Inhibition of DNA restrictive endonucleases by aqueous nanoparticle suspension of methanophosphonate fullerene derivatives and its mechanisms

• 来源期刊: 中国科学B辑（英文版）
• 年，卷（期）: 2009,（5）
• 页码范围: 626-631
• 页数: 6页
• 语种: 英文
• DOI: 10.1007/s11426-009-0030-2

摘要

Aqueous nanoparticle suspension of fullerene and its derivatives are currently attracting much atten-tion. To determine the effects of aqueous nanoparticle suspension of a mono-methanophosphonate fuIlerene and bis-methanophosphonate fuIlerene (denoted as n-MMPF and n-BMPF, respectively) on the activities of ONA restrictive endonucleases, plasmid pEGFP-N1 was cleaved at a single but differently restrictive site by EcoR I, BamH I, and isozymes Cfr9 I and Xma I, respectively. Both n-MMPF and n-BMPF inhibited the activity of EcoR I, while n-BMPF exhibited stronger inhibition than n-MMPF. Addi-tion of n-BMPF into reaction mixtures inhibited the activities of all the four enzymes, and IC50 values for EcoR I, BamH I, Cfr9 I and Xma I were 4.3, 30, 11.7 and 8.3 μmol/L, respectively. When EcoR I was completely inhibited by n-BMPF, addition of excess amounts of pEGFP-N1 could not produce the product linear plasmid; however, increase of EcoR I amounts antagonized EcoR I inhibition of n-BMPF. Two scavengers of reactive oxygen species (ROS), mannitol and sodium azide at the concentrations of 2-10 mmool/L, did not reverse inhibition of n-BMPF, implying that this inhibition probably is not corre-lated to ROS. These results suggested that aqueous nano-fullerenee might act as inhibitors of DNA restrictive endonucleases.