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471.
Dr. Eric K. W. Tam Dr. Tuan Minh Nguyen Cheryl Z. H. Lim Puay Leng Lee Zhimei Li Xia Jiang Dr. Sridhar Santhanakrishnan Tiong Wei Tan Yi Ling Goh Sze Yue Wong Haiyan Yang Esther H. Q. Ong Dr. Jeffrey Hill Dr. Qiang Yu Prof. Christina L. L. Chai 《ChemMedChem》2015,10(1):173-182
3‐Deazaneplanocin A (DzNep) is a potential epigenetic drug for the treatment of various cancers. DzNep has been reported to deplete histone methylations, including oncogenic EZH2 complex, giving rise to epigenetic modifications that reactivate many silenced tumor suppressors in cancer cells. Despite its promise as an anticancer drug, little is known about the structure–activity relationships of DzNep in the context of epigenetic modifications and apoptosis induction. In this study, a number of analogues of DzNep were examined for DzNep‐like ability to induce synergistic apoptosis in cancer cells in combination with trichostatin A, a known histone deacetylase (HDAC) inhibitor. The structure–activity relationship data thus obtained provide valuable information on the structural requirements for biological activity. The studies identified three compounds that show similar activities to DzNep. Two of these compounds show good pharmacokinetics and safety profiles. Attempts to correlate the observed synergistic apoptotic activities with measured S‐adenosylhomocysteine hydrolase (SAHH) inhibitory activities suggest that the apoptotic activity of DzNep might not be directly due to its inhibition of SAHH. 相似文献
472.
Friederike I. Nollmann Antje K. Heinrich Alexander O. Brachmann Christophe Morisseau Krishnendu Mukherjee Ángel M. Casanova‐Torres Frederic Strobl David Kleinhans Sebastian Kinski Katharina Schultz Michael L. Beeton Marcel Kaiser Ya‐Yun Chu Long Phan Ke Aunchalee Thanwisai Kenan A. J. Bozhüyük Narisara Chantratita Prof. Dr. Friedrich Götz Prof. Nick R. Waterfield Prof. Dr. Andreas Vilcinskas Prof. Dr. Ernst H. K. Stelzer Prof. Dr. Heidi Goodrich‐Blair Prof. Dr. Bruce D. Hammock Prof. Dr. Helge B. Bode 《Chembiochem : a European journal of chemical biology》2015,16(5):766-771
Simple urea compounds (“phurealipids”) have been identified from the entomopathogenic bacterium Photorhabdus luminescens, and their biosynthesis was elucidated. Very similar analogues of these compounds have been previously developed as inhibitors of juvenile hormone epoxide hydrolase (JHEH), a key enzyme in insect development and growth. Phurealipids also inhibit JHEH, and therefore phurealipids might contribute to bacterial virulence. 相似文献
473.
Lars M Mogren Marie E Olsson Ulla E Gertsson 《Journal of the science of food and agriculture》2007,87(8):1595-1602
Storage experiments with commercial cultivars of onion (Allium cepa L.) were performed at low constant temperature (1°C) and at higher variable temperature (~8°C). Cultivar differences in quercetin glucoside content were significant, but neither nitrogen fertiliser level nor lifting time had more than minor effects at start of storage or after 3 or 5 months of storage. The role of onion size for quercetin glucoside content and composition was inconsistent but seemed to be of minor importance. Irrespective of storage conditions, the content of quercetin glucosides only showed minor reduction and the composition was unchanged. After 5 months of storage, onion sprouting was recorded during a shelf‐life period of 9 weeks at room temperature. Early lifting resulted in onions with low sprouting and good storage abilities without negative effects on quercetin glucoside content. The results suggest that it may be possible to minimise nitrogen fertiliser levels without negative effects on onion yield, quercetin glucoside content or storage capacity. Copyright © 2007 Society of Chemical Industry 相似文献
474.
Guo CF Zhang LW Han X Li JY Du M Yi HX Feng Z Zhang YC Xu XR 《Journal of dairy science》2011,94(4):1732-1737
A sensitive protocol based on thin-layer chromatography (TLC) was developed to screen qualitatively bile salt hydrolase (BSH)-active lactobacilli. The sodium salts of glycocholic acid and taurocholic acid were used as substrates, and bacterial BSH activity was confirmed by detecting cholic acid as a product of the bile conjugates using a TLC assay with direct visual observation. Forty-five lactobacilli isolated from human fecal samples were tested for BSH activity by the TLC assay, a conventional plate assay, and a quantitative colorimetric assay. With the TLC and quantitative colorimetric assays, the same 24 BSH-positive strains were detected. No false-positive or false-negative results were detected by the TLC assay. However, only 20 BSH-positive strains were detected with the conventional plate assay. Compared with the conventional plate assay, the TLC assay is more sensitive for the detection of BSH activity of lactobacilli and, thus, more suitable for screening of BSH-active lactobacilli of human origin. 相似文献
475.
476.
Mutamed M. Ayyash Abdelmoneim K. Abdalla Nadia S. AlKalbani Mohd Affan Baig Mark S. Turner Shao-Quan Liu Nagendra P. Shah 《Journal of dairy science》2021,104(8):8363-8379
The selection of potential probiotic strains that possess the physiological capacity of performing successfully in the gastrointestinal tract (GIT) is a critical challenge. Probiotic microorganisms must tolerate the deleterious effects of various stresses to survive passage and function in the human GIT. Adhesion to the intestinal mucosa is also an important aspect. Recently, numerous studies have been performed concerning the selection and evaluation of novel probiotic microorganisms, mainly probiotic bacteria isolated from dairy and nondairy products. Therefore, it would be crucial to critically review the assessment methods employed to select the potential probiotics. This article aims to review and discuss the recent approaches, methods used for the selection, and outcomes of the evaluation of novel probiotic strains with the main purpose of supporting future probiotic microbial assessment studies. The findings and approaches used for assessing acid tolerance, bile metabolism and tolerance, and adhesion capability are the focus of this review. In addition, probiotic bile deconjugation and bile salt hydrolysis are explored. The selection of a new probiotic strain has mainly been based on the in vitro tolerance of physiologically related stresses including low pH and bile, to ensure that the potential probiotic microorganism can survive the harsh conditions of the GIT. However, the varied experimental conditions used in these studies (different types of media, bile, pH, and incubation time) hamper the comparison of the results of these investigations. Therefore, standardization of experimental conditions for characterizing and selecting probiotics is warranted. 相似文献
477.
Piotr Henryk Maecki Pawe Mitkowski Elbieta Jagielska Karolina Trochimiak Stphane Mesnage Izabela Sabaa 《International journal of molecular sciences》2021,22(13)
The best-characterized members of the M23 family are glycyl-glycine hydrolases, such as lysostaphin (Lss) from Staphylococcus simulans or LytM from Staphylococcus aureus. Recently, enzymes with broad specificities were reported, such as EnpACD from Enterococcus faecalis, that cleaves D,L peptide bond between the stem peptide and a cross-bridge. Previously, the activity of EnpACD was demonstrated only on isolated peptidoglycan fragments. Herein we report conditions in which EnpACD lyses bacterial cells live with very high efficiency demonstrating great bacteriolytic potential, though limited to a low ionic strength environment. We have solved the structure of the EnpACD H109A inactive variant and analyzed it in the context of related peptidoglycan hydrolases structures to reveal the bases for the specificity determination. All M23 structures share a very conserved β-sheet core which constitutes the rigid bottom of the substrate-binding groove and active site, while variable loops create the walls of the deep and narrow binding cleft. A detailed analysis of the binding groove architecture, specificity of M23 enzymes and D,L peptidases demonstrates that the substrate groove, which is particularly deep and narrow, is accessible preferably for peptides composed of amino acids with short side chains or subsequent L and D-isomers. As a result, the bottom of the groove is involved in interactions with the main chain of the substrate while the side chains are protruding in one plane towards the groove opening. We concluded that the selectivity of the substrates is based on their conformations allowed only for polyglycine chains and alternating chirality of the amino acids. 相似文献
478.
Artur Pinski Alexander Betekhtin Bozena Skupien-Rabian Urszula Jankowska Elisabeth Jamet Robert Hasterok 《International journal of molecular sciences》2021,22(13)
High temperature stress leads to complex changes to plant functionality, which affects, i.a., the cell wall structure and the cell wall protein composition. In this study, the qualitative and quantitative changes in the cell wall proteome of Brachypodium distachyon leaves in response to high (40 °C) temperature stress were characterised. Using a proteomic analysis, 1533 non-redundant proteins were identified from which 338 cell wall proteins were distinguished. At a high temperature, we identified 46 differentially abundant proteins, and of these, 4 were over-accumulated and 42 were under-accumulated. The most significant changes were observed in the proteins acting on the cell wall polysaccharides, specifically, 2 over- and 12 under-accumulated proteins. Based on the qualitative analysis, one cell wall protein was identified that was uniquely present at 40 °C but was absent in the control and 24 proteins that were present in the control but were absent at 40 °C. Overall, the changes in the cell wall proteome at 40 °C suggest a lower protease activity, lignification and an expansion of the cell wall. These results offer a new insight into the changes in the cell wall proteome in response to high temperature. 相似文献
479.
480.
阐述了胆盐水解酶(BSH)的功能、特性以及对宿主微生物产生的影响;介绍了胆盐水解酶基因、基因调节及同系物;讨论了胆盐水解酶未来研究方向和应用的前景。 相似文献