Kénani A, Bailly C, Helbecque N, Catteau J P, Houssin R, Bernier J L, Hénichart J P
Unité INSERM N. 16, Lille, France.
Biochem J. 1988 Jul 15;253(2):497-504. doi: 10.1042/bj2530497.
A comparison of the complexing properties of metal ions and O2 activation by bleomycin-A2 (BLM-A2) and deglyco-BLM-A2 is presented. Deglyco-BLM-A2 is obtained from the parent derivative by HF cleavage of the sugar moiety followed by h.p.l.c. purification. Complexing of Cu(II) and Fe(III) is studied by using c.d. and e.s.r. spectroscopy. Spin-trapping experiments in the presence of phenyl N-t-butylnitrone indicated lower production of free radicals by deglyco-BLM-A2. Finally, a proposal is made to explain this discrepancy, focusing on the probable role of the gulose-mannose moiety acting as a protecting pocket, comparable with the pocket and picket-fence porphyrins described for haemoproteins.
本文介绍了博来霉素A2（BLM-A2）和去糖基博来霉素A2的金属离子络合特性及O2活化的比较。去糖基博来霉素A2是通过对母体衍生物的糖部分进行HF裂解，然后进行高效液相色谱纯化而得到的。通过圆二色光谱（c.d.）和电子自旋共振光谱（e.s.r.）研究了Cu（II）和Fe（III）的络合情况。在苯基N-叔丁基硝酮存在下的自旋捕获实验表明，去糖基博来霉素A2产生的自由基较少。最后，提出了一个解释这种差异的建议，重点关注古洛糖-甘露糖部分可能作为保护口袋的作用，这与血红蛋白中描述的口袋和栅栏卟啉类似。
