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51.
Villaverde A Feliu JX Arís A Harbottle RP Benito A Coutelle C 《Biotechnology and bioengineering》1998,59(3):294-301
The G-H loop of foot-and-mouth disease virus is a disordered protrusion of the VP1 protein exposed on the virion surface. This short stretch includes an arginine-glycine-aspartic acid tripeptide, a recognized integrin-binding motif, which is responsible for cell attachment and infection. Eight copies of a peptide reproducing the amino acid sequence of this FMDV ligand have been displayed in solvent-exposed regions on an enzymatically active recombinant beta-galactosidase. This viral peptide segment enables the chimeric enzyme to bind mammalian cell lines with different efficiencies, probably depending on the number of suitable cell receptors present on each of them. Moreover, it also promotes the internalization of the attached enzyme, which is transiently active inside the cells. These results suggest further exploration of the potential use of short adhesion peptides of viral origin as cell attachment tags to direct the targeted delivery of both genes and enzymes, instead of whole, infectious viruses. 相似文献
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MA Abo-El Seoud MM Sarhan AE Omar MM Helal 《Archives Of Phytopathology And Plant Protection》2013,46(3):175-184
Essential oils of fennel, peppermint, caraway, eucalyptus, geranium and lemon were tested for their antimicrobial activities against some plant pathogenic micro-organisms (Fusarium oxysporum, Alternaria alternate, Penicilium italicum Penicilium digitatum and Botyritus cinerea). Essential oils of fennel, peppermint, caraway were selected as an active ingredient for the formulation of biocides due to their efficiency in controlling the tested micro-organisms. Successful emulsifiable concentrates (biocides) were prepared from these oils using different emulsifiers (Emulgator B.L.M. Tween20 and Tween80) and different fixed oils (sesame, olive, cotton and soybean oils). Physico-chemical properties of the formulated biocide (spontaneous emulsification, emulsion stability test, cold stability and heat stability tests as well as viscosity, surface tension and pH) were measured. The prepared biocides were ready to be tested for application in a future work as a safe pesticide against different pathogens. 相似文献
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56.
Shiqi Zhang Holger A. Lindner Sarah Kabtni Jaap van den Born Stephan Bakker Gerjan Navis Bernard Kr?mer Benito Yard Sibylle Hauske 《PloS one》2016,11(1)
Background and Aims
The proportion of serum carnosinase (CN-1) recognized by RYSK173 monoclonal antibody negatively correlates with CN-1 activity. We thus hypothesized that the epitope recognized by RYSK173 is accessible only in a catalytically incompetent conformation of the zinc dependent enzyme and we mapped its position in the CN-1 structure. Since patients with kidney failure are often deficient in zinc and other trace elements we also assessed the RYSK173 CN-1 proportion in serum of these patients and studied the influence of hemodialysis hereon in relation to Zn2+ and Cu2+ concentration during hemodialysis.Methods and Results
Epitope mapping using myc-tagged CN-1 fragments and overlapping peptides revealed that the RYSK173 epitope directly contributes to the formation of the dinuclear Zn center in the catalytic domain of homodimeric CN-1. Binding of RYSK173 to CN-1 was however not influenced by addition of Zn2+ or Cu2+ to serum. In serum of healthy controls the proportion of CN-1 recognized by RYSK173 was significantly lower compared to end-stage renal disease (ESRD) patients (1.12 ± 0.17 vs. 1.56 ± 0.40% of total CN-1; p<0.001). During hemodialysis the relative proportion of RYSK173 CN-1 decreased in parallel with increased serum Zn2+ and Cu2+ concentrations after dialysis.Conclusions
Our study clearly indicates that RYSK173 recognizes a sequence within the transition metal binding site of CN-1, thus supporting our hypothesis that metal binding to CN-1 masks the epitope. The CN-1 RYSK173 proportion appears overall increased in ESRD patients, yet it decreases during hemodialysis possibly as a consequence of a relative increase in transition metal bound enzyme. 相似文献57.
Citores Luca; de Benito Fernando M.; Iglesias Rosario; Ferreras J. Miguel; Jimnez Pilar; Argeso Pablo; Farias Gustavo; Mndez Enrique; Girbs Toms 《Journal of experimental botany》1996,47(10):1577-1585
Sambucus (Caprifoliaceae) species contain nigrin b and ebulinI, which are two-chain ribosomeinactivating proteins (RIPs)belonging to a new type of RIPS which are non-toxic to miceand cultured human cells. In this work the presence in fruitsof elder (S. nigra L.) of a new non-toxic type 2 RIP (nigrinf) that co-exists with a lectin known as SNA IV is described.Nigrin f strongly inhibited protein synthesis in mammalian,but not in plant, ribosomes, promoting the depurination of sensitiveribosomes and thus allowing the release of the RIP diagnosticRNA fragment. Nigrin f is composed of two dissimilar subunitslinked by disulphide bridges with apparent Mr values of 31 600and 26 300. The N-terminal amino acid sequence revealed closehomology of the catalytic A chain with type 1 RIPs, especiallythose from Cucurbitaceae, and the B chain with several lectinspreviously isolated from Sambucus species. Nigrin f was nottoxic to mice when injected intraperitoneally up to 2 mg kg1.In addition, NHC human cells were also insensitive to nigrinf up to 60 µg ml1. Anti-nigrin b rabbit polyclonalantibodies reacted with nigrin f, indicating that nigrin b andnigrin f are proteins with similar structures. Key words: Sambucus nigra, elder fruits, nigrin f, ribosomeinactivating protein, characterization 相似文献
58.
Characterization of the novel antifungal chitosanase PgChP and the encoding gene from Penicillium chrysogenum 总被引:1,自引:0,他引:1
Andrea Rodríguez-Martín Raquel Acosta Susan Liddell Félix Núñez María José Benito Miguel A. Asensio 《Applied microbiology and biotechnology》2010,88(2):519-528
The protein PgChP is a new chitosanase produced by Penicillium chrysogenum AS51D that showed antifungal activity against toxigenic molds. Two isoforms were found by SDS-PAGE in the purified extract
of PgChP. After enzymatic deglycosylation, only the smaller isoform was observed by SDS-PAGE. Identical amino acid sequences
were obtained from the two isoforms. Analysis of the molecular mass by electrospray ionization-mass spectrometry revealed
six major peaks from 30 to 31 kDa that are related to different levels of glycosylation. The pgchp gene has 1,146 bp including four introns and an open reading frame encoding a protein of 304 amino acids. The translated
open reading frame has a predicted mass of 32 kDa, with the first 21 amino acids comprising a signal peptide. Two N glycosylation
consensus sequences are present in the protein sequence. The deduced sequence showed high identity with fungal chitosanases.
A high level of catalytic activity on chitosan was observed. PgChP is the first chitosanase described from P. chrysogenum. Given that enzymes produced by this mold species are granted generally recognized as safe status, PgChP could be used as
a food preservative against toxigenic molds and to obtain chitosan oligomers for food additives and nutraceuticals. 相似文献
59.
Matthew G. Stanton Jed Hubbs David Sloman Christopher Hamblett Paula Andrade Minilik Angagaw Grace Bi Regina M. Black Jamie Crispino Jonathan C. Cruz Eric Fan Georgia Farris Bethany L. Hughes Candia M. Kenific Richard E. Middleton George Nikov Peter Sajonz Sanjiv Shah Nirah Shomer Alexander A. Szewczak Benito Munoz 《Bioorganic & medicinal chemistry letters》2010,20(2):755-758
We report herein a novel series of difluoropiperidine acetic acids as modulators of γ-secretase. Synthesis of 2-aryl-3,3-difluoropiperidine analogs was facilitated by a unique and selective β-difluorination with Selectfluor®. Compounds 1f and 2c were selected for in vivo assessment and demonstrated selective lowering of Aβ42 in a genetically engineered mouse model of APP processing. Moreover, in a 7-day safety study, rats treated orally with compound 1f (250 mg/kg per day, AUC0–24 = 2100 μM h) did not exhibit Notch-related effects. 相似文献
60.
O. Dauwalder A. -M. Freydière H. Meugnier Y. Benito M. Chomarat C. Ginevra P. Girardo M. -E. Reverdy J. Etienne G. Lina F. Vandenesch 《Bio Tribune Magazine》2010,36(1):6-11
Concomitant chemoradiotherapy can constitute an alternative to surgical approach in selected patients with bladder carcinoma. TNM staging, histological grading, renal and performance status represent the main prognostic factors useful to define the therapeutic strategy. Biological and genetic factors are still controversial in medical practice. The activation of oncogenes seems to characterize the initiation of superficial lowgrade tumors and the mutations in the tumor suppressor genes (TEN, TP53 and RB) appear as the most important biological features in the in situ and invasive tumors. The expression of p53, Rb, Bcl-2 has an obvious prognostic role but the published studies on molecular factors predictive of radiosensibility are heterogeneous. 相似文献