• Sonuç bulunamadı

血紅蛋白結構變動與

N/A
N/A
Protected

Academic year: 2021

Share "血紅蛋白結構變動與"

Copied!
2
0
0

Yükleniyor.... (view fulltext now)

Tam metin

(1)

血紅蛋白結構變動與

溫度效應之關係 b2His 與 b6Glu 部位結構之

重要性

The Structure Basis of Temperature Effect on Hemoglobin: The

Involvement of β2 His and β6 Glu

中文摘要 血紅蛋白是生物體內賴以維生的分子。過去的研究指出,其攜氧能力受到許多調 節因子調控而有所不同,溫度即為一重要因子。但對於溫度調控攜氧機能與血紅 蛋白構造在分子層面上之關係則尚未被解明,本研究擬以基因蛋白工程之方法來 探討。 本篇論文主要是求了解血紅蛋白中央空腔的 β2His 與 β6Glu 等位置構造對 血紅蛋白攜氧與溫度效應之關係而進行研究。先利用電腦完成血紅蛋白胺基酸序 列之比對與重組分子結構的模擬後,將中央空腔內上述之位置進行改變以引發分 子結構上的變動,作為實驗設計之分析確認。在實驗上利用 PCR mutagenesis 得 到其蛋白基因之變異株後,再轉殖進入特定蛋白表達系之大腸桿菌中大量製造出 重組血紅蛋白,並以一系列之管柱層析法純化並輔以可見光譜及電泳分析鑑定後 得到純度較高的重組血紅蛋白而進行功能及性能之測試。結果與先前所發現之天 然突變血紅蛋白相符合且重組血紅蛋白與人類血紅蛋白對於溫度的敏感性有差 異。r Hb (βH2E)與 r Hb (βH2E, E6K)之焓(DH)於酸鹼度 pH7.4 下,變化分別為 -5.39 及-2.47,即對於溫度的敏感度較人類血紅蛋白及重組野生株為低。肯定位 於血紅蛋白中央空腔之 β2 與 β6 位置對於溫度效應調控血紅蛋白之功能有 所關聯。

英文摘要

Hemoglobin (Hb) is a vital oxygen-transporting molecule in the aerobic organism. Previous studies have shown that oxygen carrying function of Hb is regulated by various allosteric coffectors where temperature is an important one. However to date, the structure basis of enthalpy change in oxygen binding properties of Hb has not been elucidated. To investigate the positions in Hb that involved in the temperature effect, we have produced three site-directed mutant recombinant hemoglobins (rHbs): r Hb (βH2E), r Hb (βH2E, E6K) and r Hb (βH2E, K82N, N108D) in this study. Through a series of purification by chromatography, the obtained pure r Hbs have been subjected to oxygen binding function and stability analyses.

Results obtained from this study suggest that these residues: His β2 and Glu β6 in b globin indeed contribute to in the temperature effect of human adult hemoglobin (HbA) and consist with previous report by M. F. Perutz et al. that the electrostatic

(2)

Referanslar

Benzer Belgeler

[2] In our case, we performed coronary CT in which we detected the abnormal origin of the LCA from the pulmonary artery and visualized the course of the LCA with

Phillip PHIRI: AN EXPERIMENTAL STUDY OF THE EFFECT OF TEMPERATURE, PRESSURE AND FLOW RATE ON MODIFIED ZADRA GOLD ELUTION PROCESS... I hereby declare that, all the information

I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work.. Name, Last name :

It is stated on the Website of the official state and planning organisation that: “Banks are free to keep foreign currency, import and export transaction, accept foreign

Thermocouples are a widely used type of temperature sensor for measurement and control and can also be used to convert a temperature gradient into electricity.. Commercial

Snakehead fish (Channa maculata) is a bimodal breathing fish, able to acquire oxygen from water as well from air directly.. Hemoglobin of this fish may therefore be an excellent

 Previous studies by others and this laboratory on the allosteric effect of hem oglobins have suggested that the electrostatic replusive cavity at the center of tetrameric moiety

Results obtained from this study suggest that these residues: His β2 and Gl u β6 in b globin indeed contribute to in the temperature effect of human ad ult hemoglobin (HbA) and