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71.
Miller JE Di Bilio AJ Wehbi WA Green MT Museth AK Richards JR Winkler JR Gray HB 《Biochimica et biophysica acta》2004,1655(1-3):59-63
Laser flash-quench methods have been used to generate tyrosine and tryptophan radicals in structurally characterized rhenium-modified Pseudomonas aeruginosa azurins. Cu(I) to "Re(II)" electron tunneling in Re(H107) azurin occurs in the microsecond range. This reaction is much faster than that studied previously for Cu(I) to Ru(III) tunneling in Ru(H107) azurin, suggesting that a multistep ("hopping") mechanism might be involved. Although a Y108 radical can be generated by flash-quenching a Re(H107)M(II) (M=Cu, Zn) protein, the evidence suggests that it is not an active intermediate in the enhanced Cu(I) oxidation. Rather, the likely explanation is rapid conversion of Re(II)(H107) to deprotonated Re(I)(H107 radical), followed by electron tunneling from Cu(I) to the hole in the imidazole ligand. 相似文献
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73.
Saliki JT Cooper EJ Rotstein DS Caseltine SL Pabst DA McLellan WA Govett P Harms C Smolarek KA Romero CH 《Journal of wildlife diseases》2006,42(1):142-148
An adult male Blainville's beaked whale (Mesoplodon densirostris) was found stranded on the Atlantic coast of the USA on 28 January 2004. Necropsy revealed a focal papilloma-like penile lesion, the cells from which revealed single 4-6 microm basophilic intranuclear inclusions. Total DNA extracted from lesion material was tested using a pan-herpes-virus PCR assay that targets the DNA polymerase gene and found to be positive. When the amplified DNA fragment was cloned, sequenced, and compared to GenBank-deposited herpesvirus DNA polymerase sequences, the detected virus was determined to be a distinct member of the Gammaherpesvirinae subfamily of herpesviruses. This new virus, tentatively named Ziphiid herpesvirus type 1, was associated with but not determined to be the cause of genital disease in the Blainville's beaked whale. 相似文献
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75.
William W. Driscoll Jennifer H. Wisecaver Jeremiah D. Hackett Noelle J. Espinosa Jared Padway Jessica E. Engers Jessica A. Bower 《Ecology letters》2023,26(5):677-691
Much of the evolutionary ecology of toxic algal blooms (TABs) remains unclear, including the role of algal toxins in the adaptive ‘strategies’ of TAB-forming species. Most eukaryotic TABs are caused by mixotrophs that augment autotrophy with organic nutrient sources, including competing algae (intraguild predation). We leverage the standing diversity of TABs formed by the toxic, invasive mixotroph Prymnesium parvum to identify cell-level behaviours involved in toxin-assisted predation using direct observations as well as comparisons between genetically distinct low- and high-toxicity isolates. Our results suggest that P. parvum toxins are primarily delivered at close range and promote subsequent prey capture/consumption. Surprisingly, we find opposite chemotactic preferences for organic (prey-derived) and inorganic nutrients between differentially toxic isolates, respectively, suggesting behavioural integration of toxicity and phagotrophy. Variation in toxicity may, therefore, reflect broader phenotypic integration of key traits that ultimately contribute to the remarkable flexibility, diversity, and success of invasive populations. 相似文献
76.
Forest succession in Kibale National Park, Uganda: implications for forest restoration and management 总被引:5,自引:1,他引:4
Jeremiah S. Lwanga 《African Journal of Ecology》2003,41(1):9-22
Forest succession was studied in four plots in former grasslands at the Ngogo study area in Kibale National Park, Uganda. The plots were located in areas that had been protected from fire for 0.58, 25, 9 and ≈30 years for plots 1, 2, 3 and 4, respectively. Species richness reflected the length of time that the plot had been protected from fire; it was highest in plot 4 and lowest in plot 1. Species density, stem density and basal area were all highest in plot 4 and lowest in plot 1. The species densities of plots 2 and 3 were not different. Similarly, plots 2 and 4 did not differ with regard to stem density or basal area. Animal seed dispersers played a vital role in the colonization of grasslands by forest tree species. 相似文献
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78.
Plass-Johnson Jeremiah G. Heiden Jasmin P. Abu Nur Lukman Muhammad Teichberg Mirta 《Coral reefs (Online)》2016,35(1):229-243
Coral Reefs - The composition of coral reef benthic communities is strongly affected by variation in water quality and consumer abundance and composition. This is particularly evident in highly... 相似文献
79.
Robert P. Sellers Leslie D. Alexander Victoria A. Johnson Chun-Chieh Lin Jeremiah Savage Ricardo Corral Jason Moss Tim S. Slugocki Erinprit K. Singh Melinda R. Davis Suchitra Ravula Jamie E. Spicer Jenna L. Oelrich Andrea Thornquist Chung-Mao Pan Shelli R. McAlpine 《Bioorganic & medicinal chemistry》2010,18(18):6822-6856
Utilizing the structure–activity relationship we have developed during the synthesis of the first two generations and mechanism of action studies that point to the interaction of these molecules with the key oncogenic protein Hsp90, we report here the design of 32 new Sansalvamide A derivatives and their synthesis. Our new structures, designed from previously reported potent compounds, were tested for cytotoxicity on the HCT116 colon cancer cell line, and their binding to the biological target was analyzed using computational studies involving blind docking of derivatives using Autodock. Further, we show new evidence that our molecules bind directly to Hsp90 and modulate Hsp90’s binding with client proteins. Finally, we demonstrate that we have integrated good ADME properties into a new derivative. 相似文献
80.
Radoshitzky SR Longobardi LE Kuhn JH Retterer C Dong L Clester JC Kota K Carra J Bavari S 《PloS one》2011,6(7):e21398
Machupo virus (MACV) is a highly pathogenic New World arenavirus that causes hemorrhagic fever in humans. MACV, as well as other pathogenic New World arenaviruses, enter cells after their GP1 attachment glycoprotein binds to their cellular receptor, transferrin receptor 1 (TfR1). TfR1 residues essential for this interaction have been described, and a co-crystal of MACV GP1 bound to TfR1 suggests GP1 residues important for this association. We created MACV GP1 variants and tested their effect on TfR1 binding and virus entry to evaluate the functional significance of some of these and additional residues in human and simian cells. We found residues R111, D123, Y122, and F226 to be essential, D155, and P160 important, and D114, S116, D140, and K169 expendable for the GP1-TfR1 interaction and MACV entry. Several MACV GP1 residues that are critical for the interaction with TfR1 are conserved among other New World arenaviruses, indicating a common basis of receptor interaction. Our findings also open avenues for the rational development of viral entry inhibitors. 相似文献