耐辐射菌的辐射抗性与其核内DNA结合蛋白相关性研究

Relateness of radioresistance and nuclear DNA-binding protein in deinococcus radiodurans.

本文采用地高辛 (DIG)标记染色体DNA作为探针 ,South -Western印迹法检测DNA结合蛋白 (DBP) ,对耐辐射菌D .radiodurans的DBP进行N -末端氨基酸序列分析。研究结果表明 :在野生型耐辐射菌中存有八种DBP的特征蛋白 (它们的分子量分别为 12 2 ,93 ,3 3 ,2 9,16,15 ,14和 12kDa) ;经氨基酸序列分析发现其中 93kDa和 3 3kDa可能为新的蛋白质 ;这两种新DBP的表达水平随培养基和培养时间的不同而异。提示耐辐射菌的DBP ,尤其是 93kDa和 3 3kDa的DBP与其辐射抗性可能有密切关系。

The exploration of the role of DNA-binding proteins(DBPs) from a radioresistant bacterium i.e. Deinococcus radiodurans(D.radiodurans).The DBPs from three wild type of D.radiodurans i.e.MR 1,KR 1 and Sark were determined by south-western bloting using the chromosomal DNA labeled with digoxin as a probe,and the N-terminal AA sequence of some DBPs was analysed.Results showed that there are 8 kinds of characterictic DBPs in the wild types of radioresistent bacterium whose molecular weights were 122,93,33,29,16,15,14and 12 kDa,among whom,the DBPs of 93 and 33kDa from wild type of KR 1 were found to be novel proteins by the AA Sequence analysis.The expression levels of the two DBPs change with different culture media at different culture time.It was suggested that the DBPs,especially the DBPs of 93 and 33 kDa,were closely related to the radioresistance of D.radiodurans.