摘要
试验旨在筛选产淀粉酶的芽孢杆菌菌株,用于生产淀粉酶及作为饲料益生菌制剂。通过产淀粉酶培养基筛选具有产淀粉酶能力的芽孢杆菌,采用形态观察、生理生化测定及16S rRNA基因序列分析进行菌株鉴定;通过生长曲线、培养温度、pH值及NaCl耐受性测定,研究该菌株的生长特性;利用全基因组分析该菌株的遗传信息,挖掘并分析其产淀粉酶基因。结果表明,筛选获得产淀粉酶能力的菌株FJAT-16537,该菌株的淀粉酶、蛋白酶和纤维素酶活性分别为69.11、94.65和132.45 U/mL。经形态学、生理生化及16S rRNA鉴定,该菌株为蜡状芽孢杆菌(Bacillus cereus)。在20~50℃、pH值5.0~11.0及NaCl添加量为0~2.0%时,该菌株均能生长。菌株FJAT-16537的全基因组序列为5883215 bp,GC含量为35.38%。该菌株的基因组中共预测到8个与次级代谢产物合成相关的基因簇,筛查到11个与产淀粉酶相关的基因,4个与产蛋白酶相关的基因,7个与产纤维素酶相关的基因。研究表明,菌株FJAT-16537具有产淀粉酶、蛋白酶及纤维素酶等特性,其基因组中含有与之相关的酶基因,且该菌株中具有抑菌活性物质相关的基因簇。
The study aimed to screen amylase-producing Bacillus strains for the production of amylase and as feed probiotic preparations.Amylase-producing Bacillus strains were screened using amylase-producing medium,and the strains were identified through morphological observation,physiological and biochemical tests,and 16S rRNA gene sequence analysis.The growth characteristics of the strain were studied by measuring the growth curve,culture temperature,pH,and NaCl tolerance.The genetic information of the strain was analyzed using whole-genome sequencing to mine and analyze its amylase-producing genes.The results showed that strain FJAT-16537,which possesses amylaseproducing ability,was successfully screened.The amylase,protease,and cellulase activities of this strain were 69.11,94.65 and 132.45 U/mL,respectively.Morphological,physiological,biochemical,and 16S rRNA analyses identified the strain as Bacillus cereus.The strain exhibited good growth at temperatures ranging from 20 to 50℃,pH values from 5.0 to 11.0,and NaCl concentrations of 0 to 2.0%.The whole genome sequence of strain FJAT-16537 was 5883215 bp in length,with a GC content of 35.38%.The genome predicted eight gene clusters related to secondary metabolite synthesis,11 genes related to amylase production,four genes related to protease production,and seven genes related to cellulase production.The study demonstrates that strain FJAT-16537 possesses the ability to produce amylase,protease,and cellulase,and its genome contains related enzyme genes as well as gene clusters associated with antimicrobial activity.
作者
车建美
王阶平
郑雪芳
陈燕萍
陈冰星
刘波
CHE Jianmei;WANG Jieping;ZHENG Xuefang;CHEN Yanping;CHEN Bingxing;LIU Bo
出处
《饲料研究》
北大核心
2025年第6期94-101,共8页
Feed Research
基金
中央引导地方科技发展专项(项目编号:2022L3020)
农业高质量发展超越“5511”协同创新工程(项目编号:XTCXGC2021019)。
