权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

MD Study of Anthrax Edema Factor:Calmodulin Complexes

炭疽水肿因子：钙调蛋白复合物的MD研究

基本信息

批准号：
6595705
负责人：
Shuanghong Huo
金额：
$ 13.84万
依托单位：
CLARK UNIVERSITY (WORCESTER, MA)
依托单位国家：
美国
项目类别：
财政年份：
2003
资助国家：
美国
起止时间：
2003-05-01 至 2007-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6595705
关键词：
Bacillus anthracis active sites adenylate cyclase anthrax calmodulin computer simulation conformation exotoxins gene mutation molecular dynamics protein binding protein protein interaction protein structure function structural biology

项目摘要

DESCRIPTION (provided by applicant): The long-term goal of this project is to understand the precise conformational and dynamic requirements for both effective binding of calmodulin (CAM) to the anthrax edema factor (EF) and the generation of a fully functional adenylyl cyclase active site. A more detailed understanding of the structure and dynamics of the complex between the edema factor, calmodulin and substrate analogs should facilitate future efforts at designing structure-based drugs for the treatment of anthrax infections. This application proposes to investigate, using the molecular dynamics simulation (MD) approach, a large number of EF-CaM complexes containing single-site mutations in EF which are already known to affect either CaM binding or adenylyl cyclase catalytic activity. The specific aims of this proposal are to: 1) Characterize the conformational and dynamic consequences of EF mutations which give rise to known defects in CaM binding to EF. MD simulation input files for EF-CAM complexes containing EF mutations, at the EF:CaM interface, known to affect either CaM binding or CaM-induced adenylyl cyclase activity (L523A, K25A, Q526A, V529A and D647A), will be generated, and then subjected to MD simulations using Insight II software. The subsequent analysis will focus on conformational and dynamic differences in the MD trajectories between wild-type and EF variant complexes. MD results will be correlated with kinetic data on the ability of these EF variants to be activated by CaM, in order to determine the requirements for most effective binding of CaM to EF. 2) Characterize the conformational and dynamic consequences of EF mutations which adversely affect EF adenylyl cyclase activity. MD simulation input files for EF:CaM complexes containing EF mutations, at the EF adenylyl cydase active site, known to affect the CaM-induced adenylyl cyclase activity (K346R, K353R, K353A, H577N, H577D, N583A, N583Q, N583H, E588A, D50A and N639A) will be generated, and subsequently subjected to MD simulations. MD simulations will be performed, both in the absence and presence of bound substrate analog 3'-deoxy-ATP. Analysis of the resulting ME) trajectories will focus on the conformational and dynamic differences between the wild-type and EF variant complexes. All results will be correlated with available enzyme kinetic data on the ability of these EF variants to be activated by CaM, to determine the precise requirements for the development of a fully-functional EF adenylyl cyclase.

描述（由申请人提供）：本项目的长期目标是了解钙调蛋白（CAM）与炭疽水肿因子（EF）有效结合和产生全功能腺苷酸环化酶活性位点的精确构象和动态要求。对水肿因子、钙调素和底物类似物之间复合物的结构和动力学的更详细的了解，将有助于今后设计用于治疗炭疽感染的基于结构的药物。本申请提出了调查，使用分子动力学模拟（MD）的方法，大量的EF-CaM复合物含有单位点突变EF这是已知的影响钙调素结合或腺苷酸环化酶的催化活性。该提议的具体目的是：1）表征EF突变的构象和动态后果，其引起CaM与EF结合的已知缺陷。将生成EF：CaM界面处含有EF突变的EF-CAM复合物的MD模拟输入文件，已知该EF突变影响CaM结合或CaM诱导的腺苷酸环化酶活性（L523 A、K25 A、Q526 A、V529 A和D 647 A），然后使用Insight II软件进行MD模拟。随后的分析将集中在野生型和EF变体复合物之间的MD轨迹的构象和动力学差异。MD结果将与这些EF变体被CaM激活的能力的动力学数据相关，以确定CaM与EF最有效结合的要求。2)表征对EF腺苷酸环化酶活性产生不利影响的EF突变的构象和动态后果。将生成EF：CaM复合物的MD模拟输入文件，所述复合物在EF腺苷酸环化酶活性位点处含有已知影响CaM诱导的腺苷酸环化酶活性的EF突变（K346 R、K353 R、K353 A、H577 N、H577 D、N583 A、N583 Q、N583 H、E588 A、D50 A和N639 A），并随后进行MD模拟。将在不存在和存在结合底物类似物3 '-脱氧-ATP的情况下进行MD模拟。所得ME轨迹的分析将集中于野生型和EF变体复合物之间的构象和动力学差异。所有结果将与可用的酶动力学数据的能力，这些EF变体被激活的钙调素，以确定一个完全功能的EF腺苷酸环化酶的发展的精确要求。