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531.
Background
The complexity of mitochondrial complex I (CI; NADH:ubiquinone oxidoreductase) has increased considerably relative to the homologous complex in bacteria. Comparative analyses of CI composition in animals, fungi and land plants/green algae suggest that novel components of mitochondrial CI include a set of 18 proteins common to all eukaryotes and a variable number of lineage-specific subunits. In plants and green algae, several purportedly plant-specific proteins homologous to γ-type carbonic anhydrases (γCA) have been identified as components of CI. However, relatively little is known about CI composition in the unicellular protists, the characterizations of which are essential to our understanding of CI evolution. 相似文献532.
De Angelis M Rizzello CG Fasano A Clemente MG De Simone C Silano M De Vincenzi M Losito I Gobbetti M 《Biochimica et biophysica acta》2006,1762(1):80-93
The native structure and distribution of gliadin epitopes responsible for Celiac Sprue (CS) may be influenced by cereal food processing. This work was aimed at showing the capacity of probiotic VSL#3 to decrease the toxicity of wheat flour during long-time fermentation. VSL#3 (10(9) cfu/ml) hydrolyzed completely the alpha2-gliadin-derived epitopes 62-75 and 33-mer (750 ppm). Two-dimensional electrophoresis, immunological (R5 antibody) and mass spectrometry analyses showed an almost complete degradation of gliadins during long-time fermentation of wheat flour by VSL#3. Gliadins non-hydrolyzed during fermentation by VSL#3 were subjected to peptic-tryptic (PT) digestion and analyzed by CapLC-ESI-Q-ToF-MS (Capillary Liquid Chromatography-Electrospray Ionization-Quadrupole-Time of Flight-Mass Spectrometry). Search for several epitopes showed the only presence of alpha2-gliadin-fragment 62-75 at a very low concentration (sub-ppm range). Compared to IEC-6 cells exposed to intact gliadins extracted from the chemically acidified dough (control), VSL#3 pre-digested gliadins caused a less pronounced reorganization of the intracellular F-actin which was mirrored by an attenuated effect on intestinal mucosa permeability. The release of zonulin from intestinal epithelial cells treated with gliadins was considerably lower when digested with VSL#3. Agglutination test on K 562 (S) cells showed that the PT-digest of wheat flour treated with VSL#3 increased the Minimal Agglutinating Activity of ca. 100 times. Wheat proteins were extracted from doughs and subjected to PT digestion. Compared to PT-digest from chemically acidified dough, celiac jejunal biopsies exposed to the PT-digest from the dough fermented by VSL#3 did not show an increase of the infiltration of CD3(+) intraepithelial lymphocytes. Proteolytic activity by probiotic VSL#3 may have an importance during food processing to produce pre-digested and tolerated gliadins for increasing the palatability of gluten-free products. 相似文献
533.
Clemente Capasso Vincenzo Carginale Marilisa Riggio Rosaria Scudiero Piero Andrea Temussi Francesca Trinchella Elio Parisi 《Reviews in Environmental Science and Biotechnology》2006,5(2-3):253-267
Organisms from yeast to mammals contain cysteine-rich, heavy metal binding proteins termed metallothioneins. The putative roles of these proteins are trace metal homeostasis and detoxification of poisonous heavy metals. The highly conserved chemical composition and the structural constraints led to the conclusion that metallothioneins of different origin must display remarkably similar features. The present review aims at surveying the studies carried out on the metallothioneins of Antarctic Notothenioidei, a dominating fish group endowed of a number of striking adaptive characters, including reduced (or absent) hematocrit and presence of antifreeze glycoproteins. Given the unique peculiarities of the Antarctic environment, a comparative study of the features of notothenioid metallothioneins could provide new insights into the role of these proteins in physiology and toxicology. The results summarized here show that the metallothioneins of this fish group display a number of features at the level of evolution, expression pattern, structure and function remarkably different from those of mammal metallothioneins. 相似文献
534.
Stabilization of the metaphase spindle by Cdc14 is required for recombinational DNA repair 下载免费PDF全文
Encarnación Dueñas Peter Faull Pedro Rodríguez Cutillas Andrés Clemente‐Blanco 《The EMBO journal》2017,36(1):79-101
Cells are constantly threatened by multiple sources of genotoxic stress that cause DNA damage. To maintain genome integrity, cells have developed a coordinated signalling network called DNA damage response (DDR). While multiple kinases have been thoroughly studied during DDR activation, the role of protein dephosphorylation in the damage response remains elusive. Here, we show that the phosphatase Cdc14 is essential to fulfil recombinational DNA repair in budding yeast. After DNA double‐strand break (DSB) generation, Cdc14 is transiently released from the nucleolus and activated. In this state, Cdc14 targets the spindle pole body (SPB) component Spc110 to counterbalance its phosphorylation by cyclin‐dependent kinase (Cdk). Alterations in the Cdk/Cdc14‐dependent phosphorylation status of Spc110, or its inactivation during the induction of a DNA lesion, generate abnormal oscillatory SPB movements that disrupt DSB‐SPB interactions. Remarkably, these defects impair DNA repair by homologous recombination indicating that SPB integrity is essential during the repair process. Together, these results show that Cdc14 promotes spindle stability and DSB‐SPB tethering during DNA repair, and imply that metaphase spindle maintenance is a critical feature of the repair process. 相似文献
535.
Jagdeep Kaur John Fellers Alok Adholeya Siva L. S. Velivelli Kaoutar El-Mounadi Natalya Nersesian Thomas Clemente Dilip Shah 《Transgenic research》2017,26(1):37-49
Rust fungi of the order Pucciniales are destructive pathogens of wheat worldwide. Leaf rust caused by the obligate, biotrophic basidiomycete fungus Puccinia triticina (Pt) is an economically important disease capable of causing up to 50 % yield losses. Historically, resistant wheat cultivars have been used to control leaf rust, but genetic resistance is ephemeral and breaks down with the emergence of new virulent Pt races. There is a need to develop alternative measures for control of leaf rust in wheat. Development of transgenic wheat expressing an antifungal defensin offers a promising approach to complement the endogenous resistance genes within the wheat germplasm for durable resistance to Pt. To that end, two different wheat genotypes, Bobwhite and Xin Chun 9 were transformed with a chimeric gene encoding an apoplast-targeted antifungal plant defensin MtDEF4.2 from Medicago truncatula. Transgenic lines from four independent events were further characterized. Homozygous transgenic wheat lines expressing MtDEF4.2 displayed resistance to Pt race MCPSS relative to the non-transgenic controls in growth chamber bioassays. Histopathological analysis suggested the presence of both pre- and posthaustorial resistance to leaf rust in these transgenic lines. MtDEF4.2 did not, however, affect the root colonization of a beneficial arbuscular mycorrhizal fungus Rhizophagus irregularis. This study demonstrates that the expression of apoplast-targeted plant defensin MtDEF4.2 can provide substantial resistance to an economically important leaf rust disease in transgenic wheat without negatively impacting its symbiotic relationship with the beneficial mycorrhizal fungus. 相似文献
536.
Francisco Salatiel Clemente de Souza Armando Muniz Calouro 《Primates; journal of primatology》2018,59(5):469-474
The predation of army ants (Eciton rapax) was recorded during an observational study of the feeding behavior of a group of titi monkeys (Plecturocebus toppini) in an urban fragment of forest in Acre, Brazil. During one observed event, the group’s adult female used its tail to retrieve ants, a type of behavior not observed previously in this genus. All incidents of on-forest floor foraging occurred during the dry season, when fruit was least abundant in the forest, while on other occasions, the ants were captured from tree branches and leaves. The observation of predation and ground-level foraging recorded in this study reinforce the adaptive capacity of P. toppini for survival in fragmented forests, and this was also the first record of the predation of army ants by this titi species. 相似文献
537.
Alfonso González Ramírez Juan José Calvo Aguirre Pilar Lekuona Ancizar Juan Luis González Oliveras Teresa Marcellán Benavente Ana Ruiz de Gordoa Armendia Antoni Salvá Casanovas Pablo Alcalde Tirado Teresa González Alonso Reyes Padilla Clemente Mercedes Clerencia Sierra Elena Ubis Diez 《Revista espa?ola de geriatría y gerontología》2013
The Workshop on Osteoporosis, Falls and Fractures (GCOF) of The Spanish Geriatrics and Gerontology Society (SEGG) formed a committee in order to review the state of the art on the detection, risk factors and assessment tools for falls, and intervention protocols when falls occurs in nursing homes, long-term hospitals or medium-stay units. The different patient profiles are described in order to make a comprehensive approach to this heterogeneous topic and population, offering a risk classification and specific advice according to these categories. 相似文献
538.
539.
Effect of cadmium and calcium treatments on phytochelatin and glutathione levels in citrus plants 总被引:1,自引:0,他引:1
M. F. López‐Climent V. Arbona R. M. Pérez‐Clemente S. I. Zandalinas A. Gómez‐Cadenas 《Plant biology (Stuttgart, Germany)》2014,16(1):79-87
Industry residues, phosphate fertilisers and wastewater as a source of irrigation have considerably increased levels of heavy metals in the soil, mainly cadmium (Cd2+). To test the effects of a calcium (Ca2+) treatment on Cd2+ accumulation and plant tolerance to this heavy metal, plants of two citrus genotypes, Cleopatra mandarin (CM) and Carrizo citrange (CC), were watered with increasing concentrations of Cd2+, and phytochelatin (PC) and glutathione (GSH) content were measured. Both genotypes were able to synthesise PCs in response to heavy metal intoxication, although CM seems to be a better Cd2+ excluder than CC. However, data indicate that CC plants had a higher capacity for regenerating GSH than CM plants. In this context, the effects of Ca2+ treatment on Cd2+ accumulation, plant survival and PC, GSH and oxidised glutathione (GSSG) content were assessed. Data indicate that treatment with Ca2+ had two positive effects on citrus physiology: it reduced Cd+2 uptake into roots and also increased GSH content (even in the absence of Cd2+). Overall, the data indicate that although Cd2+ exclusion is a powerful mechanism to avoid heavy metal build‐up into photosynthetic organs, the capacity to maintain optimum GSH levels to feed PC biosynthesis could also be an important factor in stress tolerance. 相似文献
540.
Expression of Chlorovirus MT325 aquaglyceroporin (aqpv1) in tobacco and its role in mitigating drought stress 总被引:1,自引:0,他引:1
Saadia Bihmidine Mingxia Cao Ming Kang Tala Awada James L. Van Etten David D. Dunigan Tom E. Clemente 《Planta》2014,240(1):209-221