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排序方式: 共有4716条查询结果,搜索用时 203 毫秒
911.
912.
Vincenzo Guida Maria Cantarella Angela Chambery Maria C. Mezzacapo Augusto Parente Nicola Landi Valeria Severino Antimo Di Maro 《Molecular biotechnology》2014,56(8):738-746
Four novel basic peroxidases, named AaP-1, AaP-2, AaP-3, and AaP-4, were purified from Asparagus acutifolius L. seeds by cation-exchange and gel filtration chromatographies. The four proteins showed a similar electrophoretic mobility of 46 kDa while, by MALDI–TOF MS, different Mr values of 42758.3, 41586.9, 42796.3, and 41595.5 were determined for AaP-1, AaP-2, AaP-3, and AaP-4, respectively. N-terminal sequences of AaPs 1–4 up to residue 20 showed a high percentage of identity with the peroxidase from Glycine max. In addition, AaP-1, AaP-2, AaP-3, and AaP-4 were found to be glycoproteins, containing 21.75, 22.27, 25.62, and 18.31 % of carbohydrates, respectively. Peptide mapping and MALDI–TOF MS analysis of AaPs 1–4 showed that the structural differences between AaP-1 and AaP-2 and AaP-3 and AaPs-4 were mainly due to their glycan content. We also demonstrate that AaPs were able to remove phenolic compounds from olive oil mill wastewaters with a higher catalytic efficiency with respect to horseradish peroxidase, thus representing candidate enzymes for potential biotechnological applications in the environmental field. 相似文献
913.
Nicola J. Rutherford Brenda D. Moore Todd E. Golde Benoit I. Giasson 《Journal of neurochemistry》2014,131(6):859-867
The discoveries of mutations in SNCA were seminal findings that resulted in the knowledge that α‐synuclein (αS) is the major component of Parkinson's disease‐associated Lewy bodies. Since the pathologic roles of these protein inclusions and SNCA mutations are not completely established, we characterized the aggregation properties of the recently identified SNCA mutations, H50Q and G51D, to provide novel insights. The properties of recombinant H50Q, G51D, and wild‐type αS to polymerize and aggregate into amyloid were studied using (trans,trans)‐1‐bromo‐2,5‐bis‐(4‐hydroxy)styrylbenzene fluorometry, sedimentation analyses, electron microscopy, and atomic force microscopy. These studies showed that the H50Q mutation increases the rate of αS aggregation, whereas the G51D mutation has the opposite effect. However, H50Q and G51D αS could still be similarly induced to form intracellular aggregates from the exposure to exogenous amyloidogenic seeds under conditions that promote their cellular entry. Both mutant αS proteins, but especially G51D, promoted cellular toxicity under cellular stress conditions. These findings reveal that the novel pathogenic SNCA mutations, H50Q and G51D, have divergent effects on aggregation properties relative to the wild‐type protein, with G51D αS demonstrating reduced aggregation despite presenting with earlier disease onset, suggesting that these mutants promote different mechanisms of αS pathogenesis.
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916.
917.
Okino Luci Kimie Machado Kátia Maria Gomes Fabris Carla Bononi Vera Lúcia Ramos 《World journal of microbiology & biotechnology》2000,16(8-9):889-893
A total of 116 strains of Brazilian tropical rainforest basidiomycetes were evaluated in terms of their ability to oxidize
the dye rhemazol brilliant blue R (RBBR) and guaiacol. Laccase and peroxidase activities were detected by the drop test using
solutions of α-naphthol and pyrogallol, respectively. RBBR and guaiacol oxidation occurred in 96.6 and 87.1% of the strains
tested, respectively. One hundred strains oxidized both substrates. In the drop test, most strains presented laccase (96.6%)
and peroxidase (92.2%) activity. The quick screening method used here can be useful to identify ligninolytic fungal strains
to be used in various biotechnological applications.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
918.
Coaggregation between Aquatic Bacteria Is Mediated by Specific-Growth-Phase-Dependent Lectin-Saccharide Interactions 总被引:4,自引:1,他引:3 下载免费PDF全文
Alex H. Rickard Stephen A. Leach Clive M. Buswell Nicola J. High Pauline S. Handley 《Applied microbiology》2000,66(1):431-434
Coaggregating strains of aquatic bacteria were identified by partial 16S rRNA gene sequencing. The coaggregation abilities of four strains of Blastomonas natatoria and one strain of Micrococcus luteus varied with culture age but were always maximum in the stationary phase of growth. Each member of a coaggregating pair carried either a heat- and protease-sensitive protein (lectin) adhesin or a saccharide receptor, as coaggregation was reversed by sugars. 相似文献
919.
Detection of Astroviruses, Enteroviruses, and Adenovirus Types 40 and 41 in Surface Waters Collected and Evaluated by the Information Collection Rule and an Integrated Cell Culture-Nested PCR Procedure 总被引:5,自引:3,他引:2 下载免费PDF全文
920.
Vronique Roig-Zamboni Sarah Barelier Robert Dixon Nicola F. Galley Amani Ghanem Quoc Phong Nguyen Hloize Cahuzac Bartomiej Salamaga Peter J. Davis Yves Bourne Stphane Mesnage Florence Vincent 《The Journal of biological chemistry》2022,298(5)
The cleavage of septal peptidoglycan at the end of cell division facilitates the separation of the two daughter cells. The hydrolases involved in this process (called autolysins) are potentially lethal enzymes that can cause cell death; their activity, therefore, must be tightly controlled during cell growth. In Enterococcus faecalis, the N-acetylglucosaminidase AtlA plays a predominant role in cell separation. atlA mutants form long cell chains and are significantly less virulent in the zebrafish model of infection. The attenuated virulence of atlA mutants is underpinned by a limited dissemination of bacterial chains in the host organism and a more efficient uptake by phagocytes that clear the infection. AtlA has structural homologs in other important pathogens, such as Listeria monocytogenes and Salmonella typhimurium, and therefore represents an attractive model to design new inhibitors of bacterial pathogenesis. Here, we provide a 1.45 Å crystal structure of the E. faecalis AtlA catalytic domain that reveals a closed conformation of a conserved β-hairpin and a complex network of hydrogen bonds that bring two catalytic residues to the ideal distance for an inverting mechanism. Based on the model of the AtlA–substrate complex, we identify key residues critical for substrate recognition and septum cleavage during bacterial growth. We propose that this work will provide useful information for the rational design of specific inhibitors targeting this enterococcal virulence factor and its orthologs in other pathogens. 相似文献