Cephalopod Hemocyanins: Structure and Function

头足类血蓝蛋白：结构和功能

• 批准号: 9805570
• 负责人: Karen Miller
• 金额: $ 33万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9805570&HistoricalAwards=false
• 关键词: Cephalopod; Hemocyanins; Structure; Function

The study focuses on the structure and physiological function of hemocyanins, which are oxygen-carrying proteins found in the blood of some invertebrates. The amino acid sequence, and part of the 3-dimensional structure of one of these giant molecules (that from Octopus) has recently been determined by the investigator and her collaborators. The new work proposed will first examine the structure of a part of the gene for the Octopus hemocyanin, and then attempt to develop a system to express a portion of this gene in bacteria or other cells. This should ultimately allow directed mutation, to analyze the effects of particular amino acids on the oxygen binding function. The protein also contains attached carbohydrate groups; the composition and structure of representative ones will be determined, and their possible roles in determining protein structure and/or function examined. Finally, the program will focus on how portions of these giant molecules communicate with one another to regulate the cooperative binding of oxygen on many sites. This phenomenon of allosteric regulation is common to many other important proteins, and is still not completely understood.Hemocyanins are oxygen transport proteins found exclusively in molluscs and arthropods. The octopus hemocyanins are truly enormous molecules, with molecular weights in the millions. As a result of recent breakthroughs in structure and sequence analysis of these molecules, the investigators are poised to interpret the evolution and function of hemocyanin at a level of sophistication never before possible.

这项研究的重点是血蓝蛋白的结构和生理功能，血蓝蛋白是在一些无脊椎动物的血液中发现的携氧蛋白质。研究人员和她的合作者最近确定了其中一个巨大分子(章鱼分子)的氨基酸序列和部分三维结构。拟议中的新工作将首先检查章鱼血蓝蛋白基因的一部分结构，然后尝试开发一种系统，在细菌或其他细胞中表达该基因的一部分。这最终应该允许定向突变，以分析特定氨基酸对氧结合功能的影响。蛋白质还含有附着的碳水化合物基团；将确定具有代表性的碳水化合物的组成和结构，并研究它们在确定蛋白质结构和/或功能方面的可能作用。最后，该计划将专注于这些巨型分子的部分如何相互通信，以调节氧在多个位置上的协同结合。这种变构调节的现象在许多其他重要的蛋白质中都很常见，目前还不完全了解。血蓝蛋白是一种氧气运输蛋白，仅存在于软体动物和节肢动物中。章鱼血蓝蛋白是真正的巨大分子，分子量以数百万计。由于最近在这些分子的结构和序列分析方面取得了突破，研究人员准备以前所未有的复杂程度来解释血蓝蛋白的进化和功能。