Establishment of a novel identification system for Enterotoxigenic Bacteroides fragilis using CRISPR-Cas13 and bacteriophage technology

产肠毒素脆弱类杆菌(ETBF)是引起结肠癌炎症性腹泻的病原菌。世界上5%-20%的人口无症状地携带这种病毒。因此，需要快速、简便的检测方法来妥善预防和治疗该病。我们实验室利用CRISPR-Cas13a系统自主研发了一种抗菌衣壳。本应用旨在利用脆弱类杆菌的bft基因建立一种简单的鉴定体系。在第一年，我取得了一些成果：我收集了215株脆弱类杆菌(BF)菌株，其中12株BFT-1阳性，8株BFT-2阳性，1株BFT-3阳性。我对50个菌株进行了全基因组测序，完成了对它们基因组的全面调查，发现11个菌株在它们的基因组中显示了前噬菌体序列。根据MIC结果，6株对抗生素敏感且基因组中不携带噬菌体的菌株适合携带衣壳。

Enterotoxigenic Bacteroides fragilis (ETBF) is the cause of inflammatory diarrhea of the colon and intestinal cancer. 5-20% of the world's population carries this strain asymptomatically. Therefore, rapid and easy detection methods are needed to properly prevent and treat the disease. Our laboratory has independently developed an antibacterial capsid using the CRISPR-Cas13a system. This application aims to establish a simple identification system using the bft gene of Bacteroides fragilis. This study culminates in the development of new therapeutic strategies for controlling gut microbiota in the gut microbiota community.In the first year, I have achieved some results: I collected 215 Bacteroides fragilis (BF) strains, including 12 bft1-positive, 8 bft-2-positive, and 1 bft-3-positive strain. I performed whole-genome sequencing on 50 strains, completing a comprehensive survey of their genomes and found out 11 strains revealed prophage sequences in their genome. Based on the results of MIC, six strains that susceptible to antibiotics and not carry prophage in their genome, were suitable to carry Capsid.