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61.
Three strains of Mn-oxidizing fungi were isolated from manganese-rich aquatic environments: sediment in a stream (Komanoyu)
in Mori-machi and inflow to an artificial wetland in Kaminokuni-cho, Hokkaido, Japan. The characteristics of each strain were
then established. Genetic analysis based on the ribosomal RNA (rRNA) gene was performed to clarify their classification. The
sequences of the 18S rRNA and internal transcribed spacer (ITS1)-5.8S rRNA-ITS2 genes showed that all three strains are Ascomycetes.
Based on its morphology, it seems probable that the KY-1 strain from Mori-machi belongs to the genus Phoma or Ampelomyces. The phylogenetic analysis indicates that this strain belongs to Phoma rather than Ampelomyces. Morphological identification of WL-1 and WL-2 strains from Kaminokuni-cho was impossible because of the lack of a sexual
stage and specific organs. Phylogenetic analysis of the sequence in the ITS1-5.8S rRNA-ITS2 gene suggests that the WL-1 strain
corresponds to Paraconyothyrium sporulosum and that WL-2 also belongs to the genus Paraconiothyrium. Because the ability to oxidize Mn has not been evaluated for most species of Phoma or Paraconiothyrium (Coniothyrium), further study is needed to confirm the status of these three strains. 相似文献
62.
X-ray crystallographic analysis of Na5[Mn(l-tart)2] · 12H2O demonstrated that Mn(III) ion has two tridentate l-tartrates of which two deprotonated hydroxo groups and one carboxylate are coordinated in contrast to the previously proposed structure with two didentate tartrates and two coordinated water. The tetragonally distorted octahedron due to the Jahn-Teller effect was discussed in relation with the large splitting components for the UV-Vis and circular dichroism (CD) spectra in the d-d transition in the solid. The significant difference in the UV-Vis and CD spectra between the solid and the solution suggests that the tridentate coordination of the tartrate in the solid complex changes to the didentate one in the solution. 相似文献
63.
Quantitative analysis of DNA-porphyrin interactions 总被引:1,自引:0,他引:1
The binding of manganese(III)-tetra(4-N-methylpyridyl)porphyrin (MnTMpyP) with synthetic poly(dA-dT)2, poly(dI-dC)2, and poly(dG-dC)2 DNAs as well as calf thymus (CT) DNA has been quantitatively studied in detail using induced CD (circular dichroism) spectroscopy in the Soret absorption band. The CD spectra, which changed greatly depending on the porphyrin to DNA base-pair molar ratio (r), were normalized with respect to DNA concentration and deconvoluted. Three independent component binding modes (named mode 1, 2, and 3 in the order of increasing r values) were identified, which successfully simulated the observed CD spectra with negligibly small residuals for a wide range of r values. In the case of poly(dA-dT)2, poly (dI-dC)2, and CT DNA, all the three modes appeared, whereas in the case of poly(dG-dC)2 DNA, only modes 1 and 3 appeared in the r range studied. The r dependence of each binding mode, i.e., its relative affinity toward DNA, has been revealed by this analysis. Mode 1, which appeared as a single binding mode at very low r values (r < or = ca. 0.05), was inhibited by the addition of methyl green, a drug that preferentially binds to the major groove of poly (dA-dT)2 DNA. Berenil, a known minor groove binder to poly(dA-dT)2 or poly(dI-dC)2 DNA, inhibited modes 2 and 3. From these inhibition experiments as well as comparison of the component spectra for DNAs of different sequence, a binding site on DNA was proposed for each component binding mode. The number of DNA base pairs covered by a single molecule of porphyrin was estimated. 相似文献
64.
65.
66.
A. V. Vasil’ev V. I. Ivakhnenko S. A. Khotimchenko V. V. Korzh 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2008,2(3):306-310
Studies of Km for glutathione peroxidase (GPx) and activities of superoxide dismutase and GPx were carried out in liver and erythrocytes of rats kept on either the normal semisynthetic diet or a high-fat diet with increased content of Cu, Zn, Mn, and Se. The diet containing microelement additions caused the increase in TBH affinity of liver and erythrocyte GPx, as well as the decrease of liver SOD observed on the 14th day of the treatment of rats with the high-fat diet with additional increase of Cu, Zn, Mn, and Se. 相似文献
67.
Six-coordinate low-spin iron(III) porphyrinates adopt either common (d(xy))(2)(d(xz),d(yz))(3) or less common (d(xz),d(yz))(4)(d(xy))(1) ground state. In this review article, three major factors that affect the electronic ground state have been examined. They are (i) nature of the axial ligand, (ii) electronic effect of peripheral substituents, and (iii) deformation of porphyrin ring. On the basis of the (1)H NMR, (13)C NMR, and EPR data, it is now clear that (i) the axial ligands with low-lying pi* orbitals such as tert-butylisocyanide and 4-cyanopyridine, (ii) the electron donating groups at the meso-carbon atoms, and (iii) the ruffled deformation of porphyrin ring stabilize the (d(xz),d(yz))(4)(d(xy))(1) ground state. By manipulating these factors, we are able to prepare various low-spin iron(III) porphyrinates with unusual electronic structures such as bis(imidazole) complexes with the (d(xz),d(yz))(4)(d(xy))(1) ground state or bis(tert-butylisocyanide) complexes with the (d(xy))(2)(d(xz),d(yz))(3) ground state; bis(imidazole) and bis(tert-butylisocyanide) complexes usually adopt the (d(xy))(2)(d(xz),d(yz))(3) and (d(xz),d(yz))(4)(d(xy))(1) ground state, respectively. 相似文献
68.
Excessive Zn but normal Cu and Mg in the staple food consumed by the people of Chandigarh (Union territory and capital of
Punjab and Haryana States of India) has been considered to be the major risk factor for the prevalence of obesity (33.15%)
and obesity-related diseases in this region. Therefore, in the present investigations, in obesity-related diseases, the status
of these minerals was estimated in their tissues, including hair, nails, and blood serum and urine, and compared with those
of normal subjects. They were grouped as: normal subjects in control Group A, middle-aged diabetics in Group DM, older diabetics in Group DO, and diabetics with osteoarthritis in Group D+ OA, osteoarthritis in Group OA and rheumatoid arthritis in Group RA, respectively.
The results evaluated in the order as: hair Zn, group D+OA>DM>OA>A (control)>RA>DO (p < 0.001); hair Cu, group A (control)>DM>OA>D+OA>DO>RA (p < 0.001); hair Mg, group A (control)>DM>OA>D+OA>RA>DO (p < 0.001, 0.01); hair Mn, group A (control)>RA>OA>D-OA>DM>DO (p < 0.001); nail Zn, group DM>D+OA>OA>A (control)>RA>DO (p < 0.001, 0.05); nail Cu, group A (control)>OA>DM>D+OA>RA>DO (p < 0.001); nail Mg, group A (control)>OA>DM>DO>D+OA >RA (p < 0.001); nail Mn, group A (control) >RA>OA>D+OA>DM>DO (p < 0.01); urine Zn, group DO>DM>D+OA>A (control)>RA>OA (p < 0.01); urine Cu, group RA>D+OA>DO>OA> DM>A (control) (p<0.001); urine Mg, group RA>OA>D+OA>DO>DM>A (control; p < 0.001); urine Mn, group DO>DM>OA>D+OA>RA>A (control; p < 0.001), respectively. The analysis of the mineral status in serum of diabetics further showed their highly significant
rise from lower mean age subgroup to higher mean age subgroup than their control counter parts (p < 0.001, 0.01, and 0.05) with coincident deficiencies of Cu, Mg, and Mn in their tissues. This study would be helpful considering
the status of minerals in these obesity-related diseases depending on the choice of the food consumed to improve the quality
of life and prognosis for the diseases. 相似文献
69.
Júlio S. Rebouças Ivan Spasojević Ines Batinić-Haberle 《Journal of biological inorganic chemistry》2008,13(2):289-302
Superoxide is involved in a plethora of pathological and physiological processes via oxidative stress and/or signal transduction pathways. Superoxide dismutase (SOD) mimics have, thus, been actively sought for clinical and mechanistic purposes. Manganese(III) 5,10,15,20-tetrakis(4-benzoic acid)porphyrin (MnTBAP) is one of the most intensely explored "SOD mimics" in biology and medicine. However, we show here that this claimed SOD activity of MnTBAP in aqueous media is not corroborated by comprehensive structure-activity relationship studies for a wide set of Mn porphyrins and that MnTBAP from usual commercial sources contains different amounts of noninnocent trace impurities (Mn clusters), which inhibited xanthine oxidase and had SOD activity in their own right. In addition, the preparation and thorough characterization of a high-purity MnTBAP is presented for the first time and confirmed that pure MnTBAP has no SOD activity in aqueous medium. These findings call for an assessment of the relevance and suitability of using MnTBAP (or its impurities) as a mechanistic probe and antioxidant therapeutic; conclusions on the physiological and pathological role of superoxide derived from studies using MnTBAP of uncertain purity should be examined judiciously. An unequivocal distinction between the biological effects due to MnTBAP and that of its impurities can only be unambiguously made if a pure sample is/was used. This work also illustrates the contribution of fundamental structure-activity relationship studies not only for drug design and optimization, but also as a "watchdog" mechanism for checking/spotting eventual incongruence of drug activity in chemical and biological settings. 相似文献
70.
Parihar MS Parihar A Villamena FA Vaccaro PS Ghafourifar P 《Biochemical and biophysical research communications》2008,367(4):761-767
We recently demonstrated that mitochondrial nitric oxide synthase (mtNOS) functionally couples with mitochondrial respiratory chain complex I to produce nitric oxide [M.S. Parihar, R.R. Nazarewicz, E. Kincaid, U. Bringold, P. Ghafourifar, Association of mitochondrial nitric oxide synthase activity with respiratory chain complex I, Biochem. Biophys. Res. Commun. 366 (2008) 23-28] [1]. The present report shows that inactivation of complex I leads mtNOS to become pro-oxidative. Our findings suggest a crucial role for mtNOS in oxidative stress caused by mitochondrial complex I inactivation. 相似文献