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101.
R. A. B. Pessoni R. C. L. Figueiredo-Ribeiro M. R. Braga 《Journal of applied microbiology》1999,87(1):141-147
Extracellular inulinases from Penicillium janczewskii were obtained from the filtrate of 12 day-old cultures supplemented with inulin from Vernonia herbacea. Crude filtrates and partially-purified enzyme preparations (peaks I and II) were active on inulin, sucrose and raffinose. The apparent M(r) of the enzymes from peaks I and II were 48 and 66 kDa, respectively. The apparent K(m) (mmol l-1) values of peak I were 0.43 for inulin and 18.7 for sucrose; for peak II they were 0.87 and 18.5 for inulin and sucrose, respectively. Their temperature and pH optima were 55 degrees C and 5.0, respectively. Both peaks catalysed the hydrolysis of beta-(2,1) fructans more rapidly than beta-(2,6) fructans. Free fructose was the predominant product released from inulin, indicating that these enzymes display exo-inulinase activity. In view of these characteristics, the yield and the high specific activity towards beta-(2,1) fructans, inulinases from P. janczewskii can be utilized for the preparation of fructose syrup from inulin. 相似文献
102.
Summary A family of an isolated patient with Becker muscular dystrophy has been investigated by DNA analysis. Southern blotting and
hybridization were performed with six probes (C7, pERT87.15, pERT87.1, pXJ1.1, pXJ2.3, 754) mapping in the Xp21 region. A
deletion within the pXJ region was demonstrated in the proband, his mother and all three sisters. The segregation pattern
for the restriction fragment length polymorphisms (RFLPs) observed with the pXJ probes as well as with pERT87.15, pERT87.1
and 754 probes indicates that the deletion is of grandpaternal origin. 相似文献
103.
Elizabeth Nichols María Uriarte Carlos A. Peres Julio Louzada Rodrigo Fagundes Braga Gustavo Schiffler Whaldener Endo Sacha H. Spector 《PloS one》2013,8(10)
Human presence and activity in tropical forest is thought to exert top-down regulation over the various ‘green-world’ pathways of plant-based foodwebs. However, these effects have never been explored for the ‘brown-world’ pathways of fecal-detritus webs. The strong effects of humans on tropical game mammals are likely to indirectly influence fecal detritivores (including Scarabaeine dung beetles), with subsequent indirect impacts on detrivore-mediated and plant-facilitating detrital processes. Across a 380-km gradient of human influence in the western Brazilian Amazon, we conducted the first landscape-level assessment of human-induced cascade effects on the fecal detritus pathway, by coupling data on human impact, game mammal and detritivore community structure, and rate measurements of a key detritus process (i.e. dung beetle-mediated secondary seed dispersal). We found evidence that human impact indirectly influences both the diversity and biomass of fecal detritivores, but not detritivore-mediated processes. Cascade strength varied across detritivore groups defined by species'' traits. We found smaller-bodied dung beetles were at higher risk of local decline in areas of human presence, and that body size was a better predictor of cascade structure than fecal resource manipulation strategy. Cascade strength was also stronger in upland, unflooded forests, than in seasonally flooded forests. Our results suggest that the impact of human activity in tropical forest on fecal-detritus food web structure is mediated by both species'' traits and habitat type. Further research will be required to determine the conditions under which these cascade effects influence fecal-detritus web function. 相似文献
104.
105.
A. Braga P. Ferreira J. Oliveira I. Rocha N. Faria 《World journal of microbiology & biotechnology》2018,34(8):122
The polyphenol resveratrol (3,5,4′-trihydroxystilbene) is a well-known plant secondary metabolite, commonly used as a medical ingredient and a nutritional supplement. Due to its health-promoting properties, the demand for resveratrol is expected to continue growing. This stilbene can be found in different plants, including grapes, berries (blackberries, blueberries and raspberries), peanuts and their derived food products, such as wine and juice. The commercially available resveratrol is usually extracted from plants, however this procedure has several drawbacks such as low concentration of the product of interest, seasonal variation, risk of plant diseases and product stability. Alternative production processes are being developed to enable the biotechnological production of resveratrol by genetically engineering several microbial hosts, such as Escherichia coli, Corynebacterium glutamicum, Lactococcus lactis, among others. However, these bacterial species are not able to naturally synthetize resveratrol and therefore genetic modifications have been performed. The application of emerging metabolic engineering offers new possibilities for strain and process optimization. This mini-review will discuss the recent progress on resveratrol biosynthesis in engineered bacteria, with a special focus on the metabolic engineering modifications, as well as the optimization of the production process. These strategies offer new tools to overcome the limitations and challenges for microbial production of resveratrol in industry. 相似文献
106.
Milene A. Andrade Maria das Graças Cardoso Paulo S. C. Preté Maurílio J. Soares Camila M. O. de Azeredo Marcus V. C. Trento Mariana A. Braga Silvana Marcussi 《化学与生物多样性》2018,15(5)
The objective of this study was to determine cytotoxic activity, hemolytic activity, and to evaluate the ability of the essential oil from Cinnamodendron dinisii to induce DNA fragmentation of human lymphocytes. The essential oil was obtained by hydrodistillation. Cytotoxic activity was determined by the MTT method. Hemolytic activity was evaluated by spectrophotometric quantification of hemoglobin released by erythrocytes. Damage to lymphocyte DNA molecules was assessed by the Comet assay. The essential oil under study showed high cytotoxic activity on Vero cells (CC50 = 35.72 μg/mL) and induced hemolysis in both hematocrits, besides leading to the oxidation of hemoglobin released. The genotoxic activity of C. dinisii essential oil was also observed, which induced concentration‐dependent DNA fragmentation of human lymphocytes and, at 50 μL/mL, it was more active than the positive control. The essential oil from C. dinisii has a toxic action, suggesting a special attention in the application of this oil to health‐promoting activities; however, among its components, there are molecules with potential for future application in anticancer therapies. 相似文献
107.
Marcos Vinicius Antunes de Lemos Elisa Peripolli Mariana Piatto Berton Fabiele Loise Braga Feitosa Bianca Ferreira Olivieri Nedenia Bonvino Stafuzza Rafael Lara Tonussi Sabrina Kluska Hermenegildo Lucas Justino Chiaia Lenise Mueller Adrielli Mathias Ferrinho Angelica Simone Cravo Prereira Henrique Nunes de Oliveira Lucia Galvão de Albuquerque Fernando Baldi 《Journal of applied genetics》2018,59(2):203-223
The aim of this study was to analyze the association between the copy number variation regions (CNVRs) and fatty acid profile phenotypes for saturated (SFA), monosaturated (MUFA), polyunsaturated (PUFA), ω6 and ω3 fatty acids, PUFA/SFA and ω6/ω3 ratios, as well as for their sums, in Nellore cattle (Bos primigenius indicus). A total of 963 males were finished in feedlot and slaughtered with approximately 2 years of age. Animals were genotyped with the BovineHD BeadChip (Illumina Inc., San Diego, CA, USA). The copy number variation (CNV) detection was performed using the PennCNV algorithm. Log R ratio (LRR) and allele B frequency (BAF) were used to estimate the CNVs. The association analyses were done using the CNVRuler software and applying a logistic regression model. The phenotype was adjusted using a linear model considering the fixed effects of contemporary group and the animal age at slaughter. The fatty acid profile was analyzed on samples of longissimus thoracis muscle using gas chromatography with a 100-m capillary column. For the association analysis, the adjusted phenotypic values were considered for the traits, while the data was adjusted for the effects of the farm and year of birth, management groups at birth, weaning, and superannuation. A total of 186 CNVRs were significant for SFA (43), MUFA (42), PUFA (66), and omega fatty acid (35) groups, totaling 278 known genes. On the basis of the results, several genes were associated with several fatty acids of different saturations. Olfactory receptor genes were associated with C12:0, C14:0, and C18:0 fatty acids. The SAMD8 and BSCL2 genes, both related to lipid metabolic process, were associated with C12:0. The RAPGEF6 gene was found to be associated with C18:2 cis-9 cis-12 n-6, and its function is related to regulation of GTPase activity. Among the results, we highlighted the olfactory receptor activity (GO:0004984), G-protein-coupled receptor activity (GO:0004930), potassium:proton antiporter activity (GO:0015386), sodium:proton antiporter activity (GO:0015385), and odorant-binding (GO:0005549) molecular functions. A large number of genes associated with fatty acid profile within the CNVRs were identified in this study. These findings must contribute to better elucidate the genetic mechanism underlying the fatty acid profile of intramuscular fat in Nellore cattle. 相似文献
108.
Thayana Conceição Barbosa Bruno Almeida Lopes Caroline Barbieri Blunck Marcela Braga Mansur Adriana Vanessa Santini Deyl Mariana Emerenciano Maria S. Pombo-de-Oliveira 《BMC medical genomics》2018,11(1):122
Background
Chromosome translocations are a hallmark of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Additional genomic aberrations are also crucial in both BCP-ALL leukemogenesis and treatment management. Herein, we report the phenotypic and molecular cytogenetic characterization of an extremely rare case of BCP-ALL harboring two concomitant leukemia-associated chromosome translocations: t(1;19)(q23;q13.3) and t(9;17)(p13;q11.2). Of note, we described a new rearrangement between exon 6 of PAX5 and a 17q11.2 region, where intron 3 of SPECC1 is located. This rearrangement seems to disrupt PAX5 similarly to a PAX5 deletion. Furthermore, a distinct karyotype between diagnosis and relapse samples was observed, disclosing a complex clonal evolution during leukemia progression.Case presentation
A 16-year-old boy was admitted febrile with abdominal and joint pain. At clinical investigation, he presented with anemia, splenomegaly, low white blood cell count and 92% lymphoblast. He was diagnosed with pre-B ALL and treated according to high risk GBTLI-ALL2009. Twelve months after complete remission, he developed a relapse in consequence of a high central nervous system and bone marrow infiltration, and unfortunately died.Conclusions
To our knowledge, this is the first report of a rearrangement between PAX5 and SPECC1. The presence of TCF3-PBX1 and PAX5-rearrangement at diagnosis and relapse indicates that both might have participated in the malignant transformation disease maintenance and dismal outcome.109.
José Cavalcante Souza Vieira Camila Pereira Braga Grasieli de Oliveira Cilene do Carmo Federici Padilha Paula Martin de Moraes Luiz Fabricio Zara Aline de Lima Leite Marília Afonso Rabelo Buzalaf Pedro de Magalhães Padilha 《Biological trace element research》2018,181(1):164-172
Poly-trans-[(2-carboxyethyl)germasesquioxane] (Ge-132) is a water-soluble organogermanium compound that exerts various physiological effects, including anti-inflammatory activity and pain relief. In water, Ge-132 is hydrolyzed to 3-(trihydroxygermyl)propanoic acid (THGP), which in turn is capable of interacting with cis-diol compounds through its trihydroxy group, indicating that this compound could also interact with diol-containing nucleic acid constituents. In this study, we evaluated the ability of THGP to interact with nucleosides or nucleotides via nuclear magnetic resonance (NMR) analysis. In addition, we evaluated the effect of added THGP on the enzymatic activity of adenosine deaminase (ADA) when using adenosine or 2′-deoxyadenosine as a substrate. In solution, THGP indeed formed complexes with nucleotides or nucleosides through their cis-diol group. Moreover, the ability of THGP to form complexes with nucleotides was influenced by the number of phosphate groups present on the ribose moiety. Notably, THGP also inhibited the catalysis of adenosine by ADA in a concentration-dependent manner. Thus, interactions between THGP and important biological nucleic acid constituents might be implicated in the physiological effects of Ge-132. 相似文献
110.
Two Lower Liassic sections of the Banos de Alhama de Granada outcrop are studied. The Hettangian and Sinemurian ammonite assemblages are detailed and a reinterpretation of the stratigraphy of the outcrop made.The ammonites collected show a clear mediterranean character. A biostratigraphy for the Hettangian and Sinemurian can be made but the correlation with the northeuropean zonal divisions and chronostratigraphy is rather difficult. These are the only west mediterranean sections where a succession of Hettangian ammonite assemblages have been made. 相似文献