小龙虾肠道细菌群落多样性及产蛋白酶细菌的筛选

【背景】养殖动物对饲料的消化利用往往与肠道菌群密切相关。【目的】揭示小龙虾肠道细菌群落组成,并从小龙虾肠道筛选产蛋白酶细菌。【方法】在Illumina MiSeq PE300平台对细菌16S rRNA基因V3-V4区进行高通量测序,分析小龙虾肠道细菌群落多样性;通过酪蛋白平板法筛选产蛋白酶细菌并进行分子生物学鉴定。【结果】小龙虾肠道细菌优势门包括变形菌门、软壁菌门、厚壁菌门、拟杆菌门等4个门,累计占比为98.53%;优势属包括柠檬酸杆菌属、支原体科Candidatus_Bacilloplasma暂定属、哈夫尼菌属、肠球菌属、拟杆菌属、梭菌科未分类属、希瓦氏菌属等7个属,累计占比为91.67%。通过酪蛋白平板法筛选的产蛋白酶细菌来自哈夫尼菌属、柠檬酸杆菌属、克雷伯氏菌属和芽孢杆菌属。【结论】小龙虾肠道细菌核心类群在蛋白质消化利用中发挥了重要作用。

Diversity of bacterial community and screening of protease producing bacteria in red swamp crayfish (Procambarus clarkii) intestine

Background] The digestion and utilization of feed by cultured animals are often closely related to intestinal microbiota. Objective] The composition of intestinal bacterial community of red swamp crayfish (Procambarus clarkii) was studied, and protease producing bacteria was screened from the intestinal tract of red swamp crayfish. Methods] The bacterial community diversity in crayfish intestinal tract was analyzed by sequencing the bacterial 16S rRNA gene V3?V4 region on Illumina MiSeq PE300 platform, and the protease producing bacteria were screened by casein plate method and identified by molecular biology methods. Results] The most prevalent bacterial phyla were Proteobacteria, Tenericutes, Firmicutes and Bacteroidetes in crayfish intestinal tract, accounting for 98.53% in total. There were 7 prevalent genera of Citrobacter, Candidatus_ Bacilloplasma, Hafnia, Enterococcus, Bacteroides, unclassified_f_Clostridiaceae and Shewanella, accounting for 91.67% in total. The protease producing bacteria screened by casein plate method belonged to Hafnia, Citrobacter, Klebsiella and Bacillus. Conclusion] The core groups of bacteria in red swamp crayfish intestinal tract played an important role in protein digestion and utilization.