产几丁质酶的无色杆菌ZWW8的发酵产酶及酶学性质研究  

Study on Enzyme Production of a Chitinase-producing Strain Achromobacter sp.ZWW8 by Fermentation and Its Enzymatic Characterization

作　　者：张瑶心 王亮节 郑文 徐汉琴 郑恋 钟静 ZHANG Yao-xin;WANG Liang-jie;ZHENG Wen;XU Han-qin;ZHENG Lian;ZHONG Jing(School of Chemistry and Life Science,Hubei University of Education,Hubei Key Laboratory of Purification and Application of Plant Anticancer Active Ingredients,Wuhan 430205)

机构地区：[1]湖北第二师范学院化学与生命科学学院植物抗癌活性物质提纯与应用湖北省重点实验室,武汉430205

出　　处：《生物技术通报》2021年第4期96-106,共11页Biotechnology Bulletin

基　　金：湖北省教育厅科研计划项目中青年人才项目(Q20173008)。

摘　　要：从湖北武汉地区虾壳堆积土壤中筛选得到一株分泌胞外几丁质酶菌株ZWW8,通过16S rDNA序列比对发现其属于无色杆菌属;通过碳源、氮源、温度、培养基pH、培养时间的单因素优化实验获得ZWW8菌株的最优发酵条件,该菌株在添加0.5%几丁质胶体,0.5% NH_4Cl,初始pH 7.0的培养基中,于37℃培养2 d后胞外上清酶活力可达到33.9 U/L,是优化前酶活力的8倍;通过检测ZWW8菌株分泌胞外几丁质酶的酶学性质发现,其最适反应pH为5,最适反应温度为50℃。Ni~(2+)和Ca~(2+)能提高几丁质酶活性,而Hg~(2+)、Cu~(2+)和Zn~(2+)能明显抑制酶活。此外,几丁质酶还能在高盐条件维持活性和稳定性,并特异性结合几丁质。通过几丁质亲和层析纯化的胞外几丁质酶,在透析除去尿素后仍然具有活性。ZWW8菌株的几丁质酶具有独特的酶学特性,使其能作为高效稳定的生物催化剂,为实现在工业、农业和医学方面的应用潜能,以及几丁质资源的开发和利用奠定基础。A extracellular chitinase-secreting bacterium ZWW8 was isolated from shrimp shell-accumulated soil in Hubei and identified as Achromobacter spp.via 16S rDNA sequence analysis.The fermentation conditions for chitinase production by the strain ZWW8 were optimized using the single-factor experiment,and the optimal fermentation conditions were as follows:0.5%colloidal chitin,0.5%ammonium chloride,initial medium pH 7.0,and 37℃for 2 d.Under the optimized fermentation conditions,the highest chitinase activity in the supernatant reached 33.9 U/mL,which was 8 times of the activity before optimization.By detecting the enzymatic properties of extracellular chitinase secreted by ZWW8 strain,it was revealed that the optimal temperature of chitinase produced by Achromobacter sp.ZWW8 was 50℃and the optimal pH was 5.Ni2+and Ca2+increased chitinase activity,but Hg2+,Cu2+and Zn2+significantly inhibited the enzymatic activity.Meanwhile,the chitinase not only exhibited activity and stability at high salt concentrations,but also showed chitin binding capacity.The extracellular chitinase from the fermented broth purified by chitin resin column demonstrated high activity after urea removed by dialysis.The chitinase by Achromobacter sp.ZWW8 possesses excellent enzymatic properties,making it a highly efficient and stable biocatalyst,which lays a foundation for exploring its application potential in industry,agriculture and medicine,as well as the development and utilization of chitin resources.

关 键 词：无色杆菌 几丁质酶 发酵优化 酶学性质 耐盐 

分 类 号：TQ925[轻工技术与工程—发酵工程]