灰色链霉菌RX-17溶菌酶R1的纯化及性质研究  

Purification and Some Properties of Bacteriolytic Enzyme R1 from Streptomyces griseus RX-17

作　　者：赵昕[1] 任光文[1] 屠晓平[1] 张玉臻[1] 

机构地区：[1]山东大学微生物技术国家重点实验室,济南250100

出　　处：《微生物学报》2003年第6期758-763,共6页Acta Microbiologica Sinica

摘　　要：通过硫酸铵分级沉淀 ,CM SephadexC 5 0、CM SepharoseFastFlow离子交换层析及Seph adexG 75凝胶过滤层析 ,从灰色链霉菌 (Streptomycesgriseus)RX 1 7的发酵上清液中得到了电泳纯的溶菌酶R1 ,回收率 6 89%。测得该酶分子量和等电点分别为 1 6 8kD和 9 1 0 ,作用于变链球菌 (Streptococcusmutans)Ingbritt的最适温度和pH分别为 70℃和 6 6。R1酶在 5 0℃以下及pH6～ 9的范围内保持稳定 ,60℃保温 1h ,残存酶活 2 0 3%。Mg2 +对酶有激活作用 ,而Zn2 +、Cu2 +、Fe2 +、Cd2 +、Pb2 +则使酶完全丧失活性 ,螯合剂、盐酸羟胺、碘乙酸抑制酶活 ,β 巯基乙醇及表面活性剂则对溶菌有部分促进作用。R1酶溶菌谱广泛 ,对多种卵清溶菌酶不能作用的G+、G 细菌均有溶解能力 ,对变链球菌、金黄色葡萄球菌 (Staphylococcusaureus)、乳杆菌(Lactobacillus)等则呈现高活性。Bacteriolytic enzyme R1 was purified to electrophoretic homogeneity with the recovery of 6.89% activity by ammonium sulfate precipitation, CM-Sephadex C-50, CM-Sepharose Fast Flow and Sephadex G-75 chromatography from the culture supernatant of Streptomyces griseus RX-17. The molecular weight and PI of R1 were 16.8kD and 9.10. The optimal temperature and pH for R1 against Streptococcus mutans Ingbritt were 70℃ and 6.6, respectively. Below 50℃ and at range pH 6～10, R1 was stable. While treated at 60℃ for 1 hour, the residual activity was only about 20.3%. Zn 2+ ,Cu 2+ ,Fe 2+ ,Cd 2+ and Pb 2+ could completely inactivate the enzyme. Chelating agents、hydroxylamine hydrochloriae、 Monoiodoacetic acid inhibited the lytic activity against Streptococcus mutans Ingbritt, whereas Mg 2+ 、2-Mercaptoethanol and some surfactants could stimulate the activity. The enzyme had a broad bacteriolytic spectrum against many G +、G - bacteria which were resistant to egg-white lysozyme. Especially high activity was shown on Streptococcus mutans, Staphylococcus aureus and Lactobaillus .

关 键 词：灰色链霉菌 溶菌酶 纯化 性质 变链球菌 

分 类 号：Q936[生物学—微生物学] Q949.32