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排序方式: 共有4787条查询结果,搜索用时 62 毫秒
941.
Lucia Banci I. Bertini G. Quacquarini Olaf Walter Antonio Díaz Manuel Hervás Miguel A. de la Rosa 《Journal of biological inorganic chemistry》1996,1(4):330-340
The three-dimensional structure in solution of the reduced form of cytochrome c
6 from the green alga Monoraphidium braunii has been solved through NMR data. Cytochrome c
6 acts as a small mono-heme electron carrier protein between the two membrane-embedded complexes cytochrome f and photosystem I. The structure was determined using 1278 relevant interproton NOEs out of 1776 assigned NOEs with distance
geometry (DG) calculations which included 36 stereospecific assignments and 20 experimentally found angle constraints. The
family of structures obtained from the DG calculations was subjected to energy minimization and molecular dynamics simulation
using previously defined force field parameters for the heme and its ligands. In all stages of the calculations, the solution
structure is well defined and similar to the now available X-ray structure.
Received: 18 January 1996 / Accepted: 19 April 1996 相似文献
942.
943.
Nicla Romano Maria Rosaria Baldassini Francesca Renata Terribili Luigi Abelli Lucia Mastrolia Massimo Mazzini 《Polar Biology》1997,18(5):358-362
Lymphomyeloid organs of the Antarctic fish Trematomus bernacchii were studied with the aim of analysing some morphological aspects related to adaptation to low environmental temperature.
The thymus of T. bernacchii was flattened, incompletely lobated and scarcely regionalised. It was filled by lymphoid elements intermingled with stromal
elements. The head kidney appeared highly vascularised and mainly lymphopoietic. The spleen appeared mainly erythropoietic,
with scarcely developed areas of white pulp.
Received: 10 February 1997 / Accepted: 4 May 1997 相似文献
944.
Brown Jillian R.; Guther Maria Lucia S.; Field Robert A.; Ferguson Michael A. J. 《Glycobiology》1997,7(4):549-558
A series of hydrophobic mannosides were synthesized and testedfor their ability to act as acceptor substrates for mannosyltransferasesin a Trypanosoma brucei cell-free system. The thiooctyl -mannosidesand octyl -mannosides all accepted single mannose residues in-linkage, as judged by thin layer chromatography of the productsbefore and after jack bean -mannosidase digestion. The mannosylationreactions were inhibited by amphomycin, suggesting that theimmediate donor was dolicholphosphate-mannose (Dol-P-Man) inall cases. The transferred -mannose residues were shown to beboth 1-2 and 1-6 linked by Aspergillus phoenicis -mannosidaseand acetolysis treatments, respectively. These data suggestthat the compounds can act as acceptor substrates for the Dol-P-Mandependent 1-2 and 1-6 mannosyltransferases of the GPI biosyntheticpathway and/or the dolichol-cycle of protein N-glycosylation.One of the compounds, Man1-6Man1-O-(CH2)7CH3, inhibited endogenousGPI biosynthesis in the cell-free system, suggesting that itcould be a substrate for the trypanosome Dol-P-Man:Man2GlcN-Pl1-2 mannosyltransferase. dolichol glycosylphosphatidylinositol mannosyltransferase trypanosome 相似文献
945.
Massuo J. Kato Lucia M.X. Lopes Hipólito F. Paulino Fo Massayoshi Yoshida Otto R. Gottlieb 《Phytochemistry》1985,24(3):533-536
The fruits of Virola sebifera and V. elongata (Myristicaceae) contain three ω-phenylundecanoyl-substituted compounds, a 2,6-dihydroxybenzene, a 2,6-dihydroxy-4-methoxybenzene and a 3-hydroxycyclohexan-2,6-dione. Three additional 2,6-dihydroxybenzenes are substituted by hexadecanoyl, hexadec-4Z-enoyl and 8-hydroxyoctadec-4Z-enoyl groups. 相似文献
946.
The carbon partitioning of the epipelic diatom Cylindrotheca closterium (Ehrenberg) Reiman and Lewin isolated from the Adriatic Sea was studied in the laboratory under varying scenarios of nutrient limitation. Total number of cells, photosynthesis measured at 695 μmol photons·m − 2 ·s − 1 irradiance (P695- μ mol ), chlorophyll ( a + c ) content, respiration, extracellular polymeric substances (EPS), total particulate carbohydrate (TPC), and dissolved carbohydrate were evaluated under nitrogen and phosphorus deficiencies in culture. The highest total number of cells was found in the control, whereas the nitrogen-limited treatment showed the lowest value. During the transition phase of growth, photosynthesis in the nitrogen-limited treatment was 3-fold lower than in the phosphorus-limited treatment and 4-fold lower than in the control. Differences in respiration rates and chlorophyll ( a + c ) content were even more marked. Dissolved carbohydrate remained the same in all the treatments, whereas during the transition and stationary phase, EPS presented the highest values under phosphorus limitation and the lowest in the control treatment. The production of EPS was closely linked to the periods of carbon assimilation (transition phase) in the nutrient depleted treatments, especially in the phosphorus-limited treatment. These results point out the relevance of the nutrient imbalance (nitrogen or phosphorus) in the production of EPS by the benthic or resuspended diatoms and suggest that these diatoms play an important role in nutrient-unbalanced systems like sediments or marine snow. 相似文献
947.
Influence of caffeine on 3,4‐methylenedioxymethamphetamine‐induced dopaminergic neuron degeneration and neuroinflammation is age‐dependent 下载免费PDF全文
948.
Glycosylation is a co- and post-translational modification that is critical for the regulation of the biophysical properties and biological activities of diverse proteins. Biosynthetic pathways for protein glycosylation are inherently inefficient, resulting in high structural diversity in mature glycoproteins. Macroheterogeneity is the structural diversity due to the presence or absence of glycans at specific glycosylation sites, and is caused by inefficiency in the initial transfer of glycans to proteins. Here, we review the enzymatic and evolutionary mechanisms controlling macroheterogeneity, its biological consequences in physiological and disease states, its relevance to heterologous production and glycoengineering of glycoproteins, and mass spectrometry based methods for its analysis. We highlight the importance of the analysis of macroheterogeneity for a complete understanding of glycoprotein biosynthesis and function, and emphasize how advances in mass spectrometry glycoproteomics will enable analysis of this critical facet of glycoprotein structural diversity. 相似文献
949.
Lucia Kraková Katarína Šoltys Jaroslav Budiš Tomáš Grivalský František Ďuriš Domenico Pangallo Tomáš Szemes 《Extremophiles : life under extreme conditions》2016,20(5):795-808
Different protocols based on Illumina high-throughput DNA sequencing and denaturing gradient gel electrophoresis (DGGE)-cloning were developed and applied for investigating hot spring related samples. The study was focused on three target genes: archaeal and bacterial 16S rRNA and mcrA of methanogenic microflora. Shorter read lengths of the currently most popular technology of sequencing by Illumina do not allow analysis of the complete 16S rRNA region, or of longer gene fragments, as was the case of Sanger sequencing. Here, we demonstrate that there is no need for special indexed or tailed primer sets dedicated to short variable regions of 16S rRNA since the presented approach allows the analysis of complete bacterial 16S rRNA amplicons (V1–V9) and longer archaeal 16S rRNA and mcrA sequences. Sample augmented with transposon is represented by a set of approximately 300 bp long fragments that can be easily sequenced by Illumina MiSeq. Furthermore, a low proportion of chimeric sequences was observed. DGGE-cloning based strategies were performed combining semi-nested PCR, DGGE and clone library construction. Comparing both investigation methods, a certain degree of complementarity was observed confirming that the DGGE-cloning approach is not obsolete. Novel protocols were created for several types of laboratories, utilizing the traditional DGGE technique or using the most modern Illumina sequencing. 相似文献
950.
Therapeutic Approaches in Mitochondrial Dysfunction,Proteolysis, and Structural Alterations of Diaphragm and Gastrocnemius in Rats With Chronic Heart Failure 下载免费PDF全文