Fe_4S_4簇合物中μ_3－S的酸不稳定性研究  

The Study on Acid Lability of μ_3-S Of Fe_4S_4 Cluster

作　　者：黄静伟 张鸿图 周明玉 杨如 万惠霖 蔡启瑞 

出　　处：《厦门大学学报（自然科学版）》1995年第5期737-740,共4页Journal of Xiamen University：Natural Science

基　　金：国家基础性研究重大关键项目

摘　　要：在室温下，用ＵＶ－２１００型紫外可见分光光度计考察各种ｐＨ值的缓冲液对Ｆｅ＿４Ｓ＿４簇合物中μ＿３－Ｓ的破坏程度，藉此考察ＦｅＭｏ－ｃｏ中μ＿３－Ｓ的酸不稳定性．结果表明Ｆｅ＿４Ｓ＿４簇合物中的μ＿３－Ｓ在ｐＨ２～３时最不稳定，极易受酸破坏；ｐＨ３～４时，Ｆｅ＿４Ｓ＿４簇中的μ＿３－Ｓ受酸影响较ｐＨ２～３时小；ｐＨ４～５时，Ｆｅ＿４Ｓ＿４簇基本稳定，其中的μ＿３－Ｓ基本不受破坏．结合蛋白环境对金属中心有巨大保护作用，在生物提取ＦｅＭｏ－ｃｏ的过程中酸解对蛋白键合的ＦｅＭｏ－ｃｏ骨架μ＿３－Ｓ的破坏是很微弱的，但对裸露的或外围蛋白受到破坏的ＦｅＭｏ－ｃｏ骨架μ＿３－Ｓ的破坏却是相当大的．The acid lability of μ_3-S of Fe_4S_4 cluster was observed by Shimadzu UV-2100type spectrophotometer,when the buffers with different pH were added into Fe_4S_4-DMF solutionat room temperature. The experiments suggested that μ_3-S of Fe_4S_4 cluster was the most unstableand easy to be destroyed at pH 2～3; at pH 3～4, the acid lability of μ_3-S is lower than the for-mer′s;at pH 4～5,the Fe_4S_4 cluster is almost stable and its μ_3-S is almost not to be destroyed.Related to the large protection protein, it is evident that μ_3-S of the protein-bonded FeMo-co isslightly destroyed during the isolation of FeMo-co from MoFe-protein; but when FeMo-co is ex-posed or its protein has been destroyed, the decomposition of μ_3-S of FeMo-co is very large.

关 键 词：Fe4S4 酸不稳定性 簇状化合物 

分 类 号：O614.811[理学—无机化学]