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941.
B. Bahramnejad P. H. Goodwin J. Zhang C. Atnaseo Larry R. Erickson 《Plant cell reports》2010,29(11):1235-1250
A collection of 29 pathogenesis-related 10 (PR10) genes of Medicago sativa and Medicago truncatula showed that they were almost all obtained from cDNA libraries of tissues undergoing abiotic or biotic stresses. The predicted
proteins could be divided into two subclasses, PR10.1 and PR10.2, but in silico predicted models of their three-dimensional
structures revealed that they could be further divided based on size of the hydrophobic internal cavity and number of β-bulges.
A comparison of the expression of two highly similar M. sativa subclass PR10.1 genes, MsPR10.1A and MsPR10.1B, predicted to have similar sized hydrophobic internal cavities, but a different number of β-bulges revealed differences in
their expression patterns. MsPR10.1A was induced faster than MsPR10.1B by ABA, ethylene, and X. campestris pv. alfalfae, but slower than MsPR10.1B by harvesting and wounding. Unlike MsPR10.1A, MsPR10.1B expression was induced in non-harvested tissues following harvesting, but was not induced by heat treatment. Histochemical
observations of Nicotiana benthamiana transformed with 657 bp of the MsPR10.1A promoter fused to the β-glucuronidase (GUS) gene showed that GUS expression was wound-inducible in leaves, which was consistent
with MsPR10.1A expression in alfalfa leaves. GUS expression in stems and leaves was mostly in vascular tissue. The MsPR10.1A promoter may be valuable in controlling the expression in vascular tissues and disease resistance. 相似文献
942.
Edward T. Olejniczak Qiaoqiao Ruan Robert N. Ziemann Larry G. Birkenmeyer Sylvia C. Saldana Sergey Y. Tetin 《Biopolymers》2010,93(7):657-667
The recent remarkable rise in biomedical applications of antibodies and their recombinant constructs has shifted the interest in determination of antigenic epitopes in target proteins from the areas of protein science and molecular immunology to the vast fields of modern biotechnology. In this article, we demonstrated that measuring binding induced changes in two‐dimensional NMR spectra enables rapid determination of antibody binding footprints on target protein antigens. Such epitopes recognized by six high‐affinity monoclonal murine antibodies (mAbs) against human neutrophil gelatinase‐associated lipocalin (NGAL) were determined by measuring chemical shifts or broadening of peaks in 1H‐15N‐TROSY HSQC and 1H‐13C HSQC spectra of isotope‐labeled NGAL occurring upon its binding to the antibodies. Locations of the epitopes defined by the NMR studies are in good agreement with the results of antibody binding pairing observed by dual‐color fluorescence cross‐correlation spectroscopy. In all six cases, the antibodies recognize conformational epitopes in regions of relatively rigid structure on the protein. None of the antibodies interact with the more flexible funnel‐like opening of the NGAL calyx. All determined epitope areas in NGAL reflect the dimensions of respective antibody binding surface (paratopes) and contain amino acid residues that provide strong interactions. This NMR‐based approach offers comprehensive information on antigenic epitopes and can be applied to numerous protein targets of diagnostic or therapeutic interest. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 657–667, 2010. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com 相似文献
943.
Gertrud U. Radu Hayat Caidi Congrong Miao Ralph A. Tripp Larry J. Anderson Lia M. Haynes 《Journal of virology》2010,84(18):9632-9636
We examined whether prophylactically administered anti-respiratory syncytial virus (anti-RSV) G monoclonal antibody (MAb) would decrease the pulmonary inflammation associated with primary RSV infection and formalin-inactivated RSV (FI-RSV)-enhanced disease in mice. MAb 131-2G administration 1 day prior to primary infection reduced the pulmonary inflammatory response and the level of RSV replication. Further, intact or F(ab′)2 forms of MAb 131-2G administered 1 day prior to infection in FI-RSV-vaccinated mice reduced enhanced inflammation and disease. This study shows that an anti-RSV G protein MAb might provide prophylaxis against both primary infection and FI-RSV-associated enhanced disease. It is possible that antibodies with similar reactivities might prevent enhanced disease and improve the safety of nonlive virus vaccines.Respiratory syncytial virus (RSV) infection in infants and young children causes substantial bronchiolitis and pneumonia (11, 27, 28, 40) resulting in 40,000 to 125,000 hospitalizations in the United States each year (27). RSV is also a prominent cause of respiratory illness in older children; those of any age with compromised cardiac, pulmonary, or immune systems; and the elderly (6, 7, 11, 17, 18, 39). Despite extensive efforts toward vaccine development (3, 5, 8, 20, 30, 38), none is yet available. Currently, only preventive measures are available that focus on infection control to decrease transmission and prophylactic administration of a humanized IgG monoclonal antibody (MAb) directed against the F protein of RSV (palivizumab) that is recommended for high-risk infants and young children (4, 7, 17). To date, no treatment has been highly effective for active RSV infection (17, 21).The first candidate vaccine, a formalin-inactivated RSV (FI-RSV) vaccine developed in the 1960s, not only failed to protect against disease but led to severe RSV-associated lower respiratory tract infection in young vaccine recipients upon subsequent natural infection (8, 16). The experience with FI-RSV has limited nonlive RSV vaccine development for the RSV-naïve infant and young child. Understanding the factors contributing to disease pathogenesis and FI-RSV vaccine-enhanced disease may identify ways to prevent such a response and to help achieve a safe and effective vaccine.The RSV G, or attachment, protein has been implicated in the pathogenesis of disease after primary infection and FI-RSV-enhanced disease (2, 26, 31). The central conserved region of the G protein contains four evolutionarily conserved cysteines in a cysteine noose structure, within which lies a CX3C chemokine motif (9, 29, 34). The G protein CX3C motif is also immunoactive, as suggested by studies with the mouse model that show that G protein CX3C motif interaction with CX3CR1 alters pulmonary inflammation (41), RSV-specific T-cell responses (12), FI-RSV vaccine-enhanced disease, and expression of the neurokinin substance P (14) and also depresses respiratory rates (32). Recent studies demonstrated that therapeutic treatment with a murine anti-RSV G protein monoclonal antibody (MAb 131-2G) which blocks binding to CX3CR1 can reduce pulmonary inflammation associated with primary infection (13, 23). These findings led us to hypothesize that prophylactic administration of this anti-RSV G monoclonal antibody may also diminish pulmonary inflammation associated with RSV infection in naïve and in FI-RSV-vaccinated mice. In this study, we evaluate the impact of prophylactic administration of MAb 131-2G on the pulmonary inflammatory response to primary infection and to RSV challenge following FI-RSV immunization in mice. 相似文献
944.
William A. Overholt Rodrigo Diaz Larry Markle J.C. Medal 《Biocontrol Science and Technology》2010,20(8):791-807
The effect of herbivory by Gratiana boliviana Spaeth (Coleoptera: Chrysomelidae) on the invasive, tropical soda apple (TSA) (Solanum viarum Dunal, Solanaceae), was investigated using exclusion methods and by monitoring the density of G. boliviana and the weed at four locations over a period of 40 months. TSA plants protected by insecticide were taller, wider, and had greater canopy cover that unprotected plants, and plants in closed cages were taller and wider than those in open cages. Survival of plants was higher in plots protected with insecticide than in unprotected plots in both years of a 2-year study. In the population dynamics study, the initial density of TSA was 4–5 times higher at one of the locations than at the other three sites, but within 3 years, TSA density at the high density site had declined by 90%. At the three sites which initially had a low abundance of TSA, density remained low throughout the study. The intrinsic rate of increase of G. boliviana varied between –3.9 and 4.5, but over the 3-year study, was not different from zero, indicating a stable population. The intrinsic rate of increase was lower than zero for the period from October to January, and greater than zero during the January to April period. In the periods from April to July and July to October, the rate of increase was not different from zero. The implications of these results for biological control of TSA in Florida are discussed. 相似文献
945.
Anh P. Truong Gary D. Probst Jose Aquino Larry Fang Louis Brogley Jennifer M. Sealy Roy K. Hom John A. Tucker Varghese John Jay S. Tung Michael A. Pleiss Andrei W. Konradi Hing L. Sham Michael S. Dappen Gergley Tóth Nanhua Yao Eric Brecht Hu Pan Dean R. Artis Lany Ruslim John-Michael Sauer 《Bioorganic & medicinal chemistry letters》2010,20(16):4789-4794
Herein we describe further evolution of hydroxyethylamine inhibitors of BACE-1 with enhanced permeability characteristics necessary for CNS penetration. Variation at the P2′ position of the inhibitor with more polar substituents led to compounds 19 and 32, which retained the potency of more lipophilic analog 1 but with much higher observed passive permeability in MDCK cellular assay. 相似文献
946.
Larry R. McLean Ying Zhang Hua Li Yong-Mi Choi Zuoning Han Roy J. Vaz Yi Li 《Bioorganic & medicinal chemistry letters》2010,20(6):1821-1824
In the course of a fragment screening campaign by in silico docking followed by X-ray crystallography, a novel binding site for migration inhibitory factor (MIF) inhibitors was demonstrated. The site is formed by rotation of the side-chain of Tyr-36 to reveal a surface binding site in MIF that is hydrophobic and surrounded by aromatic side-chain residues. The crystal structures of two small inhibitors that bind to this site and of a quinolinone inhibitor, that spans the canonical deep pocket near Pro-1 and the new surface binding site, have been solved. These results suggest new opportunities for structure-based design of MIF inhibitors. 相似文献
947.
Kang DW Kim YS Lim KS Kim MS Pearce LV Pavlyukovets VA Tao AK Lang-Kuhs KA Blumberg PM Lee J 《Bioorganic & medicinal chemistry》2010,18(22):8092-8105
As an extension of our analysis of the effect of halogenation on thiourea TRPV1 agonists, we have now modified selected 4-hydroxy(or 4-amino)-3-methoxyphenyl acetamide TRPV1 agonists by 5- or 6-halogenation on the aromatic A-region and evaluated them for potency for TRPV1 binding and regulation and for their pattern of agonism/antagonism (efficacy). Halogenation shifted the functional activity at TRPV1 toward antagonism with a greater extent of antagonism as the size of the halogen increased (I>Br>Cl), as previously observed for the thiourea series. The extent of antagonism was greater for halogenation at the 5-position than at the 6-position, in contrast to SAR for the thiourea series. In this series, compounds 55 and 75 showed the most potent antagonism, with K(i) (ant)=2.77 and 2.19nM, respectively, on rTRPV1 expressed in Chinese hamster ovary cells. The compounds were thus ca. 40-60-fold more potent than 6'-iodononivamide. 相似文献
948.
949.
Troponin is a pivotal regulatory protein that binds Ca(2+) reversibly to act as the muscle contraction on-off switch. To understand troponin function, the dynamic behavior of the Ca(2+)-saturated cardiac troponin core domain was mapped in detail at 10 °C, using H/D exchange-mass spectrometry. The low temperature conditions of the present study greatly enhanced the dynamic map compared with previous work. Approximately 70% of assessable peptide bond hydrogens were protected from exchange sufficiently for dynamic measurement. This allowed the first characterization by this method of many regions of regulatory importance. Most of the TnI COOH terminus was protected from H/D exchange, implying an intrinsically folded structure. This region is critical to the troponin inhibitory function and has been implicated in thin filament activation. Other new findings include unprotected behavior, suggesting high mobility, for the residues linking the two domains of TnC, as well as for the inhibitory peptide residues preceding the TnI switch helix. These data indicate that, in solution, the regulatory subdomain of cardiac troponin is mobile relative to the remainder of troponin. Relatively dynamic properties were observed for the interacting TnI switch helix and TnC NH(2)-domain, contrasting with stable, highly protected properties for the interacting TnI helix 1 and TnC COOH-domain. Overall, exchange protection via protein folding was relatively weak or for a majority of peptide bond hydrogens. Several regions of TnT and TnI were unfolded even at low temperature, suggesting intrinsic disorder. Finally, change in temperature prominently altered local folding stability, suggesting that troponin is an unusually mobile protein under physiological conditions. 相似文献
950.
Mousheng Wu Hoa Dinh Le Meitian Wang Vladimir Yurkov Alexander Omelchenko Mark Hnatowich Jay Nix Larry V. Hryshko Lei Zheng 《The Journal of biological chemistry》2010,285(4):2554-2561
Na+/Ca2+ exchangers (NCX) constitute a major Ca2+ export system that facilitates the re-establishment of cytosolic Ca2+ levels in many tissues. Ca2+ interactions at its Ca2+ binding domains (CBD1 and CBD2) are essential for the allosteric regulation of Na+/Ca2+ exchange activity. The structure of the Ca2+-bound form of CBD1, the primary Ca2+ sensor from canine NCX1, but not the Ca2+-free form, has been reported, although the molecular mechanism of Ca2+ regulation remains unclear. Here, we report crystal structures for three distinct Ca2+ binding states of CBD1 from CALX, a Na+/Ca2+ exchanger found in Drosophila sensory neurons. The fully Ca2+-bound CALX-CBD1 structure shows that four Ca2+ atoms bind at identical Ca2+ binding sites as those found in NCX1 and that the partial Ca2+ occupancy and apoform structures exhibit progressive conformational transitions, indicating incremental regulation of CALX exchange by successive Ca2+ binding at CBD1. The structures also predict that the primary Ca2+ pair plays the main role in triggering functional conformational changes. Confirming this prediction, mutagenesis of Glu455, which coordinates the primary Ca2+ pair, produces dramatic reductions of the regulatory Ca2+ affinity for exchange current, whereas mutagenesis of Glu520, which coordinates the secondary Ca2+ pair, has much smaller effects. Furthermore, our structures indicate that Ca2+ binding only enhances the stability of the Ca2+ binding site of CBD1 near the hinge region while the overall structure of CBD1 remains largely unaffected, implying that the Ca2+ regulatory function of CBD1, and possibly that for the entire NCX family, is mediated through domain interactions between CBD1 and the adjacent CBD2 at this hinge. 相似文献