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111.
Synthetic peptides mimicking the binding site of human acetylcholinesterase for its inhibitor fasciculin 2 下载免费PDF全文
Uwe Kafurke Ariel Erijman Yonatan Aizner Julia M. Shifman Jutta Eichler 《Journal of peptide science》2015,21(9):723-730
Molecules capable of mimicking protein binding and/or functional sites present useful tools for a range of biomedical applications, including the inhibition of protein–ligand interactions. Such mimics of protein binding sites can currently be generated through structure‐based design and chemical synthesis. Computational protein design could be further used to optimize protein binding site mimetics through rationally designed mutations that improve intermolecular interactions or peptide stability. Here, as a model for the study, we chose an interaction between human acetylcholinesterase (hAChE) and its inhibitor fasciculin‐2 (Fas) because the structure and function of this complex is well understood. Structure‐based design of mimics of the hAChE binding site for Fas yielded a peptide that binds to Fas at micromolar concentrations. Replacement of hAChE residues known to be essential for its interaction with Fas with alanine, in this peptide, resulted in almost complete loss of binding to Fas. Computational optimization of the hAChE mimetic peptide yielded a variant with slightly improved affinity to Fas, indicating that more rounds of computational optimization will be required to obtain peptide variants with greatly improved affinity for Fas. CD spectra in the absence and presence of Fas point to conformational changes in the peptide upon binding to Fas. Furthermore, binding of the optimized hAChE mimetic peptide to Fas could be inhibited by hAChE, providing evidence for a hAChE‐specific peptide–Fas interaction. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
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Thomas E Edwards Ariel B Abramov Eric R Smith Ruth O Baydo Jess T Leonard David J Leibly Kaitlin B Thompkins Matthew C Clifton Anna S Gardberg Bart L Staker Wesley C Van Voorhis Peter J Myler Lance J Stewart 《BMC structural biology》2011,11(1):1-9
Background
F-spondin is a multi-domain extracellular matrix (ECM) protein and a contact-repellent molecule that directs axon outgrowth and cell migration during development. The reelin_N domain and the F-spondin domain (FS domain) comprise a proteolytic fragment that interacts with the cell membrane and guides the projection of commissural axons to floor plate. The FS domain is found in F-spondins, mindins, M-spondin and amphiF-spondin.Results
We present the crystal structure of human F-spondin FS domain at 1.95Å resolution. The structure reveals a Ca2+-binding C2 domain variant with an 8-stranded antiparallel β-sandwich fold. Though the primary sequences of the FS domains of F-spondin and mindin are less than 36% identical, their overall structures are very similar. The unique feature of F-spondin FS domain is the presence of three disulfide bonds associated with the N- and C-termini of the domain and a highly conserved N-linked glycosylation site. The integrin-binding motif found in mindin is not conserved in the F-spondin FS domain.Conclusion
The structure of the F-spondin FS domain completes the structural studies of the multiple-domain ECM molecule. The homology of its core structure to a common Ca2+- and lipid-binding C2 domain suggests that the F-spondin FS domain may be responsible for part of the membrane targeting of F-spondin in its regulation of axon development. The structural properties of the FS domain revealed in this study pave the way for further exploration into the functions of F-spondin. 相似文献114.
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Sonja C. Vernes Peter L. Oliver Elizabeth Spiteri Helen E. Lockstone Rathi Puliyadi Jennifer M. Taylor Joses Ho Cedric Mombereau Ariel Brewer Ernesto Lowy Jér?me Nicod Matthias Groszer Dilair Baban Natasha Sahgal Jean-Baptiste Cazier Jiannis Ragoussis Kay E. Davies Daniel H. Geschwind Simon E. Fisher 《PLoS genetics》2011,7(7)
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Molecular cloning of IGF-1 and IGF-1 receptor and their expression pattern in the Chilean flounder (Paralichthys adspersus) 总被引:1,自引:0,他引:1
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Some groups of fish, such as those belonging to the Order Tetraodontiformes, may differ significantly in the amount and location of heterochromatin in the chromosomes. There is a marked variation in DNA content of more than seven-fold among the families of this Order. However, the karyoevolutionary mechanisms responsible for this variation are essentially unknown. The largest genomic contents are present in species of the family Ostraciidae (2.20–2.60 pg). The present study cytogenetically characterized two species of the family Ostraciidae, Acanthostracion polygonius and A. quadricornis, using conventional staining, C-bandings, Ag-NOR, CMA3/DAPI, AluI, PstI, EcoRI, TaqI and HinfI restriction enzymes (REs) and double FISH with 18S and 5S rDNA probes. The karyotypes of both species showed 2n = 52 acrocentric chromosomes (FN = 52; chromosome arms) and pronounced conserved structural characteristics. A significant heterochromatic content was observed equilocally distributed in pericentromeric position in all the chromosome pairs. This condition is unusual in relation to the karyotypes of other families of Tetraodontiformes and probability is the cause of the higher DNA content in Ostraciidae. Given the role played by repetitive sequences in the genomic reorganization of this Order, it is suggested that the conspicuous heterochromatic blocks, present in the same chromosomal position and with apparently similar composition, may have arisen or undergo evolutionary changes in concert providing clues about the chromosomal mechanisms which led to extensive variation in genomic content of different Tetraodontiformes families. 相似文献
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Sicuri E Bardají A Sigauque B Maixenchs M Nhacolo A Nhalungo D Macete E Alonso PL Menéndez C 《PloS one》2011,6(12):e28744