摘要：

Crystal structures of the native HIV-1 proteinase and an A71TN82A mutant have been solved in complexes with a symmetric aminodiol inhibitor, BMS-182193. Some of the conformational differences between these two complexes can be traced to their non-isomorphous crystal forms, but numerous rearrangements due to mutations are clearly visible. The V82A mutation creates more space at the periphery of the active site cleft, allowing distal parts of the inhibitor to move more freely, whereas the non-active-site mutation A71T stabilizes the enzyme backbone. The role of mutations in eliciting drug resistance is discussed.: The impact of protozoan predation of bacteria on the mineralization of N from bacterial cells in soil is reviewed. The discussion is focussed on soil microorganisms as both a source and a sink for N during microbial biomass turnover. This renders...: Plagiognathus (Poliopterua) ovatulus from Dalmatia, and Campylomma novaki, closely related with C. verbasci M. D., from Dalmatia are described and figured.: Examination of faecal samples from 150 Chinese-born residents of New York City, USA, revealed ova of Clonorchis sinensis in 26.0%. 6 other species or genera of parasites were recorded but were uncommon. Most of the infected immigrants were from Kw...: Serum samples (67) from individuals living in a malaria endemic area and 60 sera from healthy blood donors living in Bangkok [Thailand] (non-malarious area) were tested for growth inhibition activity against 3 strains (SO, SN and G-112) of P. falc...: Posttranslational modifications of histones are involved in regulation of chromatin structure and gene activity. Whereas the modifications of the core histones H2A, H2B, H3, and H4 have been extensively studied, our knowledge of H1 modifications...: Dormant-budded Gloria' azaleas (Rhododendron sp.) at various maturity levels (one, eight, or 32 individual open flowers) were moved from the greenhouse to postproduction rooms. Postproduction rooms were maintained at 21 .+-. 1C, relative humidity...: In milk, the correlation between oxidized flavour defects and content of polyunsaturated fatty acids was investigated, with reference to xanthine oxidase and phosphatase activities, skim-milk turbidity and the number of fat globules. Daily additio...: Lactate-fermenting sarcinas were found to predominate among the lactate-fermenting bacteria in the rumen of cows fed silage as the main roughage source but other dietary constituents had an influence. A problem of retaining viability of sarcina is...: New locality of Chimaphila umbellata (L.) Barton has been found in Nova Cerkev near Vojnik within the Myrtillo-Pinetum austroalpinum Tomazic 42 association.: Melatonin rhythms were assessed in 49 registered blind individuals by measurement of the urinary metabolite of melatonin, 6-sulfatoxymelatonin (aMT6s). Subjects had different causes of visual loss and were classified as having light perception or...: A mammalian protein involved in receptor-mediated endocytosis specifically binds to phosphatidylinositol 3-kinase. More specifically it binds to the Bcr homology domain of the p85 subunit of phosphatidylinositol 3-kinase. Phathoidylinositol 3-kina...

展开