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921.
Viviane Castelo Branco Reis André Moraes Nicola Osmar de Souza Oliveira Neto Vinícius Daniel Ferreira Batista Lidia Maria Pepe de Moraes Fernando Araripe Gon?alves Torres 《Journal of industrial microbiology & biotechnology》2012,39(11):1673-1683
Used for millennia to produce beverages and food, Saccharomyces cerevisiae also became a workhorse in the production of biofuels, most notably bioethanol. Yeast strains have acquired distinct characteristics that are the result of evolutionary adaptation to the stresses of industrial ethanol production. JP1 is a dominant industrial S. cerevisiae strain isolated from a sugarcane mill and is becoming increasingly popular for bioethanol production in Brazil. In this work, we carried out the genetic characterization of this strain and developed a set of tools to permit its genetic manipulation. Using flow cytometry, mating type, and sporulation analysis, we verified that JP1 is diploid and homothallic. Vectors with dominant selective markers for G418, hygromycin B, zeocin, and ρ-fluoro-dl-phenylalanine were used to successfully transform JP1 cells. Also, an auxotrophic ura3 mutant strain of JP1 was created by gene disruption using integration cassettes with dominant markers flanked by loxP sites. Marker excision was accomplished by the Cre/loxP system. The resulting auxotrophic strain was successfully transformed with an episomal vector that allowed green fluorescent protein expression. 相似文献
922.
Kym?M. Boycott Chandree?L. Beaulieu Kristin?D. Kernohan Ola?H. Gebril Aziz Mhanni Albert?E. Chudley David Redl Wen Qin Sarah Hampson Sébastien Küry Martine Tetreault Erik?G. Puffenberger James?N. Scott Stéphane Bezieau André Reis Steffen Uebe Johannes Schumacher Robert?A. Hegele D.?Ross McLeod Marina Gálvez-Peralta Jacek Majewski Vincent?T. Ramaekers CareRare Canada Consortium Daniel?W. Nebert A.?Micheil Innes Jillian?S. Parboosingh Rami Abou?Jamra 《American journal of human genetics》2015,97(6):886-893
Manganese (Mn) and zinc (Zn) are essential divalent cations used by cells as protein cofactors; various human studies and animal models have demonstrated the importance of Mn and Zn for development. Here we describe an autosomal-recessive disorder in six individuals from the Hutterite community and in an unrelated Egyptian sibpair; the disorder is characterized by intellectual disability, developmental delay, hypotonia, strabismus, cerebellar atrophy, and variable short stature. Exome sequencing in one affected Hutterite individual and the Egyptian family identified the same homozygous variant, c.112G>C (p.Gly38Arg), affecting a conserved residue of SLC39A8. The affected Hutterite and Egyptian individuals did not share an extended common haplotype, suggesting that the mutation arose independently. SLC39A8 is a member of the solute carrier gene family known to import Mn, Zn, and other divalent cations across the plasma membrane. Evaluation of these two metal ions in the affected individuals revealed variably low levels of Mn and Zn in blood and elevated levels in urine, indicating renal wasting. Our findings identify a human Mn and Zn transporter deficiency syndrome linked to SLC39A8, providing insight into the roles of Mn and Zn homeostasis in human health and development. 相似文献
923.
Erratum: GLUT4 translocation is not impaired after acute exercise in skeletal muscle of women with obesity and polycystic ovary syndrome 下载免费PDF全文
Wagner Silva Dantas José Antonio Miguel Marcondes Samuel Katsuyuki Shinjo Luiz Augusto Perandini Vanessa Olzon Zambelli Willian Das Neves Cristiano Roberto Grimaldi Barcellos Michele Patrocínio Rocha Viviane Dos Reis Vieira Yance Renato Tavares Dos Santos Pereira Igor Hisashi Murai Ana Lucia De Sá Pinto Hamilton Roschel Bruno Gualano 《Obesity (Silver Spring, Md.)》2016,24(9):2012-2012
924.
925.
Improved methodology for isolation of Acetobacter diazotrophicus and confirmation of its endophytic habitat 总被引:2,自引:0,他引:2
V. M. Reis F. L. Olivares J. Döbereiner 《World journal of microbiology & biotechnology》1994,10(4):401-405
Nitrogen-free, semi-solid defined medium with crystallized cane sugar (100 g/l) supplemented with cane juice (5 ml/l) was the most selective for isolating Acetobacter diazotrophicus. Surveys of A. diazotrophicus using this medium showed that >103 cells/g fresh wt were present at all sites in all parts of the sugar cane plant and in all trash samples examined, reaching up to 107/g. Additional samples, from forage grasses and cereals and from weed species collected within the sugar cane fields, were all negative. Heat treatment (50°C for 30 min) of the sugar cane setts did not affect A. diazotrophicus numbers within the plant. Nitrogenase activity of intact soil-plant systems in pots planted with heat-treated setts did not respond to inoculation with A. diazotrophicus. The endophytic habitat of this diazotroph and its propagation within the stem cuttings was confirmed.The authors are with EMBRAPA-CNPAB, Cx Postal 74.505, Seropédica, Rio de Janeiro, 23851-970, Brazil 相似文献
926.
Clonal variation in gene methylation: c-H-ras and alpha-hCG regions vary independently in human fibroblast lineages 总被引:1,自引:0,他引:1
The stability of DNA methylation has been followed in clonal lineages of human diploid fibroblasts, for the gene regions encoding the c-H-ras proto-oncogene and the alpha subunit of human chorionic gonadotropin (alpha-hCG). Although methylation losses predominated, both de novo gains and losses of cytosine methylation were observed in subclones and sub-subclones, at frequencies which differed between individual clonal lineages, and between the 2 gene regions compared. Methylation of these loci varied independently among clones; e.g., a lineage which showed frequent methylation loss in the c-H-ras gene region remained highly methylated for alpha-hCG, and vice versa. Thus, the fidelity with which DNA methylation is inherited in specific endogenous gene regions must be governed by a clone-specific property affecting local chromatin structure, but apparently not by gene expression per se. Late in the replicative life-span of diploid fibroblasts, as cell replication slowed, restriction patterns for methylation-sensitive enzymes became simpler and more discrete, while those for other enzymes did not change. This is interpreted as a consequence of 'clonal succession', in which the fastest-replicating or longest-lived clones/subclones eventually predominate in a cell population; it could also reflect a decreased rate or a non-random selection of methylation changes in late-passage cells. 相似文献
927.
Alan Teixeira Pasqualotto Sônia Maria de Lima Salgado Willian César Terra Bárbhara Joana dos Reis Fatobene Helbert Rezende de Oliveira Silveira Meline Oliveira Santos Vicente Paulo Campos Vânia Aparecida Silva 《Journal of Phytopathology》2020,168(4):220-227
Climate change greatly influences coffee production, especially in areas infested with plant-parasitic nematodes. In this study, coffee genotypes showed differences in their morphological and physiological characteristics when subjected to a water deficit and parasitism by Meloidogyne paranaensis. The cultivar IPR 100 had the largest superficial and volumetric root system area, even when parasitized. The two progenies (MG 0179-1 and MG 0179-3) and the cultivar Catuaí IAC 62 had a similar surface area (p < .05) when parasitized. However, the root surface area and volume of MG 0179-3 increased by 96% and 400%, respectively, when parasitized by M. paranaensis. On the other hand, Catuaí IAC 62 had a 31% reduction in root surface area. Catuai 62 and IPR 100 showed higher sensitivity to drought when parasitized because of the increased photochemical sensitivity and reduction in photochemical quenching. In MG 0179-1 and MG 0179-3, an increase in non-photochemical quenching occurred in response to stress, indicating that these progenies use a photochemical response to protect photosystem II. In this work, MG 0179-3, which is resistant to M. paranaensis, was remarkable because, interestingly, the infestation caused an increase in its root surface area. In addition, MG 0179-3 had relatively good photochemical performance under water deficit and M. paranaensis parasitism. 相似文献
928.
P J Reis D A Tunks R D Rigby T C Morton S G Munro 《Australian journal of biological sciences》1983,36(2):157-170
Sheep were given intravenous infusions of ethionine together with cycloleucine or reduced glutathione, in attempts to prevent the inhibition of wool growth by ethionine. Other sheep were given cycloleucine alone to measure effects on wool growth. Twenty-two compounds related to cystine, methionine, ethionine, lysine, phenylalanine and tyrosine were given as intravenous infusions to sheep to investigate their potential as depilatory agents. Nineteen of these compounds were also tested in mice during their first cycle of hair growth. The concurrent administration of cycloleucine with ethionine prevented the weakening of wool fibres caused by ethionine, but reduced glutathione was ineffective. Cycloleucine weakened wool fibres, as judged subjectively, and caused a small reduction in fibre diameter. Selenocystine and selenomethionine caused some hair loss in mice but selenocystine was also toxic. Both seleno-amino acids were toxic for sheep; selenocystine was lethal at 0.025 mmol kg-0.75 and selenomethionine at 0.09 mmol kg-0.75. Doses that permitted survival of sheep did not have depilatory effects. However, the presence of autophagic vacuoles in the cytoplasm of follicle bulb cells of sheep indicated that a toxic dose of selenocystine had potential depilatory activity. Other compounds investigated did not induce loss of wool or hair. Some compounds, notably 3-methylthiopropionic acid and S-(2-aminoethyl)-L-cysteine, were toxic to mice but not sheep. The methionine analogue, methoxinine (O-methyl-DL-homoserine), caused a substantial reduction in the strength of wool fibres and a prolonged alteration of the crimp pattern. It is suggested tentatively that cycloleucine inhibits methionine adenosyltransferase and thereby reduces or prevents the formation of S-adenosylethionine. The failure of various compounds related to methionine and ethionine to have any depilatory activity in sheep supports the view that ethionine influences wool growth via the formation of S-adenosylethionine. 相似文献
929.
da Silva Nayara Tayane Silva Lázara Aline Simões Reis Aryane Campos Machado Mariana de Matos Elyabe Monteiro Viccini Lyderson Facio Otoni Wagner Campos de Carvalho Ilio Fealho Rocha Diego Ismael da Silva Maurecilne Lemes 《Plant Cell, Tissue and Organ Culture》2020,142(3):613-624
Plant Cell, Tissue and Organ Culture (PCTOC) - Triploid plants represent an important resource for the breeding of fruit and ornamental plants. Here, we report a facile and robust system for... 相似文献
930.
Steffen Uebe Francesca Pasutto Mandy Krumbiegel Denny Schanze Arif B Ekici André Reis 《BMC bioinformatics》2010,11(1):472