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31.
Angela Pennacchio Assunta Giordano Biagio Pucci Mosè Rossi Carlo A. Raia 《Extremophiles : life under extreme conditions》2010,14(2):193-204
The gene encoding a novel alcohol dehydrogenase that belongs to the short-chain dehydrogenases/reductases (SDRs) superfamily
was identified in the aerobic thermoacidophilic crenarchaeon Sulfolobus acidocaldarius strain DSM 639. The saadh gene was heterologously overexpressed in Escherichia coli, and the protein (SaADH) was purified to homogeneity and characterized. SaADH is a tetrameric enzyme consisting of identical
28,978-Da subunits, each composed of 264 amino acids. The enzyme has remarkable thermophilicity and thermal stability, displaying
activity at temperatures up to 75°C and a 30-min half-inactivation temperature of ~90°C, and shows good tolerance to common
organic solvents. SaADH has a strict requirement for NAD(H) as the coenzyme, and displays a preference for the reduction of
alicyclic, bicyclic and aromatic ketones and α-keto esters, but is poorly active on aliphatic, cyclic and aromatic alcohols,
and shows no activity on aldehydes. The enzyme catalyses the reduction of α-methyl and α-ethyl benzoylformate, and methyl
o-chlorobenzoylformate with 100% conversion to methyl (S)-mandelate [17% enantiomeric excess (ee)], ethyl (R)-mandelate (50% ee), and methyl (R)-o-chloromandelate (72% ee), respectively, with an efficient in situ NADH-recycling system which involves glucose and a thermophilic
glucose dehydrogenase. This study provides further evidence supporting the critical role of the D37 residue in discriminating
NAD(H) from NAD(P)H in members of the SDR superfamily. 相似文献
32.
Deiana M Incani A Rosa A Atzeri A Loru D Cabboi B Paola Melis M Lucas R Morales JC Assunta Dessì M 《Chemico-biological interactions》2011,(3):232-239
Hydroxytyrosol (2-(3′,4′-dihydroxyphenyl)ethanol; HT), the most active ortho-diphenolic compound, present either in free or esterified form in extravirgin olive oil, is extensively metabolized in vivo mainly to O-methylated, O-sulfated and glucuronide metabolites. We investigated the capacity of three glucuronide metabolites of HT, 3′-O-β-d-glucuronide and 4′-O-β-d-glucuronide derivatives and 2-(3′,4′-dihydroxyphenyl)ethanol-1-O-β-d-glucuronide, in comparison with the parent compound, to inhibit H2O2 induced oxidative damage and cell death in LLC-PK1 cells, a porcine kidney epithelial cell line. H2O2 treatment exerted a toxic effect inducing cell death, interacting selectively within the pro-death extracellular-signal relate kinase (ERK 1/2) and the pro-survival Akt/PKB signaling pathways. It also produced direct oxidative damage initiating the membrane lipid peroxidation process. None of the tested glucuronides exhibited any protection against the loss in renal cell viability. They also failed to prevent the changes in the phosphorylation states of ERK and Akt, probably reflecting their inability to enter the cells, while HT was highly effective. Notably, pretreatment with glucuronides exerted a protective effect at the highest concentration tested against membrane oxidative damage, comparable to that of HT: the formation of malondialdehyde, fatty acid hydroperoxides and 7-ketocholesterol was significantly inhibited. 相似文献
33.
Ute Distler Michael J. Schmeisser Assunta Pelosi Dominik Reim Jörg Kuharev Roland Weiczner Jan Baumgart Tobias M. Boeckers Robert Nitsch Stefan Tenzer 《Proteomics》2014,14(21-22):2607-2613
Located at neuronal terminals, the postsynaptic density (PSD) is a highly complex network of cytoskeletal scaffolding and signaling proteins responsible for the transduction and modulation of glutamatergic signaling between neurons. Using ion‐mobility enhanced data‐independent label‐free LC‐MS/MS, we established a reference proteome of crude synaptosomes, synaptic junctions, and PSD derived from mouse hippocampus including TOP3‐based absolute quantification values for identified proteins. The final dataset across all fractions comprised 49 491 peptides corresponding to 4558 protein groups. Of these, 2102 protein groups were identified in highly purified PSD in at least two biological replicates. Identified proteins play pivotal roles in neurological and synaptic processes providing a rich resource for studies on hippocampal PSD function as well as on the pathogenesis of neuropsychiatric disorders. All MS data have been deposited in the ProteomeXchange with identifier PXD000590 ( http://proteomecentral.proteomexchange.org/dataset/PXD000590 ). 相似文献
34.
Rosalba Parenti Venera Cardile Adriana Carol Eleonora Graziano Carmela Parenti Assunta Venuti Maria Paola Bertuccio Debora Lo Furno Gaetano Magro 《PloS one》2014,9(12)
Wilms’ tumor gene 1 (WT1) plays complex roles in tumorigenesis, acting as tumor suppressor gene or an oncogene depending on the cellular context. WT1 expression has been variably reported in both benign and malignant peripheral nerve sheath tumors (MPNSTs) by means of immunohistochemistry. The aim of the present study was to characterize its potential pathogenetic role in these relatively uncommon malignant tumors. Firstly, immunohistochemical analyses in MPNST sNF96.2 cell line showed strong WT1 staining in nuclear and perinuclear areas of neoplastic cells. Thus, we investigated the effects of silencing WT1 by RNA interference. Through Western Blot analysis and proliferation assay we found that WT1 knockdown leads to the reduction of cell growth in a time- and dose-dependent manner. siWT1 inhibited proliferation of sNF96.2 cell lines likely by influencing cell cycle progression through a decrease in the protein levels of cyclin D1 and inhibition of Akt phosphorylation compared to the control cells. These results indicate that WT1 knockdown attenuates the biological behavior of MPNST cells by decreasing Akt activity, demonstrating that WT1 is involved in the development and progression of MPNSTs. Thus, WT1 is suggested to serve as a potential therapeutic target for MPNSTs. 相似文献
35.
Gabriele Giacomo Schiattarella Fabio Cattaneo Gianluigi Pironti Fabio Magliulo Giuseppe Carotenuto Marinella Pirozzi Roman Polishchuk Domenica Borzacchiello Roberta Paolillo Marco Oliveti Nicola Boccella Marisa Avvedimento Maria Sepe Giuseppe Gargiulo Assunta Lombardi Rosa Anna Busiello Bruno Trimarco Giovanni Esposito Antonio Feliciello Cinzia Perrino 《PloS one》2016,11(7)
36.
By controlling the subcellular localization of growth factor receptors, cells can modulate the activity of intracellular signal transduction pathways. During Caenorhabditis elegans vulval development, a ternary complex consisting of the LIN-7, LIN-2 and LIN-10 PDZ domain proteins localizes the epidermal growth factor receptor (EGFR) to the basolateral compartment of the vulval precursor cells (VPCs) to allow efficient receptor activation by the inductive EGF signal from the anchor cell. We have identified EGFR substrate protein-8 (EPS-8) as a novel component of the EGFR localization complex that links receptor trafficking to cell fate specification. EPS-8 expression is upregulated in the primary VPCs, where it creates a positive feedback loop in the EGFR/RAS/MAPK pathway. The membrane-associated guanylate kinase LIN-2 recruits EPS-8 into the receptor localization complex to retain the EGFR on the basolateral plasma membrane, and thus allow maximal receptor activation in the primary cell lineage. Low levels of EPS-8 in the neighboring secondary VPCs result in the rapid degradation of the EGFR, allowing these cells to adopt the secondary cell fate. Extracellular signals thus regulate EGFR trafficking in a cell type-specific manner to control pattern formation during organogenesis. 相似文献
37.
Silvestri E de Lange P Moreno M Lombardi A Ragni M Feola A Schiavo L Goglia F Lanni A 《Biochimica et biophysica acta》2006,1757(5-6):486-495
Fibrates (anti-hyperlipidemic agents) enhance the mRNA expression of uncoupling protein 2 (UCP2) in the liver and that of uncoupling protein 3 (UCP3) in skeletal muscle in standard-diet-fed rats and induce a de novo expression of UCP3 (mRNA and protein) in the liver of high-fat-fed rats. Here, we report that in the liver of normal rats, fenofibrate induces a de novo expression of UCP3 and a 6-fold increase in UCP2 mRNA, whereas UCP2 protein was not detectable. Indeed, we evidenced an ORF in UCP2 exon 2 potentially able to inhibit the expression of the protein. Fenofibrate increases the expression and activity of hepatic enzymes and cofactors involved in lipid handling and UCP3 activity and, as is the case for UCP3, induces other muscle-specific genes (e.g., Carnitine palmitoyl transferase 1b and Ubiquinone biosynthesis protein COQ7 homolog). In addition, we demonstrated that in mitochondria from fenofibrate-treated rats a palmitoyl-carnitine-induced GDP-sensitive uncoupling takes place, involving UCP3 rather than other uncouplers (i.e., UCP2 and Adenine Nucleotide Translocase). Thus, the liver of fenofibrate-treated standard-diet- fed rat is a useful model for investigations of the biochemical functions of UCP3 and allowed us to demonstrate that fenofibrate programs a gene-expression pattern able to modulate lipid handling and UCP3 activation. 相似文献
38.
39.
Fabio Raimondo Andrea Nardini Sebastiano Salleo Santa Olga Cacciola Maria Assunta Lo Gullo 《Trees - Structure and Function》2010,24(2):327-333
Permanent xylem blockage is a common result of attacks by herbivores and fungi. The mitosporic fungus Phoma tracheiphila (Petri) Kantschaveli et Gikachvili, is the agent of a Citrus tracheomycosis (“malsecco disease”) causing xylem impairment and leading to leaf shedding and plant dieback. In the present
study, this pathogen was used for monitoring the effects of increasing levels of stem hydraulic resistance (R
stem) on leaf water status and gas exchange. In this view, measurements are reported of changes in the hydraulic resistance of
infected stems (R
stem) of C. aurantium (sour orange) during progressive and irreversible xylem blockage with parallel measurements of leaf water potential and conductance
to water vapour. Leaves were highly responsive to increasing R
stem as due to fungal infection, with substantial stomatal closure and drop in water potential. 相似文献
40.
Patrizia Trifil�� Fabio Raimondo Maria Assunta Lo Gullo Andrea Nardini Sebastiano Salleo 《Annals of botany》2010,106(2):333-341