion of base A occurred at the 1141th and 1148th position, and the base A changed into T at the 1149th and changed into G at the 1158th simultaneously. Conclusion The situation of deletion and mutation of uidA gene in GUS carried by E. coli from the patients might become a new marker in the diagnosis of colorectal cancer.