热稳定性
极端微生物
蛋白质进化
化学
天体生物学
计算生物学
生物
嗜热菌
生物化学
酶
基因
作者
R Scandurra,Valerio Consalvi,Roberta Chiaraluce,Laura Politi,Paul C. Engel
出处
期刊:Biochimie
[Elsevier]
日期:1998-11-01
卷期号:80 (11): 933-941
被引量:134
标识
DOI:10.1016/s0300-9084(00)88890-2
摘要
Thermostability of a protein is a property which cannot be attributed to the presence of a particular amino acid or to a post synthetic modification. Thermostability seems to be a property acquired by a protein through many small structural modifications obtained with the exchange of some amino acids and the modulation of the canonical forces found in all proteins such as electrostatic (hydrogen bonds and ion-pairs) and hydrophobic interactions. Proteins produced by thermo and hyperthermophilic microorganisms, growing between 45 and 110 degrees C are in general more resistant to thermal and chemical denaturation than their mesophilic counterparts. The observed structural resistance may reflect a restriction on the flexibility of these proteins, which, while allowing them to be functionally competent at elevated temperatures, renders them unusually rigid at mesophilic temperatures (10-45 degrees C). The increased rigidity at mesophilic temperatures may find a structural determinant in increased compactness. In thermophilic proteins a number of amino acids are often exchanged. These exchanges with some strategic placement of proline in beta-turns give rise to a stabilization of the protein. Mutagenesis experiments have confirmed this statement. From the comparative analysis of the X-ray structures available for several families of proteins, including at least one thermophilic structure in each case, it appears that thermal stabilization is accompanied by an increase in hydrogen bonds and salt bridges. Thermostability appears also related to a better packing within buried regions. Despite these generalisations, no universal rules can be found in these proteins to achieve thermostability.
科研通智能强力驱动
Strongly Powered by AbleSci AI