排序方式: 共有63条查询结果,搜索用时 31 毫秒
41.
Klammt C Maslennikov I Bayrhuber M Eichmann C Vajpai N Chiu EJ Blain KY Esquivies L Kwon JH Balana B Pieper U Sali A Slesinger PA Kwiatkowski W Riek R Choe S 《Nature methods》2012,9(8):834-839
Although nearly half of today's major pharmaceutical drugs target human integral membrane proteins (hIMPs), only 30 hIMP structures are currently available in the Protein Data Bank, largely owing to inefficiencies in protein production. Here we describe a strategy for the rapid structure determination of hIMPs, using solution NMR spectroscopy with systematically labeled proteins produced via cell-free expression. We report new backbone structures of six hIMPs, solved in only 18 months from 15 initial targets. Application of our protocols to an additional 135 hIMPs with molecular weight <30 kDa yielded 38 hIMPs suitable for structural characterization by solution NMR spectroscopy without additional optimization. 相似文献
42.
Eletskiĭ AV Maslennikov IV Kukhtina VV Utkin IuN Tsetlin VI Arsen'ev AS 《Bioorganicheskaia khimiia》2001,27(2):89-101
Resonances in the two-dimensional 1H NMR spectra of a weak toxin (WTX) from the venom of cobra Naja kaouthia for all 65 amino acid residues were assigned. The amino acid sequence of WTX, determined by the sequentional assignment of spin systems, was found to be similar to that of the CM-9a toxin from the N. kaouthia venom. Unlike CM-9a, WTX contains an additional Trp36 residue; Lys50 and Tyr52 are interchanged; and there is a Thr residue in place of Arg2. For some residues of WTX, the presence of two components of approximately equal intensities in the spectra was shown, which is explained by the conformational heterogeneity of the polypeptide owing to the cis-trans isomerization of the peptide bond Arg32-Pro33. The data (contacts of the nuclear Overhauser effect, constants of spin-spin coupling of protons, and rates of exchange of amide protons by deuterium of the solvent) made it possible to determine the secondary structure of two forms of WTX, which is characterized by the presence of two antiparallel beta-sheets, one of which consists of two strands (regions 1-5 and 13-17) and the other, of three strands (regions 23-28, 38-43, and 55-59). 相似文献
43.
Shevchenko O. G. Orlova T. Yu. Maslennikov S. I. 《Russian Journal of Marine Biology》2004,30(1):11-19
The qualitative and quantitative composition of the Chaetoceros Ehr. species was studied in Amursky Bay (Sea of Japan) from January 1996 until May 1998. In all, 30 species, 1 variety, and 1 form of this genus were registered. The species Chaetoceros occurred in plankton throughout the year at a water temperature of –1.8–25°C and a salinity of 11–35. The numbers of Chaetoceros species varied between 100 and 1071000 cells/l, and the biomass varied between 0.9 × 10–3 and 3.3 g/m3. The numbers were maximum in summer and minimum in the beginning of spring. The Chaetoceros species comprised 45–70 and 5–18% (winter), 68–98 and 65–95% (spring), 50% (summer), and 20% (autumn) of the total phytoplankton numbers and biomass. Six dominant species and 1 variety of Chaetoceros were found. Seasonal complexes formed by the Chaetoceros species were identified and described. 相似文献
44.
Bocharov EV Pustovalova YE Pavlov KV Volynsky PE Goncharuk MV Ermolyuk YS Karpunin DV Schulga AA Kirpichnikov MP Efremov RG Maslennikov IV Arseniev AS 《The Journal of biological chemistry》2007,282(22):16256-16266
BNip3 is a prominent representative of apoptotic Bcl-2 proteins with rather unique properties initiating an atypical programmed cell death pathway resembling both necrosis and apoptosis. Many Bcl-2 family proteins modulate the permeability state of the outer mitochondrial membrane by forming homo- and hetero-oligomers. The structure and dynamics of the homodimeric transmembrane domain of BNip3 were investigated with the aid of solution NMR in lipid bicelles and molecular dynamics energy relaxation in an explicit lipid bilayer. The right-handed parallel helix-helix structure of the domain with a hydrogen bond-rich His-Ser node in the middle of the membrane, accessibility of the node for water, and continuous hydrophilic track across the membrane suggest that the domain can provide an ion-conducting pathway through the membrane. Incorporation of the BNip3 transmembrane domain into an artificial lipid bilayer resulted in pH-dependent conductivity increase. A possible biological implication of the findings in relation to triggering necrosis-like cell death by BNip3 is discussed. 相似文献
45.
Darul Romane Gavashelishvili Alexander Saveljev Alexander P. Seryodkin Ivan V. Linnell John D. C. Okarma Henryk Bagrade Guna Ornicans Aivars Ozolins Janis Männil Peep Khorozyan Igor Melovski Dime Stojanov Aleksandar Trajçe Aleksandër Hoxha Bledi Dvornikov Mikhail G. Galsandorj Naranbaatar Okhlopkov Innokentiy Mamuchadze Jimsher Yarovenko Yuriy A. Akkiev Muzigit I. Sulamanidze Giorgi Kochiashvili Vazha Şahin Mehmet Kürşat Trepet Sergey A. Pkhitikov Alim B. Farhadinia Mohammad S. Godoy Jose A. Jászay Tomáš Ratkiewicz Mirosław Schmidt Krzysztof 《Journal of Mammalian Evolution》2022,29(1):51-62
Journal of Mammalian Evolution - We studied the relationship between the variability and contemporary distribution of pelage phenotypes in one of most widely distributed felid species and an array... 相似文献
46.
G. I. Dolgachev D. D. Maslennikov A. G. Ushakov A. S. Fedotkin I. A. Khodeev 《Plasma Physics Reports》2007,33(10):830-838
One of the key problems of the Baikal project, intended to create a superpower pulsed generator for ICF experiments, is that of matching a multimodule plasma opening switch (POS) to a liner load. An intermediate inductance or a separating discharger is proposed to be used as a matching element between the POS and the load. An analysis is made of the effect of both versions of the matching system on the synchronization of the POS modules and the energy transfer from the inductive storage to the load. Methods for optimizing the matching element are examined. It is shown that the POS modules can be synchronized and the inductive storage energy can be efficiently transferred to a low-impedance load. A multigap vacuum discharger with a point anode and plane cathode is to be used as a separating discharger. Such an electrode system make it possible to concentrate the electric field at the point anode and to substantially enhance the electric strength of the inter-electrode gap. Results are presented from experimental studies of vacuum breakdown in such an electrode system with a gap length of about 1 mm. 相似文献
47.
48.
Yu. A. Zolotarev E. V. Bocharov A. K. Dadayan I. E. Kasheverov M. N. Zhmak I. V. Maslennikov Yu. A. Borisov A. S. Arseniev N. F. Myasoedov V. I. Tsetlin 《Russian Journal of Bioorganic Chemistry》2000,26(9):527-531
Tritium-labeled α-conotoxin G1 with a molar radioactivity of 35 Ci/mmol and full biological activity (according to the binding
to nicotinic acetylcholine receptor) was obtained by the high-temperature solid-state catalytic isotope exchange (HSCIE).
The tritium distribution in the molecule of α-conotoxin G1 was revealed by3H NMR spectroscopy. Tritium was found in all amino acid residues except for the Asn4-Pro5-Ala6 fragment. The data on the comparative
reactivity of C-H bonds, theab initio quantum-chemical calculation of the hydrogen exchange reaction, and the information on the spatial structures of α-conotoxin
G1 in solution and in crystal state allowed us to establish that the reactivity of H atoms may be increased by their interaction
with the electron donor O and N atoms at the transition state of the HSCIE reaction. A decrease in the rate of the HSCIE reaction
could be caused by both a poor spatial accessibility of C-H bonds and a limited mobility of the peptide fragment containing
these bonds. 相似文献
49.
The RCK-containing MthK channel undergoes two inactivation processes: activation-coupled desensitization and acid-induced inactivation. The acid inactivation is mediated by the C-terminal RCK domain assembly. Here, we report that the desensitization gating is governed by a desensitization domain (DD) of the cytoplasmic N-terminal 17 residues. Deletion of DD completely removes the desensitization, and the process can be fully restored by a synthetic DD peptide added in trans. Mutagenesis analyses reveal a sequence-specific determinant for desensitization within the initial hydrophobic segment of DD. Proton nuclear magnetic resonance (1H NMR) spectroscopy analyses with synthetic peptides and isolated RCK show interactions between the two terminal domains. Additionally, we show that deletion of DD does not affect the acid-induced inactivation, indicating that the two inactivation processes are mutually independent. Our results demonstrate that the short N-terminal DD of MthK functions as a complete moveable module responsible for the desensitization. Its interaction with the C-terminal RCK domain may play a role in the gating process. 相似文献
50.
New binding site on common molecular scaffold provides HERG channel specificity of scorpion toxin BeKm-1 总被引:1,自引:0,他引:1
Korolkova YV Bocharov EV Angelo K Maslennikov IV Grinenko OV Lipkin AV Nosyreva ED Pluzhnikov KA Olesen SP Arseniev AS Grishin EV 《The Journal of biological chemistry》2002,277(45):43104-43109
The scorpion toxin BeKm-1 is unique among a variety of known short scorpion toxins affecting potassium channels in its selective action on ether-a-go-go-related gene (ERG)-type channels. BeKm-1 shares the common molecular scaffold with other short scorpion toxins. The toxin spatial structure resolved by NMR consists of a short alpha-helix and a triple-stranded antiparallel beta-sheet. By toxin mutagenesis study we identified the residues that are important for the binding of BeKm-1 to the human ERG K+ (HERG) channel. The most critical residues (Tyr-11, Lys-18, Arg-20, Lys-23) are located in the alpha-helix and following loop whereas the "traditional" functional site of other short scorpion toxins is formed by residues from the beta-sheet. Thus the unique location of the binding site of BeKm-1 provides its specificity toward the HERG channel. 相似文献