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751.
Phosphomannomutase (PMM) is a key enzyme, which catalyses one of the first steps in the glycosylation pathway, the conversion of D-mannose-6-phosphate to D-mannose-1-phosphate. The latter is the substrate for the synthesis of GDP-mannose, which serves as the mannosyl donor for the glycosylation reactions in eukaryotic cells. In the yeast Saccharomyces cerevisiae PMM is encoded by the gene SEC53 (ScSEC53) and the deficiency of PMM activity leads to severe defects in both protein glycosylation and secretion. We report here on the isolation of the Kluyveromyces lactis SEC53 (KlSEC53) gene from a genomic library by virtue of its ability to complement a Saccharomyces cerevisiae sec53 mutation. The sequenced DNA fragment contained an open reading frame of 765 bp, coding for a predicted polypeptide, KlSec53p, of 254 amino acids. The KlSec53p displays a high degree of homology with phosphomannomutases from other yeast species, protozoans, plants and humans. Our results have demonstrated that KlSEC53 is the functional homologue of the ScSEC53 gene. Like ScSEC53, the KlSEC53 gene is essential for K. lactis cell viability. Phenotypic analysis of a K. lactis strain overexpressing the KlSEC53 gene revealed defects expected for impaired cell wall integrity. 相似文献
752.
Marianna Mastromatteo Amalia Conte Michele Faccia Matteo Alessandro Del Nobile Angelo Vittorio Zambrini 《Journal of dairy science》2014
In this work, the effect of active coating on the shelf life of low-moisture Mozzarella cheese packaged in air and modified atmosphere (MAP) was studied. The active coating was based on sodium alginate (2%, wt/vol) and potassium sorbate (1%, wt/vol). The MAP was made up of 75% CO2 and 25% N2 (MAP1), 25% CO2 and 75% N2 (MAP2), or 50% CO2 and 50% N2 (MAP3). The product quality decay was assessed by monitoring microbiological and sensory changes during storage at 4, 8, and 14°C. Results showed that the combination of active coating and MAP was able to improve the preservation of low-moisture Mozzarella cheese. Specifically, the shelf life increased up to 160 d for samples stored at 4°C, and 40 and 11 d for those at 8 and 14°C, respectively. A faster quality decay for untreated samples packaged in air was observed. In particular, the Pseudomonas spp. growth and the appearance of molds were responsible for product unacceptability. The combination of active coating and MAP represents a strategic solution to prolong the shelf life of low-moisture Mozzarella cheese and to ensure the safety of the product under thermal abuse conditions. 相似文献
753.
Jéssica Rosso Motta Ivo Emilio da Cruz Jung Verônica Farina Azzolin Cibele Ferreira Teixeira Luiza Elizabete Braun Daniel Augusto De Oliveira Nerys Marco Aurélio Echart Motano Marta Maria Medeiros Frescura Duarte Ednea Aguiar Maia-Ribeiro Ivana Beatrice Mânica da Cruz Fernanda Barbisan 《Journal of Food Biochemistry》2021,45(2):e13596
754.
Capozzi V Ladero V Beneduce L Fernández M Alvarez MA Benoit B Laurent B Grieco F Spano G 《Food microbiology》2011,28(3):434-439
Enterococcus faecium strains were isolated from red wines undergoing malolactic fermentation and identified by comparison of their 16S rDNA gene sequences with those included in the GenEMBL Databases. The tyrosine decarboxylase gene was identified in all the strains analysed by PCR using gene-specific primers and the ability to produce tyramine in a synthetic media was analysed by RP-HPLC. Survival of an E. faecium strain was also evaluated in microvinification assays using two different musts with different ethanol concentrations (10% and 12% (v/v)). Tyramine production was monitored during the vinification trials. Our results suggest that E. faecium strains isolated from wine are able to produce tyramine and tolerate wine conditions following a pre-acidic stress. 相似文献
755.
Margaret Ottaviano Emilio Francesco Giunta Pasquale Rescigno Ricardo Pereira Mestre Laura Marandino Marianna Tortora Vittorio Riccio Sara Parola Milena Casula Panagiotis Paliogiannis Antonio Cossu Ursula Maria Vogl Davide Bosso Mario Rosanova Brunello Mazzola Bruno Daniele Giuseppe Palmieri Giovannella Palmieri 《International journal of molecular sciences》2021,22(13)
The cure rate of germ cell tumours (GCTs) has significantly increased from the late 1970s since the introduction of cisplatin-based therapy, which to date remains the milestone for GCTs treatment. The exquisite cisplatin sensitivity has been mainly explained by the over-expression in GCTs of wild-type TP53 protein and the lack of TP53 somatic mutations; however, several other mechanisms seem to be involved, many of which remain still elusive. The findings about the role of TP53 in platinum-sensitivity and resistance, as well as the reported evidence of second cancers (SCs) in GCT patients treated only with surgery, suggesting a spectrum of cancer predisposing syndromes, highlight the need for a deepened understanding of the role of TP53 in GCTs. In the following report we explore the complex role of TP53 in GCTs cisplatin-sensitivity and resistance mechanisms, passing through several recent genomic studies, as well as its role in GCT patients with SCs, going through our experience of Center of reference for both GCTs and cancer predisposing syndromes. 相似文献
756.
Flávio Beneduce Alexandre Bellegard Farina 《Journal of Phase Equilibria and Diffusion》2017,38(3):252-256
The knowledge of the thermodynamic features of the NiO-CaO system is of fundamental importance to the modelling of metal-slag-refractory equilibrium of Ni-based alloys melting process in electric arc furnaces as well as for development a self-consistent multi-component thermodynamic database for nickel extraction from laterite ores. The existing assessment for liquid slag, based on the quasichemical model modified by Pelton and Blander cannot be in the SLAG database used by Thermo-Calc software which is based on a different thermodynamic model to slag phase. The present work presents the modelling of CaO-NiO using the quasichemical cell model of Kapoor-Frohberg-Gaye for the liquid slag phase. The data utilized for this modelling were activities, liquidus and solvus compositions as well as magnetic parameters of the phase NiO. The optimization was performed with the PARROT® module of Thermo-Calc® software. The results obtained, the phase diagram and the activities diagrams, are in good agreement with the literature data. 相似文献
757.
Lucia Cappabianca Michela Sebastiano Marianna Ruggieri Maddalena Sbaffone Veronica Zelli Antonietta Rosella Farina Andrew Reay Mackay 《International journal of molecular sciences》2022,23(18)
Patients with advanced neuroblastoma (NB) receive multimodal clinical therapy, including the potent anthracycline chemotherapy drug doxorubicin (Dox). The acquisition of Dox resistance, however, is a major barrier to a sustained response and leads to a poor prognosis in advanced disease states, reinforcing the need to identify and inhibit Dox resistance mechanisms. In this context, we report on the identification and inhibition of a novel Dox resistance mechanism. This mechanism is characterized by the Dox-induced activation of the oncogenic TrkAIII alternative splice variant, resulting in increased Dox resistance, and is blocked by lestaurtinib, entrectinib, and crizotinib tyrosine kinase and LY294002 IP3-K inhibitors. Using time lapse live cell imaging, conventional and co-immunoprecipitation Western blots, RT-PCR, and inhibitor studies, we report that the Dox-induced TrkAIII activation correlates with proliferation inhibition and is CDK1- and Ca2+-uniporter-independent. It is mediated by ryanodine receptors; involves Ca2+-dependent interactions between TrkAIII, calmodulin and Hsp90; requires oxygen and oxidation; occurs within assembled ERGICs; and does not occur with fully spliced TrkA. The inhibitory effects of lestaurtinib, entrectinib, crizotinib, and LY294002 on the Dox-induced TrkAIII and Akt phosphorylation and resistance confirm roles for TrkAIII and IP3-K consistent with Dox-induced, TrkAIII-mediated pro-survival IP3K/Akt signaling. This mechanism has the potential to select resistant dormant TrkAIII-expressing NB cells, supporting the use of Trk inhibitors during Dox therapy in TrkAIII-expressing NBs. 相似文献
758.
Laura Ielo Vincenzo Patamia Andrea Citarella Thomas Efferth Nasim Shahhamzehei Tanja Schirmeister Claudio Stagno Thierry Langer Antonio Rescifina Nicola Micale Vittorio Pace 《International journal of molecular sciences》2022,23(20)
The ubiquitin-proteasome pathway (UPP) is the major proteolytic system in the cytosol and nucleus of all eukaryotic cells. The role of proteasome inhibitors (PIs) as critical agents for regulating cancer cell death has been established. Aziridine derivatives are well-known alkylating agents employed against cancer. However, to the best of our knowledge, aziridine derivatives showing inhibitory activity towards proteasome have never been described before. Herein we report a new class of selective and nonPIs bearing an aziridine ring as a core structure. In vitro cell-based assays (two leukemia cell lines) also displayed anti-proliferative activity for some compounds. In silico studies indicated non-covalent binding mode and drug-likeness for these derivatives. Taken together, these results are promising for developing more potent PIs. 相似文献
759.
Vittorio Vellani Giovanna Mauro Gian Carlo Demontis 《International journal of molecular sciences》2022,23(21)
Unidentified pathogenetic mechanisms and genetic and clinical heterogeneity represent critical factors hindering the development of treatments for inherited retinal dystrophies. Frameshift mutations in Cacna2d4, which codes for an accessory subunit of voltage-gated calcium channels (VGCC), cause cone-rod dystrophy RCD4 in patients, but the underlying mechanisms remain unknown. To define its pathogenetic mechanisms, we investigated the impact of a Cacna2d4 frameshift mutation on the electrophysiological profile and calcium handling of mouse rod photoreceptors by patch-clamp recordings and calcium imaging, respectively. In mutant (MUT) rods, the dysregulation of calcium handling extends beyond the reduction in calcium entry through VGCC and surprisingly involves internal calcium stores’ depletion and upregulation of calcium entry via non-selective cationic channels (CSC). The similar dependence of CSC on basal calcium levels in WT and MUT rods suggests that the primary defect in MUT rods lies in defective calcium stores. Calcium stores’ depletion, leading to upregulated calcium and sodium influx via CSC, represents a novel and, so far, unsuspected consequence of the Cacna2d4 mutation. Blocking CSC may provide a novel strategy to counteract the well-known pathogenetic mechanisms involved in rod demise, such as the reticulum stress response and calcium and sodium overload due to store depletion. 相似文献
760.
Camillo Porcaro Antonio Di Renzo Emanuele Tinelli Vincenzo Parisi Cherubino Di Lorenzo Francesca Caramia Marco Fiorelli Giada Giuliani Ettore Cioffi Stefano Seri Vittorio Di Piero Francesco Pierelli Giorgio Di Lorenzo Gianluca Coppola 《International journal of molecular sciences》2022,23(21)
The role of the hypothalamus and the limbic system at the onset of a migraine attack has recently received significant interest. We analyzed diffusion tensor imaging (DTI) parameters of the entire hypothalamus and its subregions in 15 patients during a spontaneous migraine attack and in 20 control subjects. We also estimated the non-linear measure resting-state functional MRI BOLD signal’s complexity using Higuchi fractal dimension (FD) and correlated DTI/fMRI findings with patients’ clinical characteristics. In comparison with healthy controls, patients had significantly altered diffusivity metrics within the hypothalamus, mainly in posterior ROIs, and higher FD values in the salience network (SN). We observed a positive correlation of the hypothalamic axial diffusivity with migraine severity and FD of SN. DTI metrics of bilateral anterior hypothalamus positively correlated with the mean attack duration. Our results show plastic structural changes in the hypothalamus related to the attacks severity and the functional connectivity of the SN involved in the multidimensional neurocognitive processing of pain. Plastic changes to the hypothalamus may play a role in modulating the duration of the attack. 相似文献