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71.
Marlene Adlhart Florian Poetsch Mario Hlevnjak Megan Hoogmoed Anton
A Polyansky Bojan Zagrovic 《Nucleic acids research》2022,50(7):4054
During packaging in positive-sense single-stranded RNA (+ssRNA) viruses, coat proteins (CPs) interact directly with multiple regions in genomic RNA (gRNA), but the underlying physicochemical principles remain unclear. Here we analyze the high-resolution cryo-EM structure of bacteriophage MS2 and show that the gRNA/CP binding sites, including the known packaging signal, overlap significantly with regions where gRNA nucleobase-density profiles match the corresponding CP nucleobase-affinity profiles. Moreover, we show that the MS2 packaging signal corresponds to the global minimum in gRNA/CP interaction energy in the unstructured state as derived using a linearly additive model and knowledge-based nucleobase/amino-acid affinities. Motivated by this, we predict gRNA/CP interaction sites for a comprehensive set of 1082 +ssRNA viruses. We validate our predictions by comparing them with site-resolved information on gRNA/CP interactions derived in SELEX and CLIP experiments for 10 different viruses. Finally, we show that in experimentally studied systems CPs frequently interact with autologous coding regions in gRNA, in agreement with both predicted interaction energies and a recent proposal that proteins in general tend to interact with own mRNAs, if unstructured. Our results define a self-consistent framework for understanding packaging in +ssRNA viruses and implicate interactions between unstructured gRNA and CPs in the process. 相似文献
72.
Read at the First Congress of the International Society for Tropical Dermatology, Naples, June 8–13, 1964. 相似文献
73.
Mario J. A. Bick 《American anthropologist》1963,65(5):1146-1147
74.
Mare K. Saba-El-Leil Sylvain Rivard David Morse Mario Cappadocia 《Plant molecular biology》1994,24(4):571-583
A genomic clone of the S11 allele from the self-incompatibility locus (S locus) in Solanum chacoense Bitt. has been isolated by cross-hybridization to the S. chacoense S13 allele and sequenced. The sequence of the S11 allele contains all the features expected for S genes of the Solanaceae, and S11 expression, as assessed by northern blots and RNA-PCR, was similar to that of other S. chacoense S alleles. The S11 protein sequence shares 95% identity with the phenotypically distinct S13 protein of S. chacoense and is the gametophytic S allele with the highest similarity to an existing allele so far discovered. Only 10 amino acid changes differentiate the mature proteins from these two alleles, which sets a new lower limit to the number of changes that can produce an altered S allele specificity. The amino acid substitutions are not clustered, suggesting that an accumulation of random point mutations can generate S allele diversity. The S11 intron is unusual in that it could be translated in frame with the coding sequence, thus suggesting an additional mechanism for the generation of new S alleles. 相似文献
75.
On the Effect of Prevalent Carbazole Homocoupling Defects on the Photovoltaic Performance of PCDTBT:PC71BM Solar Cells 下载免费PDF全文
Florian Lombeck Hartmut Komber Daniele Fazzi Diego Nava Jochen Kuhlmann Dominik Stegerer Karen Strassel Josef Brandt Amaia Diaz de Zerio Mendaza Christian Müller Walter Thiel Mario Caironi Richard Friend Michael Sommer 《Liver Transplantation》2016,6(21)
The photophysical properties and solar cell performance of the classical donor–acceptor copolymer PCDTBT (poly(N‐9′‐heptadecanyl‐2,7‐carbazole‐alt ‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole))) in relation to unintentionally formed main chain defects are investigated. Carbazole–carbazole homocouplings (Cbz hc) are found to significant extent in PCDTBT made with a variety of Suzuki polycondensation conditions. Cbz hc vary between 0 and 8 mol% depending on the synthetic protocol used, and are quantified by detailed nuclear magnetic resonance spectroscopy including model compounds, which allows to establish a calibration curve from optical spectroscopy. The results are corroborated by extended time‐dependent density functional theory investigations on the structural, electronic, and optical properties of regularly alternating and homocoupled chains. The photovoltaic properties of PCDTBT:fullerene blend solar cells significantly depend on the Cbz hc content for constant molecular weight, whereby an increasing amount of Cbz hc leads to strongly decreased short circuit currents JSC. With increasing Cbz hc content, JSC decreases more strongly than the intensity of the low energy absorption band, suggesting that small losses in absorption cannot explain the decrease in JSC alone, rather than combined effects of a more localized LUMO level on the TBT unit and lower hole mobilities found in highly defective samples. Homocoupling‐free PCDTBT with optimized molecular weight yields the highest efficiency up to 7.2% without extensive optimization. 相似文献
76.
77.
Ellen De Backer Rita Verhelst Hans Verstraelen Mohammed A Alqumber Jeremy P Burton John R Tagg Marleen Temmerman Mario Vaneechoutte 《BMC microbiology》2007,7(1):115
Background
Most studies of the vaginal microflora have been based on culture or on qualitative molecular techniques. Here we applied existing real-time PCR formats forLactobacillus crispatus,L. gasseriandGardnerella vaginalisand developed new formats forAtopobium vaginae,L. inersandL. jenseniito obtain a quantitative non culture-based determination of these species in 71 vaginal samples from 32 pregnant and 28 non-pregnant women aged between 18 and 45 years. 相似文献78.
79.
80.
Jiaqiang Cai D. Jonathan Bennett Zoran Rankovic Maureen Dempster Xavier Fradera Jonathan Gillespie Iain Cumming William Finlay Mark Baugh Sylviane Boucharens John Bruin Kenneth S. Cameron William Hamilton Jennifer Kerr Emma Kinghorn George McGarry John Robinson Paul Scullion Joost C.M. Uitdehaag Mario van Zeeland Eric Nicolai 《Bioorganic & medicinal chemistry letters》2010,20(15):4447-4450
Starting from previously disclosed equally potent cathepsin K and S inhibitor 4-propyl-6-(3-trifluoromethylphenyl)pyrimidine-2-carbonitrile 1, a novel 2-phenyl-9H-purine-6-carbonitrile scaffold was identified to provide potent and selective cathepsin S inhibitors. 相似文献