Phospholipase C from Pseudomonas aeruginosa and Bacillus cereus:characterization of catalytic activi

来源 :Asian Pacific Journal of Tropical Medicine | 被引量 : 0次 | 上传用户:tlling06990702
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Objective:To study characteristics of phospholipases C(PLCs),their importance for producing microorganisms us well us the potential of their use for industrial purposes.Methods:PLC from Bacillus cereus(B.cereus) D101 was selected as an example of Gram-positive PLCs and PLC from Pseudomanas aeruginosa(P.aeruginosa) D183 of Gram-negative ones.Enzymes were partially purified by ammonium sulfate precipitation followed by membrane dialysis.Partially purified preparations were used to study effect of different factors on activities as well as in substrate specificity tests which were conducted using a turbidimetric assay method.Results:Maximum activity was at pH 7 and 8 and 40 ℃ for P.aeruginosa PLC,and pH 8-10 and 37 ℃ for B.cereus PLC.Both PLCs were inhibited by Pi at 5 mM or higher,whereas,PLC from B.cereus only was inhibited by EDTA.Activity of P.aeruginosa PLC was not affected by removing Zn~(2+) ions from reaction mixture or their replacement with Ca~(2+),Ba~(2+),Mg~(2+) or Mn~(2+)ions.Vis-a-vis,activity of B.cereus PLC was found to be metal ion dependent PLCs from both isolates were relatively thermostable and showed maximum affinity toward phosphatidylcholine.Sphingomyelin and phosphatidylethanolamine were not good substrates and phosphatidylinositol,phosphatidylserine,phosphatidylglycerol and cardiolipin could be considered nonsubstrates.Conclusions:Human body physiological conditions could favor activity of P.aeruginosa and B.cereus PLCs.These enzymes may participate in phosphate scavenging and virulence of producing isolates but not in autolysis.PLCs from both isolates are potential candidates for industrial use. Objective: To study characteristics of phospholipases C (PLCs), their importance for producing microorganisms us well us the potential of their use for industrial purposes. Methods: PLC from Bacillus cereus (B. cereus) D101 was selected as an example of Gram-positive PLCs and PLC from Pseudomanas aeruginosa (P. aeruginosa) D183 of Gram-negative ones. Enzymes were partially purified by ammonium sulfate precipitation followed by membrane dialysis. Partially purified preparations were used to study effect of different factors on activities as well as in substrate specificity tests which were conducted using a turbidimetric assay method. Results: Maximum activity was at pH 7 and 8 at 40 ° C. for P. aeruginosa PLC, and pH 8-10 and 37 ° C. for B. cereus PLC. 5 mM or higher, while, PLC from B. cereus only was inhibited by EDTA. Activity of P. aeruginosa PLC was not affected by removing Zn ~ (2+) ions from reaction mixture or their replacement with Ca ~ (2+), Ba ~ (2 +), Mg ~ (2+) or Mn ~ (2+) ions.Vis-a-vis, activity of B.cereus PLC was found to be metal ion dependent PLCs from both isolates were relatively thermostable and showed maximum affinity toward phosphatidylcholine.Sphingomyelin and phosphatidylethanolamine were not good substrates and phosphatidylinositol, phosphatidylserine, phosphatidylglycerol and cardiolipin could be considered nonsubstrates.Conclusions: Human body physiological conditions could favor activity of P. aeruginosa and B. cereus PLCs. These enzymes may participate in phosphate scavenging and virulence of producing isolates but not in autolysis. PLCs from both isolates are potential candidates for industrial use.
其他文献
音乐教育是高校教育不可或缺的关键性组成要素,也是文化建设的核心内容,有利于促进大学生身心发展。在素质教育背景下,如何让大学生健康成长已成为新时期音乐教育发展中值得
游戏是人类发展中不断创新的活动,而且人类在游戏中也能取得收获,对人的个性发展有着重要的作用.游戏作为幼儿非常喜欢的活动,在游戏中培养幼儿个性发展是非常重要的.因此,教
目前许多城市早已大力推广和实施公共自行车系统,但是占地面积较大的驻车站点只能停放寥寥十几辆自行车成了一大难题,使得市民不仅借车难,停车也难。根据绿色节能环保、提高
如今,随着微信的普及,微信公众号已成为每家企业的重要宣传平台。作为公司市场部的一员,我负责每期的微信制作与后台运营,于是每年的微信认证任务自然也落在了我身上。微信认
民族民间舞蹈是学校开展艺术教育的重要内容,教学过程中教师要不断的培养学生的审美品位,并给学生打下坚实的文化基础。民族民间舞蹈教学中不断的渗入中国民族的传统文化,并
介绍了减少边远井场电力费用的方法 ,即安装网络基间抽控制器 ,较高液面时启动抽油泵抽油 ,较低液面时停抽 ,减少抽汲运行时间 ,从而达到减少实际耗电量的目的。经在Lander油
请下载后查看,本文暂不支持在线获取查看简介。 Please download to view, this article does not support online access to view profile.
在水库现场试验了RIS K2型探地雷达探测水库冰厚度的能力,试验时所用天线频率为600MHz;同步钻孔测量雷达探测处的冰厚度;以及在一个点上取样测试分析冰晶体、冰内气泡和冰密
介绍采用数据库技术编程用中规模集成电路实现组合逻辑函数的软件设计.软件完成集成数据选择器或译码器下,输入变量表达式,组合逻辑函数的真值表和用户操作界面的设计.
[目的]测定增效吡虫啉对豆蚜的毒力。[方法]采用浸渍法测定了2种增效吡虫啉对豆蚜的24 h致死作用,同时以市售的35%吡虫啉悬浮剂为对照。[结果]31%增效吡虫啉悬浮剂SE-6-4防治