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241.
P. Bertrand M. Bruschi M. Denis J.P. Gayda F. Manca 《Biochemical and biophysical research communications》1982,106(3):756-760
Cytochrome c553 is a monohaemic c type cytochrome isolated from the sulfate reducing bacteria ,. Its midpoint potential value, determined by optical, EPR and polarographic studies is significantly lower than the midpoint potentials reported for other monohaemic cytochromes c (+ 10 mV instead of + 290 mV). In an attempt to study correlations between amino acid sequence, haem iron coordination and haem exposure in cytochromes c, cytochrome c553 is compared with mitochondrial and bacterial c type cytochromes. 相似文献
242.
Nora M. Urquiza Silvia G. Manca María A. Moyano Raquel Arrieta Dellmans Luis Lezama Teófilo Rojo Luciana G. Naso Patricia A. M. Williams Evelina G. Ferrer 《Biometals》2010,23(2):255-264
Methimazole (MeimzH) is an anti-thyroid drug and the first choice for patients with Grave’s disease. Two new copper(II) complexes of this drug:
[Cu(MeimzH)2(NO3)2].0.5H2O and [Cu(MeimzH)2(H2O)2](NO3)2·H2O were synthesized and characterized by elemental analysis, dissolution behavior, thermogravimetric analysis and UV-vis, diffuse
reflectance, FTIR and EPR spectroscopies. As it is known that copper(II) cation can act as an inhibitor of alkaline phosphatase
(ALP), the inhibitory effect of methimazole and its copper(II) complexes on ALP activity has also been investigated. 相似文献
243.
244.
In this report we describe the complete sequence of the mtDNA genome of Ammotragus lervia (Barbary sheep or aoudad) as obtained by PCR and sequencing with primer walking using flanking sequences. The molecule is 16,530 base pairs in length, resulting similar to those of goat and sheep. The genome organization matches to those of other mammalian mitochondrial genomes. The phylogenetic position of the Ammotragus relative to twelve other mammalian species was assessed based on protein-coding sequences. A goat-aoudad split of 9.9-8.9 MYBP has been estimated, whereas the divergence ancestor/caprines was dated at 12.1-10.8 MYBP. 相似文献
245.
A Di Luccia L Iannibelli E Addato B Masala L Manca L Ferrara 《Comparative biochemistry and physiology. B, Comparative biochemistry》1991,99(4):887-892
1. Hemoglobin (Hb) of the river buffalo (Bubalus bubalis L.) was studied by employing isoelectric focusing (IEF) in the 6.7-7.7 pH range and by IEF in ultra-narrow immobilized pH gradient (IPG) 7.1-7.5. 2. Three Hb BB phenotypes were identified which were characterized by sets of two or four Hbs with different isoelectric points. 3. These type were called BB, BsBs and BBs, the Bs phenotype showing Hbs with slightly slower mobility. 4. Analysis of constituent globin chains by acid urea polyacrylamide gel electrophoresis in the presence of Triton X-100, provided clear evidence of a novel polymorphism at the beta-globin level. 5. Titration curves of beta-globins from heterozygous Hb BBs indicated a single curve thus suggesting the absence of a net charge in all the pH field. 6. A neutral-to-neutral amino acid replacement probably differentiates the two beta-globins. 相似文献
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247.
The electrochemical reduction of a series of copper(II) complexes with 1,10-o-phenanthrolines, namely the 1:1 and 1:2 metal:ligand complexes with 2,9-dimethylphenanthroline, 4,7-dimethylphenanthroline and unsubstituted phenanthroline, respectively, has been studied in N,N-dimethylformamide using platinum electrodes. As to the 1:2 complexes, the effect of the presence of substituents with different electronic and steric effects on the phenanthroline ligands has been studied with the aim of rationalizing the different values of the standard potentials which have been measured. Furthermore, the possibility of electrogenerating neutral species, with a formally zerovalent copper centre, exhibiting different stability depending on the nature of the ligands, has been ascertained. In out solvent medium, 1:1 complexes have been found to be in equilibrium with the corresponding 1:2 complexes. A scheme for the reduction of solutions of these compounds, including the different equilibria associated to the electrode charge transfers, has been outlined. 相似文献