MECHANISMS OF STABILIZATION OF B-HEMEPROTEINS

B-血红素蛋白的稳定机制

• 批准号: 6719095
• 负责人: JULIETTE T LECOMTE
• 金额: $ 21.68万
• 依托单位: PENNSYLVANIA STATE UNIVERSITY, THE
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-07-01 至 2007-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6719095
• 关键词: bacterial proteins; chemical models; chemical stability; cofactor; combinatorial chemistry; computer simulation; conformation; cytochrome b5 reductase; heme; hemoprotein; iron; molecular dynamics; molecular site; nuclear magnetic resonance spectroscopy; peptide chemical synthesis; protein binding; protein folding; protein structure function; proteomics; recombinant proteins; site directed mutagenesis; structural biology; thermodynamics

DESCRIPTION: The ability to design functional proteins for medical and other uses depends critically on understanding the relationship between amino acid sequence and physico-chemical properties. This proposal seeks to investigate the factors essential to the finely tuned capacity of b-hemoproteins to recognize and bind the heme group. The starting point is the apoprotein from cytochrome b5, a marginally stable globular protein able to bind the heme group reversibly and with high affinity. Heme binding induces structural changes, mostly in the alpha-helices of the binding site, and dynamic changes throughout the protein. The subprojects will combine molecular biology, optical spectroscopy, and multinuclear NMR spectroscopy to characterize these changes in wild-type apocytochrome b5 and variants. NMR relaxation and hydrogen exchange will be used to probe the motions of the empty binding site and the folded core. Thermodynamic parameters will be extracted from denaturation experiments and the affinity for the prosthetic group will be determined with a study of the kinetics of heme binding and release. Comparison with the holoprotein data will provide a map of the perturbations imposed by binding and a comprehensive energetic description to be exploited in heme-binding site design. To test the hypothesis that the heme binding loop of the cytochrome functions as an autonomous module, this loop will be inserted into a different protein (a small subunit with the topology of an SH3 domain). The properties of the constructs will be analyzed and compared to the original parent proteins. Alternative mechanisms for the efficient recognition and binding of the heme will be searched with the characterization of the heme-binding site of FixL, a rhizobial oxygen sensor protein. The information gathered on these artificial and natural proteins will help define the principles of construction of b hemoproteins suitable for the design of artificial heme-binders.

描述：能够设计用于医疗和其他功能的蛋白质

项目成果

Three-dimensional solution structure of PsaE from the cyanobacterium Synechococcus sp. strain PCC 7002, a photosystem I protein that shows structural homology with SH3 domains.

蓝藻聚球藻 PsaE 的三维溶液结构。

• DOI: 10.1021/bi00186a004
• 发表时间: 1994
• 期刊: Biochemistry
• 影响因子: 2.9
• 作者: Falzone,CJ;Kao,YH;Zhao,J;Bryant,DA;Lecomte,JT
• 通讯作者: Lecomte,JT

Similarities in structure between holocytochrome b5 and apocytochrome b5: NMR studies of the histidine residues.

全细胞色素 b5 和脱辅基细胞色素 b5 之间结构的相似性：组氨酸残基的 NMR 研究。

• DOI: 10.1021/bi00098a012
• 发表时间: 1991
• 期刊: Biochemistry
• 影响因子: 2.9
• 作者: Moore,CD;al-Misky,ON;Lecomte,JT
• 通讯作者: Lecomte,JT

A test of the relationship between sequence and structure in proteins: excision of the heme binding site in apocytochrome b5.

蛋白质序列和结构之间关系的测试：脱辅基细胞色素 b5 中血红素结合位点的切除。

• DOI: 10.1002/pro.5560070914
• 发表时间: 1998
• 期刊: Protein science : a publication of the Protein Society
• 作者: Constans,AJ;Mayer,MR;Sukits,SF;Lecomte,JT
• 通讯作者: Lecomte,JT

The solution structure of photosystem I accessory protein E from the cyanobacterium Nostoc sp. strain PCC 8009.

蓝藻发菜光系统 I 辅助蛋白 E 的溶液结构。

• DOI: 10.1021/bi9910373
• 发表时间: 1999
• 期刊: Biochemistry
• 影响因子: 2.9
• 作者: Mayer,KL;Shen,G;Bryant,DA;Lecomte,JT;Falzone,CJ
• 通讯作者: Falzone,CJ

Structural and thermodynamic encoding in the sequence of rat microsomal cytochrome b(5).

大鼠微粒体细胞色素 b(5) 序列的结构和热力学编码。

• DOI: 10.1002/bip.20892
• 发表时间: 2008
• 期刊: Biopolymers
• 影响因子: 2.9
• 作者: Lecomte,JulietteTJ;Mukhopadhyay,Kunal;Pond,MatthewP
• 通讯作者: Pond,MatthewP