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961.
Bron PA Meijer M Bongers RS de Vos WM Kleerebezem M 《Journal of applied microbiology》2007,103(5):1424-1434
AIM: This study aims to evaluate the impact of mutation of previously identified in vivo-induced (ivi) genes on the persistence and survival of Lactobacillus plantarum WCFS1 in the gastrointestinal (GI) tract of mice. METHODS AND RESULTS: Nine Lact. plantarum ivi gene replacement mutants were constructed, focussing on ivi genes that encode proteins with a predicted role in cell envelope functionality, stress response and regulation. The in vitro growth characteristics of the mutants appeared identical to those observed for the wild-type strain, which agrees with the recombination-based in vivo expression technology suggestion that these genes are not transcribed in the laboratory. Quantitative PCR experiments demonstrated differences in the relative population dynamics of the Lact. plantarum ivi mutants in faecal samples after passage through the GI tract of mice. CONCLUSIONS: The in situ competition experiments revealed a 100- to 1000-fold reduction of the relative abundance of three of the ivi gene mutants, harbouring deletions of genes predicted to encode a copper transporter, an orphan IIC cellobiose PTS and a cell wall anchored extracellular protein. SIGNIFICANCE AND IMPACT OF THE STUDY: These experiments clearly establish that the proteins encoded by these three genes play a key role in Lact. plantarum performance during passage of the GI tract. 相似文献
962.
Drévillon L Tanguy G Hinzpeter A Arous N de Becdelièvre A Aissat A Tarze A Goossens M Fanen P 《PloS one》2011,6(3):e18334
The CFTR (cystic fibrosis transmembrane conductance regulator) protein is a large polytopic protein whose biogenesis is inefficient. To better understand the regulation of CFTR processing and trafficking, we conducted a genetic screen that identified COMMD1 as a new CFTR partner. COMMD1 is a protein associated with multiple cellular pathways, including the regulation of hepatic copper excretion, sodium uptake through interaction with ENaC (epithelial sodium channel) and NF-kappaB signaling. In this study, we show that COMMD1 interacts with CFTR in cells expressing both proteins endogenously. This interaction promotes CFTR cell surface expression as assessed by biotinylation experiments in heterologously expressing cells through regulation of CFTR ubiquitination. In summary, our data demonstrate that CFTR is protected from ubiquitination by COMMD1, which sustains CFTR expression at the plasma membrane. Thus, increasing COMMD1 expression may provide an approach to simultaneously inhibit ENaC absorption and enhance CFTR trafficking, two major issues in cystic fibrosis. 相似文献
963.
F. M. van de Sandt S. M. Boekholdt B. J. Bouma M. Groenink A. P. C. M. Backx D. R. Koolbergen R. J. de Winter B. J. M. Mulder 《Netherlands heart journal》2011,19(6):297-300
Patent ductus arteriosus (PDA) is a rare diagnosis in adults, since symptoms and signs usually occur in infancy and most cases are treated shortly after diagnosis. We present two patients who were first diagnosed with PDA during adulthood. The first case represents a more severe form of PDA, where the need for closure of the PDA is obvious. In the second case the sequelae of the PDA are less clear. In both patients, closure of the PDA (surgically in one case, percutaneously in the other) was successful. 相似文献
964.
Dereplication by HPLC‐DAD‐ESI‐MS/MS and Screening for Biological Activities of Byrsonima Species (Malpighiaceae) 下载免费PDF全文
965.
Janaine Almeida Neto Daniel Amando Nery Katia Simoni Bezerra Lima Maria Eduarda Gomes da Cruz Silva Tarcísio Cícero de Lima Araújo Nathália Andrezza Carvalho de Souza Rodolfo Hideki Vicente Nishimura Camila de Souza Araújo Ana Paula de Oliveira Jackson Roberto Guedes da Silva Almeida Larissa Araújo Rolim 《化学与生物多样性》2023,20(3):e202201039
This article describes the phytochemical study of Cannabis sativa roots from northeastern Brazil. The dried plant material was pulverized and subjected to exhaustive maceration with ethanol at room temperature, obtaining the crude ethanolic extract (Cs-EEBR). The volatile compounds were analyzed by gas chromatography coupled with mass spectrometry (GC/MS), which allowed to identify 22 compounds by comparing the linear retention index (LRI), the similarity index (SI) and the fragmentation pattern of the constituents with the literature. By this technique the major compounds identified were: friedelan-3-one and β-sitosterol. In addition, two fractions were obtained from Cs-EEBR by classical column chromatography and preparative thin layer chromatography. These fractions were analyzed by NMR and IR and together with the mass spectrometry data allowed to identify the compounds: epifriedelanol, friedelan-3-one, β-sitosterol and stigmasterol. The study contributed to the phytochemical knowledge of Cannabis sativa, specifically the roots, as there are few reports on the chemical constituents of this part of the plant. 相似文献
966.
Comparative proteomic analysis of Xanthomonas citri ssp. citri periplasmic proteins reveals changes in cellular envelope metabolism during in vitro pathogenicity induction 下载免费PDF全文
Juliana Artier Flávia da Silva Zandonadi Flávia Maria de Souza Carvalho Bianca Alves Pauletti Adriana Franco Paes Leme Carolina Moretto Carnielli Heloisa Sobreiro Selistre‐de‐Araujo Maria Célia Bertolini Jesus Aparecido Ferro José Belasque Júnior Julio Cezar Franco de Oliveira Maria Teresa Marques Novo‐Mansur 《Molecular Plant Pathology》2018,19(1):143-157
Citrus canker is a plant disease caused by Gram‐negative bacteria from the genus Xanthomonas. The most virulent species is Xanthomonas citri ssp. citri (XAC), which attacks a wide range of citrus hosts. Differential proteomic analysis of the periplasm‐enriched fraction was performed for XAC cells grown in pathogenicity‐inducing (XAM‐M) and pathogenicity‐non‐inducing (nutrient broth) media using two‐dimensional electrophoresis combined with liquid chromatography‐tandem mass spectrometry. Amongst the 40 proteins identified, transglycosylase was detected in a highly abundant spot in XAC cells grown under inducing condition. Additional up‐regulated proteins related to cellular envelope metabolism included glucose‐1‐phosphate thymidylyltransferase, dTDP‐4‐dehydrorhamnose‐3,5‐epimerase and peptidyl‐prolyl cis–trans‐isomerase. Phosphoglucomutase and superoxide dismutase proteins, known to be involved in pathogenicity in other Xanthomonas species or organisms, were also detected. Western blot and quantitative real‐time polymerase chain reaction analyses for transglycosylase and superoxide dismutase confirmed that these proteins were up‐regulated under inducing condition, consistent with the proteomic results. Multiple spots for the 60‐kDa chaperonin and glyceraldehyde‐3‐phosphate dehydrogenase were identified, suggesting the presence of post‐translational modifications. We propose that substantial alterations in cellular envelope metabolism occur during the XAC infectious process, which are related to several aspects, from defence against reactive oxygen species to exopolysaccharide synthesis. Our results provide new candidates for virulence‐related proteins, whose abundance correlates with the induction of pathogenicity and virulence genes, such as hrpD6, hrpG, hrpB7, hpa1 and hrpX. The results present new potential targets against XAC to be investigated in further functional studies. 相似文献
967.
Genaina Aparecida de Souza Denise Cunha Fernandes dos Santos Dias Thaline Martins Pimenta Andrea Lanna Almeida Edgard Augusto de Toledo Picoli Antônio de Pádua Alvarenga José Cleydson Ferreira da Silva 《Physiologia plantarum》2018,162(4):495-505
Changes in the concentration of sugars and sucrose metabolism enzymes can characterize the developmental stages of a seed. In recalcitrant species such as Hevea brasiliensis L., little is known about these changes. We aimed to evaluate the three main stages of development of rubber tree seeds – histodifferentiation, cell elongation and accumulation of reserves. The activities of acid and neutral invertases (E.C. 3.2.1.26) and sucrose synthase (EC 2.4.1.13), and the concentrations of reducing sugars (RS), total soluble sugars (TSS) and sucrose (Suc) were determined concomitantly with the histochemical and anatomical evaluation of seed structure. Histodifferentiation in rubber tree seeds occurs up to 75 days after anthesis (DAA). The concentration of RS is high and of Suc is low during seed histodifferentiation, which occurs along with a visible increase in the number of cell divisions. After that period, there is an increase in the concentration of Suc (mg g?1) and in the number and size of starch granules, and a decrease in the concentration of RS (mg g?1). At that point, cell elongation occurs. At 135 DAA, there is an inversion in the concentration of these two sugars and an increase in reserve accumulation. Thus, in seeds of the evaluated clone, the period up to 75 DAA is characterized as the histodifferentiation stage, while from that time up to 120 DAA the cell elongation stage takes place. The final stage of seed maturation and reserve accumulation begins at 135 DAA, and the seed, including the embryo, is completely formed at 175 DAA. 相似文献
968.
969.
970.
Leng Yu Wang Hao de Lucio Mario Gomez Hector 《Biomechanics and modeling in mechanobiology》2022,21(6):1825-1840
Biomechanics and Modeling in Mechanobiology - Subcutaneous injection of therapeutic monoclonal antibodies (mAbs) has gained increasing interest in the pharmaceutical industry. The transport,... 相似文献