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1.
应用可见吸收光谱首次研究了铜锌超氧歧化酶(Cu2Zn2SOD)活性中心金属离子在一定缓冲溶液中与无机氯化钴的直接相互作用。讨论了加入不同比例量的氯化钴、不同的pH值、不同酸盐及作用的平衡时间对这种相互作用的影响。结果发现,CoCl2中的Co(Ⅱ)与Cu2Zn2SOD中的Zn(Ⅱ)有交换作用,形成部分的Cu2中的Co2SOD,且上述四种因素对此均有不同程度的影响。本研究开创了金属酶活性中心金属离子与外加无机金属化合物的直接相互作用的研究。  相似文献   

2.
我们首次发现的铜锌超氧歧化酶(Cu2Zn2SOD)与氨基酸等发生直接相互作用的现象,是一种前人未研究过的重要的生化新现象[1]。在此新发现的基础上,本文用ICP,VIS,NMR和酶活性测定等方法,又从不同角度拓展研究了Cu2Zn2SOD酶与两类不同化合物,即无机氯化钴(CoCl2)、有机组氨酸钴(Co(Ⅱ)(His)n)的直接相互作用,发现酶活性中心金属离子同样与外加的这两类不同化合物发生相互作用,相应地影响了酶的催化活性。还发现Co(Ⅱ)(His)n比CoCl2与酶相互作用更强、更快,Co(Ⅱ)(His)n中的Co(Ⅱ)更易进入酶中,更影响了酶的催化活性。  相似文献   

3.
采用VIS和 ICP及酶活性测定等方法,研究铜锌超氧歧化酶(Cu2Zn2SOD)与组氨酸钴(Ⅱ)[Co(His)n] 的直接相互作用及外加组氨酸钴(Ⅱ)、磷酸盐对此类相互作用的影响。结果发现,水溶液中原酶活性中心的Cu(Ⅱ)和Zn(Ⅱ)离子可被外加的组氨酸钴(Ⅱ)部分诱导、交换出来,而Co(His)n 中的Co(Ⅱ)进入酶的活性中心,形成“Co-SOD”酶衍生物各组分,并相应影响了酶的催化活性。与此同时,外加组氨酸钴(Ⅱ)及磷酸盐对此类相互作用有着重要的影响  相似文献   

4.
采用VIS和ICP及酶活性测定等方法,研究铜锌超氧歧化酶(Cu2ZnSOD)与组氨酸钴(Ⅱ)〖Co(His)〗的直接相互作用及外加组氨酸钴(Ⅱ)、磷酸盐对此类相互作用的影响。结果发现,水溶液中原酶活性中心Cu(Ⅱ)和Zn(Ⅱ)离子可被外加的组氨酸钴(Ⅱ)部分诱导,交换出来,而Co(His)。中的Co(Ⅱ)进入酶的活性中心,形成“Co-SOD”酶衍生物各组分,并相应影响了酶的催化活性。与此同时,外加  相似文献   

5.
铜锌超氧化物歧化酶与色氨酸钴(Ⅱ)的相互作用   总被引:1,自引:1,他引:0  
采用VIS、ICP及酶活性测定等方法,研究铜锌超氧歧化酶(Cu2Zn2SOD)与色氨酸钴(Ⅱ)(Co(Trp)^n)的直接相互作用以及外加色氨酸钴(Ⅱ)的量、溶液pH值对此类相互作用的影响。结果发现:在水溶液中原酶活性中心处的Zn(Ⅱ)离子可被外加的色氨酸钴(Ⅱ)部分诱导、交换出来,而溶液中外加的Co(Trp)^n中的Co(Ⅱ进入酶的活性中心,形成“Co-SOD”酶衍生物,并相应影响了酶的催化活性  相似文献   

6.
采用VIS,ICP 及酶活性测定等方法,研究铜锌超氧歧化酶(Cu2Zn2SOD)与组氨酸钴(Ⅱ) (Co(His)n ) 直接相互作用时溶液pH值、作用时间对此类相互作用的影响。结果发现,溶液的pH值越高,作用时间越长,越有利于此类相互作用的进行  相似文献   

7.
采用VIS,ICP及酶活性测定等方法,研究铜锌超氧歧化酶(Cu-Zn2SOD)与组氨酸钴(Ⅱ)(Co(HiS)。直接相互作用时溶液pH值、作用时间对此类相互作用的影响。结果发现,溶液的pH值越高,作用时间越长,超有利于类此相互作用的进行。  相似文献   

8.
我们首次发现的铜锌超氧歧化酶(Cu2Zn2SOD)与氨基酸等发生直接相互作用的现象,是一种前人未研究过的重要的生化新现象。在此新发现的基础上,本文用ICP,VIS,NMR和酶活性测定方法,又从不同角度拓展研究了Cu2Zn2SOD酶与两类不同化合物,  相似文献   

9.
不同金属离子与色氨酸作用的荧光光谱研究   总被引:2,自引:0,他引:2  
研究了不同金属离子对色氨酸的荧光强度的影响。结果表明,在一定条件下当达到一定浓度时,Cu(Ⅱ),Fe(Ⅲ),Mo(Ⅵ)对色氨酸的荧光有猝灭作用,而此时Zn(Ⅱ),Mn(Ⅱ),Cr(Ⅲ),Co(Ⅱ),Ca(Ⅱ)和Na(Ⅰ)则对色氨酸的荧光几乎没有影响。  相似文献   

10.
对四种单核钴化合物Co(mpo)_3·CH_3CN(Ⅰ),CO(mpo)_2PBu_3(D),Co(mpo)_2Py(Ⅲ)和Co(mpo)_2Py_2(Ⅳ)的 ̄1HNMR作了研究,讨论了它们的分子结构与磁性及电子结构之间的关系,确认化合物(Ⅱ)在DMSO溶液中被解离为Co(mpo)_2和PBu_3,而其它三种化合物仍保留着固态结构。  相似文献   

11.
合成了4种新的糖胺 金属配合物,分别为[Ni(HL) (H2 O) 2 ]2 Cl2 ·CH3OH·2H2 O ,[Cu(HL) ]2 Cl2 ·CH3CH2 OH·3H2 O ,[Zn(HL) ]2 Cl2 ·H2 O ,[Co(HL) (H2 O) (OH) ]2 Cl2 ·CH3OH·2H2 O (HLN ,N′ 二βD 葡萄糖基乙二胺) ,并用元素分析、红外、紫外、核磁共振氢谱对其结构进行了表征。结果表明,Ni(Ⅱ) ,Co(Ⅲ)配合物为八面体构型,而Cu(Ⅱ) ,Zn(Ⅱ)配合物为四面体构型。最后研究了其对对硝基苯吡啶甲酸酯(PNPP)催化水解的催化速率常数。  相似文献   

12.
Free radical concentration and theirg-values in humic acids (HA) isolated from various sources were studied by quantitative EPR technique. EPR data for HA formed during composting and natural humification processes occurring in soil, peat and brown coal are given. In more detail the EPR data were analyzed for brown coal HA under carbonization, air oxidation (150°C) as well as metal uptake (Ca(II), Zn(II), Cd(II), Hg(II), Co(II), Ni(II) and Cu(II)) and NO2 reaction. Two groups of metal complexes were distinguished on the basis of their interaction with free radicals in HA. Ca(II), Zn(II), Cd(II) and Hg(II) ions increase free radical concentration, while Co(II), Ni(II) and Cu(II) ions quench the radicals compared to the raw HA. This phenomenon can be explained either by the strong interaction of the metal ions with active centres responsible for the quinone-hydroquinone-semiquinone equilibria, and/or by the antiferromagnetic interaction between radical spins and metal d orbitals. Gaseous ammonia was found to be a very useful base easily penetrating the solid matrix of HA and strongly influencing the equilibria. β-Diketone groups present in HA react with NO2 yielding iminoxy radicals. In the HA-metal complexes these structural units are engaged in metal coordination which lowers effectiveness of the iminoxyl synthesis.  相似文献   

13.
Liu N  Jia CM  Zhang Q  Yuan WB  Dai XQ  Wu JB 《光谱学与光谱分析》2010,30(12):3343-3346
合成了新型仲胺类配体L(N,N’-二(4-甲基苄基)乙二胺)及其四种过渡金属的硝酸盐配合物,[ML2(H2O)2]2+.2NO3-(M=CuⅡ,CoⅡ,NiⅡ,ZnⅡ),利用元素分析、红外、1H NMR等对其结构进行了表征,其中用X-ray单晶衍射解析了Cu-L单晶结构,为波谱分析推测的分子结构进行了验证。通过紫外、荧光光谱研究了该四种金属配合物与小牛胸腺DNA的相互作用,结果表明配合物与DNA的作用方式均为静电结合,Cu-L,Co-L,Ni-L,Zn-L与DNA的结合常数分别为:1.67×103,2.5×103,1.35×103和9.85×102。  相似文献   

14.
Chemo-sensor technology demands to design a single, preconcentrator based sensing system having higher sensitivity, sufficient selectivity and efficient removal of metal ions with simple operating and recognition methodology. Here we effectively deliberated Ce doped SnO2 nanoparticles based sensing system which can be exploited for the recognition and extraction of Co(II) ions in a single step by strong interaction between Ce doped SnO2 nanoparticles and Co(II). The sensing ability of Ce doped SnO2 nanoparticles were deliberated for a selective removal of cobalt using inductively coupled plasma-optical emission spectrometry. The sensing ability of Ce doped SnO2 is studied for various metal ions, such as Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Ni(II) and Zn(II) but the designed sensor was most selective toward Co(II) which was 5000 time more sensitive to Co(II) rather than different interfering metal ions. In addition, the desorption study for regeneration of Ce doped SnO2 nanoparticles was carried out. This novel approach provides a new route for simultaneous detection and removal of Co(II) in a single step and can be a time and cost alternative tool for environmental safety.  相似文献   

15.
The DNA binding and photocleavage specificities of the Zn(II), Cu(II), Co(III), Mn(III) complexes of 5,10,15-tris(1-methylpyridinium-4-yl)-20-(4-propionoxyphenyl)porphyrin have been studied by using a combination of absorption, fluorescence titration, surface-enhanced Raman spectroscopy (SERS), induced circular dichroism (ICD) spectroscopy, thermal DNA denaturation as well as gel electrophoresis experiment. It is found that Cu(II) porphyrin has comparable binding ability with the free base porphyrin while the axial-coordinated Zn(II), Co(III), and Mn(III) porphyrins have lower Kb because of the molecular steric hindrance. However, those metalloporphyrins with lower Kb have similar DNA cleavage efficiencies with the free base porphyrin. This could be best understood by the enhancement of the 1O2 productivity which may also result from the steric hindrance of the axial-coordinated metalloporphyrins.  相似文献   

16.
氨基酰化酶与Cu(Ⅱ)相互作用的谱学研究   总被引:2,自引:1,他引:1  
通过顺磁共振法、可见光谱法及酶活性测量研究从猪肾中提纯的氨基酰化酶(Aminoacylase,简称ACY)在pH4.0条件下与外加的Cu(Ⅱ)离子存在直接相互作用。结果发现:外加Cu(Ⅱ)离子进入ACY活性中心位点,取代了活性中心位点的Zn(Ⅱ),使酶活性下降。随着pH变化生成的两种构型酶衍生物在溶液中可相互转化。  相似文献   

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