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71.
Vincenzo Amico Giovanni Nicolosi Giovanna Oriente Mario Piattelli Corrado Tringali 《Phytochemistry》1982,21(3):739-741
A novel acylphloroglucinol, (5Z,8Z11Z,13E,17Z)-2′-eicosa-15(S)-hydroxy-5,8,11,13,17-pentaenoylphloroglucinol, has been isolated from the brown alga Zonaria tournefortii and its structure proved by spectroscopic and chemical methods. 相似文献
72.
Vincenzo Amico Giovanna Oriente Mario Piattelli Giuseppe Ruberto Corrado Tringali 《Phytochemistry》1982,21(2):421-424
2′E,6′E)-2-(10′,11′-Dihydroxygeranylgeranyl)-6-methylquinol and 2′E,6′E)-2(10′,11′-dihydroxyeranylgeranyl)-6-methyl-1,4-benzoquinone have been isolated from the brown alga Cystoseira stricta. The structures of the new algal metabolites have been elucidated by spectral analysis and chemical degradation. 相似文献
73.
21 chemicals, known to induce missense and/or frameshift mutations directly, were assayed for their ability to forward mutate a haploid strain of A. nidulans. 2 genetic markers for forward mutations were used, namely 8-azaguanine resistance and induction of meth A1 suppressors. Missense mutagens were usually active when tested with the plate-incorporation technique, whereas frameshift agents were ineffective; some of these, on the other hand, turned out to be positive when tested with a liquid-test procedure. The 2 genetic markers used showed a similar sensitivity (with only 2 exceptions) in detecting the chemical mutagens assayed. 相似文献
74.
Daniela Belli Dell’Amico Author VitaeAuthor Vitae Guido Pampaloni Author Vitae 《Inorganica chimica acta》2008,361(11):2997-3003
Examples are reported of heavier (bromides or iodides) metal halides of the d or f transition series being prepared through the halide exchange reaction from the lighter congeners (fluorides or chlorides, easily prepared by direct combination from the elements), by using gaseous hydrogen halides HX or alkyl halides RX in an anhydrous organic solvent at room temperature or even below. This represents a considerable improvement with respect to the traditional high-temperature experimental procedures from the elements. Thermodynamic data show that this synthetic route is of quite general validity. 相似文献
75.
Offman J Gascoigne K Bristow F Macpherson P Bignami M Casorelli I Leone G Pagano L Sica S Halil O Cummins D Banner NR Karran P 《Molecular cancer research : MCR》2005,3(5):251-260
Microsatellite instability (MSI) in tumors is diagnostic for inactive DNA mismatch repair. It is widespread among some tumor types, such as colorectal or endometrial carcinoma, but is rarely found in leukemia. Therapy-related acute myeloid leukemia/myelodysplastic syndrome (tAML/MDS) is an exception, and MSI is frequent in tAML/MDS following cancer chemotherapy or organ transplantation. The development of MSI+ tumors is associated with an accumulation of insertion/deletion mutations in repetitive sequences. These events can cause inactivating frameshifts or loss of expression of key growth control proteins. We examined established MSI+ cell lines and tAML/MDS cases for frameshift-like mutations of repetitive sequences in several genes that have known, or suspected, relevance to leukemia. CASPASE-5, an acknowledged frameshift target in MSI+ gastrointestinal tract tumors, was frequently mutated in MSI+ cell lines (67%) and in tAML/MDS (29%). Frameshift-like mutations were also observed in the NF1 and FANCD2 genes that are associated with genetic conditions conferring a predisposition to leukemia. Both genes were frequent targets for mutation in MSI+ cell lines and colorectal carcinomas. FANCD2 mutations were also common in MSI+ tAML/MDS, although NF1 mutations were not observed. A novel FANCD2 polymorphism was also identified. 相似文献
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79.
Macpherson P Barone F Maga G Mazzei F Karran P Bignami M 《Nucleic acids research》2005,33(16):5094-5105
DNA 8-oxoguanine (8-oxoG) causes transversions and is also implicated in frameshifts. We previously identified the dNTP pool as a likely source of mutagenic DNA 8-oxoG and demonstrated that DNA mismatch repair prevented oxidation-related frameshifts in mononucleotide repeats. Here, we show that both Klenow fragment and DNA polymerase α can utilize 8-oxodGTP and incorporate the oxidized purine into model frameshift targets. Both polymerases incorporated 8-oxodGMP opposite C and A in repetitive DNA sequences and efficiently extended a terminal 8-oxoG. The human MutSα mismatch repair factor recognized DNA 8-oxoG efficiently in some contexts that resembled frameshift intermediates in the same C or A repeats. DNA 8-oxoG in other slipped/mispaired structures in the same repeats adopted configurations that prevented recognition by MutSα and by the OGG1 DNA glycosylase thereby rendering it invisible to DNA repair. These findings are consistent with a contribution of oxidative DNA damage to frameshifts. They also suggest how mismatch repair might reduce the burden of DNA 8-oxoG and prevent frameshift formation. 相似文献
80.
Bonanno JB Almo SC Bresnick A Chance MR Fiser A Swaminathan S Jiang J Studier FW Shapiro L Lima CD Gaasterland TM Sali A Bain K Feil I Gao X Lorimer D Ramos A Sauder JM Wasserman SR Emtage S D'Amico KL Burley SK 《Journal of structural and functional genomics》2005,6(2-3):225-232
Structural GenomiX, Inc. (SGX), four New York area institutions, and two University of California schools have formed the
New York Structural GenomiX Research Consortium (NYSGXRC), an industrial/academic Research Consortium that exploits individual
core competencies to support all aspects of the NIH-NIGMS funded Protein Structure Initiative (PSI), including protein family
classification and target selection, generation of protein for biophysical analyses, sample preparation for structural studies,
structure determination and analyses, and dissemination of results. At the end of the PSI Pilot Study Phase (PSI-1), the NYSGXRC
will be capable of producing 100–200 experimentally determined protein structures annually. All Consortium activities can
be scaled to increase production capacity significantly during the Production Phase of the PSI (PSI-2). The Consortium utilizes
both centralized and de-centralized production teams with clearly defined deliverables and hand-off procedures that are supported
by a web-based target/sample tracking system (SGX Laboratory Information Data Management System, LIMS, and NYSGXRC Internal
Consortium Experimental Database, ICE-DB). Consortium management is provided by an Executive Committee, which is composed
of the PI and all Co-PIs. Progress to date is tracked on a publicly available Consortium web site (http://www.nysgxrc.org)
and all DNA/protein reagents and experimental protocols are distributed freely from the New York City Area institutions. In
addition to meeting the requirements of the Pilot Study Phase and preparing for the Production Phase of the PSI, the NYSGXRC
aims to develop modular technologies that are transferable to structural biology laboratories in both academe and industry.
The NYSGXRC PI and Co-PIs intend the PSI to have a transforming effect on the disciplines of X-ray crystallography and NMR
spectroscopy of biological macromolecules. Working with other PSI-funded Centers, the NYSGXRC seeks to create the structural
biology laboratory of the future. Herein, we present an overview of the organization of the NYSGXRC and describe progress
toward development of a high-throughput Gene→Structure platform. An analysis of current and projected consortium metrics reflects
progress to date and delineates opportunities for further technology development. 相似文献