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1.
Two protein bands with laccase activity were found after PAGE of culture liquid or mycelium extract of Pleurotus eryngii, grown on glucose–ammonium tartrate–yeast extract medium with and without inducers. A major and a minor laccase band were
observed in the basal medium. The intensity of the major band (laccase I) did not change after the addition of inducers. However,
the minor band (laccase II), characterized by higher electrophoretic mobility, was strongly induced by wheat–straw alkalilignin
and vanillic and veratric acids. Laccase activity in the basal medium had an optimum pH of 4.5 and was stable from pH 3 to
10 during 24 h at room temperature. This enzyme had wide substrate specificity on hydroquinones, methoxy-substituted monophenols,
and aromatic amines. In general, laccase activity was found only with compounds having a redox potential lower than 0.5 mV.
The highest activity was obtained with methoxy- and methyl-substituted p-hydroquinones and aromatic diamines. Some activity also occurred with the aliphatic compound 3,5-cyclohexadiene-1,2-diol.
Received: 22 April 1996 / Accepted: 29 June 1996 相似文献
2.
Differences in the Detection of BrdU/EdU Incorporation Assays Alter the Calculation for G1, S,and G2 Phases of the Cell Cycle in Trypanosomatids 下载免费PDF全文
Marcelo Santos da Silva Paula Andrea Marin Muñoz Hugo Aguirre Armelin Maria Carolina Elias 《The Journal of eukaryotic microbiology》2017,64(6):756-770
Trypanosomatids are the etiologic agents of various infectious diseases in humans. They diverged early during eukaryotic evolution and have attracted attention as peculiar models for evolutionary and comparative studies. Here, we show a meticulous study comparing the incorporation and detection of the thymidine analogs BrdU and EdU in Leishmania amazonensis, Trypanosoma brucei, and Trypanosoma cruzi to monitor their DNA replication. We used BrdU‐ and EdU‐incorporated parasites with the respective standard detection approaches: indirect immunofluorescence to detect BrdU after standard denaturation (2 M HCl) and “click” chemistry to detect EdU. We found a discrepancy between these two thymidine analogs due to the poor detection of BrdU, which is reflected on the estimative of the duration of the cell cycle phases G1, S, and G2. To solve this discrepancy, we increase the exposure of incorporated BrdU using different concentrations of HCl. Using a new value for HCl concentration, we re‐estimated the phases G1, S, G2 + M, and cytokinesis durations, confirming the values found by this approach using EdU. In conclusion, we suggest that the studies using BrdU with standard detection approach, not only in trypanosomatids but also in others cell types, should be reviewed to ensure an accurate estimation of DNA replication monitoring. 相似文献
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L.E. Palma-Cano H.A. Piñon-Castillo S.H. Tarango-Rivero A. Carbon J. Salas-Leiva L.N. Muñoz-Castellanos C. Cravo-Laureau R. Duran E. Orrantia-Borunda 《Letters in applied microbiology》2021,72(5):556-569
We described the bacterial diversity of walnut grove soils under organic and conventional farming. The bacterial communities of rhizospheric and nonrhizospheric soils of pecan tree (Carya illinoensis K. Koch) were compared considering two phenological stages (sprouting and ripening). Sixteen operational taxonomic units (OTUs) were identified significantly more abundant according to the plant development, only one according to the farming condition, and none according to the soil origin. The OTUs specificaly abundant according to plant development included Actinobateria (2) and Betaproteobacteria (1) related OTUs more abundant at the sprouting stage, while at the fruit ripening (FR) stage the more abundant OTUs were related to Actinobacteria (6), Alphaproteobacteria (6), and unclassified Bacteria (1). The Gaiellaceae OTU18 (Actinobacteria) was more abundant under conventional farming. Thus, our study revealed that the plant development stage was the main factor shaping the bacterial community structure, while less influence was noticed for the farming condition. The bacterial communities exhibited specific metabolic capacities, a large range of carbon sources being used at the FR stage. The identified OTUs specifically more abundant represent indicators providing useful information on soil condition, potential tools for the management of soil bacterial communities. 相似文献
6.
Manuel Algara Meritxell Arenas Dolores De las Peñas Eloisa Bayo Julia Muñoz José Antonio Carceller Juan Salinas Ferran Moreno Francisco Martínez Ezequiel González Ángel Montero 《Reports of Practical Oncology and Radiotherapy》2012,17(3):122-128
AimTo evaluate the resources and techniques used in the irradiation of patients with breast cancer after lumpectomy or mastectomy and the status of implementation of new techniques and therapeutic schedules in our country.BackgroundThe demand for cancer care has increased among the Spanish population, as long as cancer treatment innovations have proliferated. Radiation therapy in breast cancer has evolved exponentially in recent years with the implementation of three-dimensional conformal radiotherapy, intensity modulated radiotherapy, image guided radiotherapy and hypofractionation.Material and MethodsAn original survey questionnaire was sent to institutions participating in the SEOR-Mama group (GEORM). In total, the standards of practice in 969 patients with breast cancer after surgery were evaluated.ResultsThe response rate was 70% (28/40 centers). In 98.5% of cases 3D conformal treatment was used. All the institutions employed CT-based planning treatment. Boost was performed in 56.4% of patients: electrons in 59.8%, photons in 23.7% and HDR brachytherapy in 8.8%. Fractionation was standard in 93.1% of patients. Supine position was the most frequent. Only 3 centers used prone position. The common organs of risk delimited were: homolateral lung (80.8%) and heart (80.8%). In 84% histograms were used. An 80.8% of the centers used isocentric technique. In 62.5% asymmetric fields were employed. CTV was delimited in 46.2%, PTV in 65% and both in 38.5%. A 65% of the centers checked with portal films. IMRT and hypofractionation were used in 1% and in 5.5% respectively.ConclusionIn most of centers, 3D conformal treatment and CT-based planning treatment were used. IMRT and hypofractionation are currently poorly implemented in Spain. 相似文献
7.
Dewen Tong Jinyi Wang Peihong Mu Qiang Dong Baoyu Zhao Wenming Liu Jun Zhao Li Li Tao Zhou 《Animal Feed Science and Technology》2008,142(1-2):74-88
Locoweeds cause significant livestock poisoning and economic loss all over the world. The purpose of this study was to evaluate the immune effect of locoweed toxin, swainsonine (SW), and human serum albumin (HSA) immunoconjugate (SW–HSA) on goats. Twenty four Sannon goats were randomly separated into immune control group, immune poisoning group I, immune poisoning group II and poisoning control group. Immune control group, immune poisoning group I and II were first vaccinated with SW–HSA immunoconjugate. Then, the poisoning control group, immune poisoning group I and II were fed with 10.0 g/kg BW/d dry powder of Oxytropis kansuensis Bunge in every morning and the duration of poisoning was 80 days. The immune control group was supplied with an alfalfa-based diet. Blood samples of these experimental animals were collected every 7 days after poisoning, and the serum enzymes α-mannosidase (AMA), lactate dehydrogenase (LDH), alkaline phosphatase (AKP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and blood urea nitrogen (BUN) were analyzed. Comparing with the poisoning control group, the changes of serum LDH, AKP, AST, AMA and BUN level of the two immune groups (I and II) were delayed 28, 14, 28, 21, 14 days, respectively, which indicated that SW–HSA immunoconjugate could prevent tissues containing BUN and these serum enzymes of the experimental animals from Oxytropis kansuensis Bunge injuring during these days. In the whole study, SW–HSA immunoconjugate and swainsonine did not influence serum ALT levels of the experimental goats. 相似文献
8.
Carlos Rico José Luis Rico Noelia Muñoz Beatriz Gómez Iñaki Tejero 《Engineering in Life Science》2011,11(5):476-481
The effect of mixing on biogas production of a 1.5‐m3 pilot continuous stirred tank reactor (CSTR) processing screened dairy manure was evaluated. Mixing was carried out by recirculation of reactor content with a mono pump. The experiment was conducted at a controlled temperature of 37±1°C and hydraulic retention times (HRTs) of 20 and 10 days. The effect of continuous and intermittent operation of the recirculation pump on biogas production was studied. At 10 days of HRT, the results showed a minimal influence of recirculation rate on biogas production and that continuous recirculation did not improve reactor performance. At 20 days of HRT, the recirculation rate did not affect reactor performance. Combination of low solid content in feed animal slurry and long HRTs results in minimal mixing requirements for anaerobic digestion. 相似文献
9.
Francisco J Gálvez-Gastélum Aida A Segura-Flores María D Senties-Gomez Jose F Muñoz-Valle Juan S Armendáriz-Borunda 《Journal of biomedical science》2010,17(1):42
Background
Liver fibrosis ranks as the second cause of death in México's productive-age population. This pathology is characterized by acummulation of fibrillar proteins in hepatic parenchyma causing synthetic and metabolic disfunction. Remotion of excessive fibrous proteins might result in benefit for subjects increasing survival index. The goal of this work was to find whether the already known therapeutical effect of human urokinase Plasminogen Activator and human Matrix Metalloprotease 8 extends survival index in cirrhotic animals. 相似文献10.
Ye Yu Xiao-Jing Liu Xiao Ma Zhong-Jie Zhang Tai-Chu Wang Fan Sun Cheng-Xiang Hou Mu-Wang Li 《Insect Science》2020,27(1):2-13
The silkworm Bombyx mori is an important lepidopteran model insect in which many kinds of natural mutants have been identified.However,molecular mechanisms of most of these mutants remain to be explored.Here we report the identification of a gene Bm-app is responsible for the silkworm minute wing(mw)mutation which exhibits exceedingly small wings during pupal and adult stages.Compared with the wild type silkworm,relative messenger RNA expression of Bm-app is significantly decreased in the ul 1 mutant strain which shows mw phenotype.A 10 bp insertion in the putative promoter region of the Bm-app gene in mw mutant strain was identified and the dual luciferase assay revealed that this insertion decreased Bm-app promoter activity.Furthermore,clustered regularly interspaced short palindromic repeats/RNA-guided Cas9 nucleases-mediated depletion of the Bm-app induced similar wing defects which appeared in the mw mutant,demonstrating that Bm-app controls wing development in B.mori.Bm-app encodes a palmitoyltransferase and is responsible for the palmitoylation of selected cytoplasmic proteins,indicating that it is required for cell mitosis and growth during wing development.We also discuss the possibility that Bm-app regulates wing development through the Hippo signaling pathway in B.mori. 相似文献