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71.
Chiaiese P Palomba F Galante C Esposito S De Biasi MG Filippone E 《International journal of phytoremediation》2012,14(9):835-844
A biotechnological approach was applied to reduce phenol content in olive mill wastewaters by transgenic tobacco plants. The cDNA laccase of poxC gene from Pleurotus ostreatus, carrying its own signal peptide for extracellular secretion, was transferred into the Nicotiana tabacum genome. Transgenic tobacco plants were obtained and the recombinant enzyme was secreted into the rhizosphere by the plant root apparatus, confirming the ability of the plant machinery to recognize the fungal POXC peptide signal leader appropriately as secretory tag. Total laccase activity assayed by ABTS in transgenic lines increased sharply compared to control plants. Moreover, plants cultivated in a hydroponic solution with the addition of olive mill wastewaters were able to reduce the total phenol content up to 70%. 相似文献
72.
73.
Membrane topology of ATP synthase from bovine heart mitochondria and Escherichia coli 总被引:1,自引:0,他引:1
C Montecucco F Dabbeni-Sala P Friedl Y M Galante 《European journal of biochemistry》1983,132(1):189-194
The polypeptides exposed to lipids in the membranous F0 sector of the mitochondrial and Escherichia coli ATP synthases were labelled with radioactive photoreactive lipids. Highly resolving gel electrophoretic conditions were used in order to separate all the eighteen components forming the bovine heart mitochondrial enzyme. The hydrophobic labelling was performed on fully active and inhibitor-sensitive ATP synthases. In the mitochondrial enzyme prepared according to Serrano et al. (1976) [J. Biol. Chem. 251, 2453-2461] seven polypeptides of Mr 30500; 11500; 10500; 10000; 9500; 8500 and 4500 were labelled. The major amount of radioactivity was associated with the 30500-Mr component, which is thought to be the adenine nucleotide carrier. In the preparation of Galante et al., (1979) which almost completely lacks this component [J. Biol. Chem. 254, 12372-12378] nine polypeptides of Mr 25000; 21000; 11500; 10500; 10000; 9500; 9200; 8500 and 4500 were labelled. In the ATPase synthase from E. coli the major amount of labelling was associated with subunit b and only a minor portion with subunit c. 相似文献
74.
Interaction of rhodanese with mitochondrial NADH dehydrogenase 总被引:2,自引:0,他引:2
NADH dehydrogenase is an iron-sulfur flavoprotein which is isolated and purified from Complex I (mitochondrial NADH: ubiquinone oxidoreductase) by resolution with NaClO4. The activity of the enzyme (followed as NADH: 2-methylnaphthoquinone oxidoreductase) increases linearly with protein concentration (in the range between 0.2 and 1.0 mg/ml) and decreases with aging upon incubation on ice. In the present work a good correlation was found between enzymic activity and labile sulfide content, at least within the limits of sensitivity of the assays employed. Rhodanese (thiosulfate: cyanide sulfurtransferase (EC 2.8.1.1) purified from bovine liver mitochondria was shown to restore, in the presence of thiosulfate, the activity of the partly inactivated NADH dehydrogenase. Concomitantly, sulfur was transferred from thiosulfate to the flavoprotein and incorporated as acid-labile sulfide. Rhodanese-mediated sulfide transfer was directly demonstrated when the reactivation of NADH dehydrogenase was performed in the presence of radioactive thiosulfate (labeled in the outer sulfur) and the 35S-loaded flavoprotein was re-isolated by gel filtration chromatography. The results indicated that the [35S]sulfide was inserted in NADH dehydrogenase and appeared to constitute the structural basis for the increase in enzymic activity. 相似文献
75.
Bilayer thickness and enzymatic activity in the mitochondrial cytochrome c oxidase and ATPase complex 总被引:1,自引:0,他引:1
C Montecucco G A Smith F Dabbeni-sala A Johannsson Y M Galante R Bisson 《FEBS letters》1982,144(1):145-148
The antigenic cross-reactivity between purified chick, eel and mouse electrolectins (endogenous β-D-galactoside specifc lectins) have been studied using a solid phase radioimmunoassay. The immune serum raised against the eel electrolectin crossreacts both with the chick and the mouse electrolectins, while the anti-chick electrolectin anti-serum recognizes only the eel but not the mouse electrolectin. These findings are analyzed in terms of the phylogenetic distance separating the species considered; they suggest that electrolectins fulfil a fundamental biological function. 相似文献
76.
Iron-sulfur N-1 clusters studied in NADH-ubiquinone oxidoreductase and in soluble NADH dehydrogenase
Two N-1 type iron-sulfur clusters in NADH-ubiquinone oxidoreductase (Complex I, EC 1.6.5.3) were potentiometrically resolved: one was titrated as a component with a midpoint oxidation-reduction potential of -335 mV at pH 8.0, and with an n-value equal to one; the other as an extremely low midpoint potential component (Em 8.0 less than -500 mV). These two clusters are tentatively assigned to N-1b and N-1a, respectively. Cluster N-1b is completely reducible with NADH and has a spin concentration of about 0.8/FMN. Its EPR spectrum can be simulated as a single rhombic component with principal g values of 2.019, 1.937, and 1.922, which correspond to the Center 1 reported earlier by Orme-Johnson, N. R., Hansen, R. E., and Beinert, H. (1974) J. Biol. Chem. 249, 1922-1927. At extremely low oxidation-reduction potentials (less than -450 mV), additional EPR signals emerge with apparent g values of gz = 2.03, gy = 1.95, and gx = 1.91, which we assign to cluster N-1a. It is difficult, however, to simulate the detailed spectral line shape of this component as a single rhombic component, suggesting some degree of protein modification or interaction with a neighboring oxidation-reduction component. EPR spectra of soluble NADH dehydrogenase, containing 5-6 g atoms of non-heme iron and 5-6 mol of acid-labile sulfide/mol of FMN, were examined. Signals from at least two iron-sulfur species could be distinguished in the NADH-reduced form: one of an N-1b type spectrum; the other of a spectrum with g values of 2.045, 1.95, and 1.87 (total of about 0.5 spin equivalents/FMN). This is the first example of an N-1 type signal detected in isolated soluble NADH dehydrogenase. 相似文献
77.
The antigenic properties of purified glycinin subunits were studied using antibodies prepared against them. Antisera against native glycinin did not react with the isolated subunits, and antibodies prepared against the purified subunits were not active against native glycinin. When native glycinin -was denatured, the antiglycinin immunoglobulins lost their ability to react with it, although the denatured complex was then recognized by antibodies against the purified subunits. Substantial structural rearrangement apparently occurred when the native complex was denatured and disaggregated. Acidic polypeptides A1a, A1b, and A2 had similar determinants as judged by their reactions against A1a and A1a antisera. The reaction of the A3 polypeptides with these antibodies was of lower intensity and in each case clear spurs of cross-reactivity were visible. No cross-reaction was detected between polypeptide A4 and either anti-A1a or A2. Anti-A3 antibodies reacted with each of the acidic polypeptides of glycinin, and distinct spurs of cross-reactivity were observed between A3 vs A1a, A3 vs A2, and A3 vs A4. B1 Antisera developed a reaction of identity between basic polypeptides B1 and B2, but reacted very weakly with B3 and B4. The acidic and basic polypeptides of glycinin were immunologically unrelated. The results demonstrated that immunological tests would successfully differentiate some members of the family of acidic subunits, and other immunoglobulins would discriminate between members of the family of basic subunits. 相似文献
78.
S Cecchini M Confortini L Bonardi G Cipparrone L Galante A Iossa S Ciatto 《Acta cytologica》1990,34(6):781-784
The association between "nonclassic" cytologic signs of condyloma and human papillomavirus (HPV) infection in women with negative Papanicolaou smears was analyzed via a case-control study. The cytologic signs considered were mild koilocytosis, mild dyskeratosis, binucleation or multinucleation, cleared cytoplasm and nuclear hyperchromatism. The Papanicolaou smears of 166 cases that showed colposcopic and histologic evidence of HPV infection (but whose smears lacked the classic cytologic signs of condyloma) and 166 controls that were negative colposcopically were randomly admixed and blindly reviewed by a panel of cytologists. A significant association to HPV infection was observed for all of the nonclassic signs studied, but multivariate analysis showed a weakly independent association only for mild koilocytosis. The sensitivity (0.46) and the specificity (0.87) of these nonclassic signs were not satisfactory. The utility of selecting women with negative Papanicolaou smears for colposcopy on the basis of these signs is discussed. 相似文献
79.
80.
Little is known about the molecular mechanisms underlying sleep. We show the induction of key regulatory proteins in a cellular protective pathway, the unfolded protein response (UPR), following 6 h of induced wakefulness. Using C57/B6 male mice maintained on a 12:12 light/dark cycle, we examined, in cerebral cortex, the effect of different durations of prolonged wakefulness (0, 3, 6, 9 and 12 h) from the beginning of the lights-on inactivity period, on the protein expression of BiP/GRP78, a chaperone and classical UPR marker. BiP/GRP78 expression is increased with increasing durations of sleep deprivation (6, 9 and 12 h). There is no change in BiP/GRP78 levels in handling control experiments carried out during the lights-off period. PERK, the transmembrane kinase responsible for attenuating protein synthesis, which is negatively regulated by binding to BiP/GRP78, is activated by dissociation from BiP/GRP78 and by autophosphorylation. There is phosphorylation of the elongation initiation factor 2alpha and alteration in ribosomal function. These changes are first observed after 6 h of induced wakefulness. Thus, prolonging wakefulness beyond a certain duration induces the UPR indicating a physiological limit to wakefulness. 相似文献