N-linked glycosylation in Campylobacter jejuni and its functional transfer into E. coli     

Wacker M  Linton D  Hitchen PG  Nita-Lazar M  Haslam SM  North SJ  Panico M  Morris HR  Dell A  Wren BW  Aebi M 《Science (New York, N.Y.)》2002,298(5599):1790-1793

N-linked protein glycosylation is the most abundant posttranslation modification of secretory proteins in eukaryotes. A wide range of functions are attributed to glycan structures covalently linked to asparagine residues within the asparagine-X-serine/threonine consensus sequence (Asn-Xaa-Ser/Thr). We found an N-linked glycosylation system in the bacterium Campylobacter jejuni and demonstrate that a functional N-linked glycosylation pathway could be transferred into Escherichia coli. Although the bacterial N-glycan differs structurally from its eukaryotic counterparts, the cloning of a universal N-linked glycosylation cassette in E. coli opens up the possibility of engineering permutations of recombinant glycan structures for research and industrial applications.  相似文献   

Activating mutations of NOTCH1 in human T cell acute lymphoblastic leukemia   总被引：1，自引：0，他引：1  

Weng AP  Ferrando AA  Lee W  Morris JP  Silverman LB  Sanchez-Irizarry C  Blacklow SC  Look AT  Aster JC 《Science (New York, N.Y.)》2004,306(5694):269-271

Very rare cases of human T cell acute lymphoblastic leukemia (T-ALL) harbor chromosomal translocations that involve NOTCH1, a gene encoding a transmembrane receptor that regulates normal T cell development. Here, we report that more than 50% of human T-ALLs, including tumors from all major molecular oncogenic subtypes, have activating mutations that involve the extracellular heterodimerization domain and/or the C-terminal PEST domain of NOTCH1. These findings greatly expand the role of activated NOTCH1 in the molecular pathogenesis of human T-ALL and provide a strong rationale for targeted therapies that interfere with NOTCH signaling.  相似文献   

SOCIETIES AND ACADEMIES     

Morris EL 《Science (New York, N.Y.)》1905,22(573):832-834

  相似文献   

Mineralogy at Gusev Crater from the Mössbauer spectrometer on the Spirit Rover     

Morris RV  Klingelhöfer G  Bernhardt B  Schröder C  Rodionov DS  De Souza PA  Yen A  Gellert R  Evlanov EN  Foh J  Kankeleit E  Gütlich P  Ming DW  Renz F  Wdowiak T  Squyres SW  Arvidson RE 《Science (New York, N.Y.)》2004,305(5685):833-836

M?ssbauer spectra measured on Mars by the Spirit rover during the primary mission are characterized by two ferrous iron doublets (olivine and probably pyroxene) and a ferric iron doublet (tentatively associated to nanophase ferric iron oxide). Two sextets resulting from nonstoichiometric magnetite are also present, except for a coating on the rock Mazatzal, where a hematite-like sextet is present. Greater proportions of ferric-bearing phases are associated with undisturbed soils and rock surfaces as compared to fresh rock surfaces exposed by grinding. The ubiquitous presence of olivine in soil suggests that physical rather than chemical weathering processes currently dominate at Gusev crater.  相似文献   

Signal transduction. Sweet conundrum     

Birnbaum MJ 《Science (New York, N.Y.)》2008,319(5868):1348-1349

  相似文献   

Silica sol as a nanoglue: flexible synthesis of composite aerogels     

Morris CA  Anderson ML  Stroud RM  Merzbacher CI  Rolison DR 《Science (New York, N.Y.)》1999,284(5414):622-624

Low-density nanoscale mesoporous composites may be readily synthesized by adding a colloidal or dispersed solid to an about-to-gel silica sol. The silica sol can "glue" a range of chemically and physically diverse particles into the three-dimensional silica network formed upon gelation. If the composite gel is supercritically dried so as to maintain the high porosity of the wet gel, a composite aerogel is formed in which the nanoscopic surface and bulk properties of each component are retained in the solid composite. The volume fraction of the second solid can be varied above or below a percolation threshold to tune the transport properties of the composite aerogel and thereby design nanoscale materials for chemical, electronic, and optical applications.  相似文献   

Memory consolidation and NMDA receptors: discrepancy between genetic and pharmacological approaches     

Day M  Morris RG 《Science (New York, N.Y.)》2001,293(5531):755

  相似文献   

Genome size in conodonts (chordata): inferred variations during 270 million years     

Morris SC  Harper E 《Science (New York, N.Y.)》1988,241(4870):1230-1232

DNA is too unstable to be preserved during fossilization, but it still seems possible to infer the genome content of fossils because in every group of organisms investigated cell size is proportional to quantity of DNA. Accordingly, information on macroevolutionary trends in genome size through millions of years is potentially available. This survey of inferred variation in genome content in fossils is based on measurements of epithelial cells in extinct conodonts over a period of 270 million years. Why genome size varies so widely amongst living organisms is a subject of continuing debate. Paleontology offers a distinct temporal perspective, but lack of data on conodont paleoecology make the proposed adaptive explanations for genome variation difficult to test.  相似文献   

Quantitative Determination of Carbohydrates With Dreywood's Anthrone Reagent     

Morris DL 《Science (New York, N.Y.)》1948,107(2775):254-255

  相似文献   

Genes, genetics, and epigenetics: a correspondence   总被引：2，自引：0，他引：2  

Wu Ct  Morris JR 《Science (New York, N.Y.)》2001,293(5532):1103-1105

Over the past months, as this special issue took shape, the Editors of Science have monitored an exchange of seven letters initiated by three queries from M. Bacon. These queries concern the popular definitions of "genes," "genetics," and "epigenetics." Below, we reprint excerpts from these letters, referring interested readers to www.sciencemag.org/cgi/content/full/293/5532/1103/DC1 for the complete text and additional references.  相似文献