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241.
Claudia?Klinger Michael?Ro?bach Rebecca?Howe Michael?KaufmannEmail author 《BMC biochemistry》2003,4(1):12
Background
To identify thermophile-specific proteins, we performed phylogenetic patterns searches of 66 completely sequenced microbial genomes. This analysis revealed a cluster of orthologous groups (COG1618) which contains a protein from every thermophile and no sequence from 52 out of 53 mesophilic genomes. Thus, COG1618 proteins belong to the group of thermophile-specific proteins (THEPs) and therefore we here designate COG1618 proteins as THEP1s. Since no THEP1 had been analyzed biochemically thus far, we characterized the gene product of aq_1292 which is THEP1 from the hyperthermophilic bacterium Aquifex aeolicus (aaTHEP1). 相似文献242.
Parish RV Howe BP Wright JP Mack J Pritchard RG Buckley RG Elsome AM Fricker SP 《Inorganic chemistry》1996,35(6):1659-1666
Several new organogold(III) derivatives of the type [AuX(2)(damp)] (damp = o-C(6)H(4)CH(2)NMe(2)) have been prepared [X = CN, SCN, dtc, or X(2) = tm; dtc = R(2)NCS(2) (R = Me (dmtc) or Et (detc)); tm = SCH(CO(2))CH(2)CO(2)Na] together with [AuCl(tpca)(damp)]Cl (tpca = o-Ph(2)PC(6)H(4)CO(2)H), [Au(dtc)(damp)]Y (Y = Cl, BPh(4)) and K[Au(CN)(3)(damp)]. The (13)C NMR spectra of these and previous derivatives have been fully assigned. In [Au(dtc)(2)(damp)] and K[Au(CN)(3)(damp)], the damp ligand is coordinated only through carbon, as shown by X-ray crystallography and/or NMR. [Au(detc)(2)(damp)] has space group C2/c, with a = 29.884(4) ?, b = 13.446(2) ?, c = 12.401(2) ?, beta = 99.45(3)(o), V = 4915 ?(3), Z = 8, and R = 0.057 for 1918 reflections. The damp and one detc ligand are monodentate, the other detc is bidentate; in solution, the complex shows dynamic behavior, with the detc ligands appearing equivalent. The crystal structure of [Au(dmtc)(damp)]BPh(4) [Pna2(1), a = 26.149(5) ?, b = 11.250(2) ?, c = 11.921(2) ?, V = 3507 ?(3), Z = 4, R = 0.073, 1772 reflections] shows both ligands to be bidentate in the cation, but the two Au-S distances are nonequivalent. The crystal structure of [Au(tm)(damp)] has also been determined [P2(1)/n, a = 18.267(7) ?, b = 9.618(3) ?, c = 18.938(4) ?, beta = 113.45(3)(o), V = 3053 ?(3), Z = 8, R = 0.079, 1389 reflections]. The tm is bound through sulfur and the carboxyl group which allows five-membered ring formation. In all three structures, the trans-influence of the sigma-bonded aryl group is apparent. [AuCl(2)(damp)] has been tested in vitroagainst a range of microbial strains and several human tumor lines, where it displays differential cytotoxicity similar to that of cisplatin. Against the ZR-75-1 human tumor xenograft, both [AuCl(2)(damp)] and cisplatin showed limited activity. 相似文献
243.
244.
The simplicial complexK(A) is defined to be the collection of simplices, and their proper subsimplices, representing maximal lattice free bodies of the form (x: Axb), withA a fixed generic (n + 1) ×n matrix. The topological space associated withK(A) is shown to be homeomorphic to
n
, and the space obtained by identifying lattice translates of these simplices is homeorphic to then-torus.Corresponding author.The first author was partially supported by Hungarian NSF grants 1907 and 1909, and also by U.S. NSF grant CCR-9111491. The research of the second author was supported by DMS9103608 and the third author by NSF grant SES9121936. 相似文献
245.
Shanmugasundaram Veerabahu Bajorath Jürgen Christoffersen Ralph E. Petke James D. Howe W. Jeffrey Johnson Mark A. Agrafiotis Dimitris K. Lee Pil Kuhn Leslie A. Goodwin Jay T. Holloway M. Katharine Doman Thompson N. Walters W. Patrick Schreyer Suzanne Medina-Franco José L. Martinez-Mayorga Karina Restifo Linda L. 《Journal of computer-aided molecular design》2022,36(9):623-638
Journal of Computer-Aided Molecular Design - In May 2022, JCAMD published a Special Issue in honor of Gerald (Gerry) Maggiora, whose scientific leadership over many decades advanced the fields of... 相似文献
246.
A review is given of recent work in the authors' laboratory on the characterization of different forms of nanostructured titania.
It is shown that nanocrystalline anatase powders and nanocrystalline anatase thin films differ significantly in their optical
properties, due primarily to differences in sintering behaviour on drying. It is argued that the electronic properties of
these systems are determined by surface phenomena rather than quantum size effects. The novel titanosilicate zeolite ETS-10
which contains one dimensional “quantum wires” of titania provides an alternative system for studying quantum size effects
which has considerable potential for photocatalysis. 相似文献
247.
Susan E. Howe C. M. Davidson Martin McCartney 《Analytical and bioanalytical chemistry》1999,363(5-6):582-584
Uranium was determined in extracts of inter-tidal sediment, obtained from a contaminated harbour, using the three-stage sequential extraction procedure recommended by BCR. The element was found mainly in association with reducible, or reducible and oxidisable, phases and the overall concentration was enhanced (up to 6.7 μg g–1 dry weight) with respect to typical, UK levels. The 238U/235U ratio has been measured in digests of stream sediments obtained from the vicinity of a uranium enrichment plant. Significant enhancement in 235U with respect to the natural 238U/235U ratio (137.88:1) was observed at some locations. 相似文献
248.
van Howe J Lee JH Zhou S Wise F Xu C Ramachandran S Ghalmi S Yan MF 《Optics letters》2007,32(4):340-342
We demonstrate soliton self-frequency shift of more than 12% of the optical frequency in a higher-order mode solid, silica-based fiber below 1300nm. This new class of fiber shows great promise for supporting Raman-shifted solitons below 1300nm in intermediate energy regimes of 1 to 10nJ that cannot be reached by index-guided photonic crystal fibers or air-core photonic bandgap fibers. By changing the input pulse energy of 200fs pulses from 1.36 to 1.63nJ we observe Raman-shifted solitons between 1064 and 1200nm with up to 57% power conversion efficiency and compressed output pulse widths less than 50fs. Furthermore, due to the dispersion characteristics of the HOM fiber, we observe redshifted Cerenkov radiation in the normal dispersion regime for appropriately energetic input pulses. 相似文献
249.
250.
Alber T Appelshäuser H Bächler J Bartke J Bialkowska H Bieser F Bloomer MA Blyth CO Bock R Bormann C Brady FP Brockmann R Buncic P Caines HL Cebra D Chan P Cooper GE Cramer JG Cramer PB Csato P Derado I Dunn J Eckardt V Eckhardt F Euler S Ferguson MI Fischer HG Fodor Z Foka P Freund P Fuchs M Gal J Gazdzicki M Gladysz E Grebieszkow J Günther J Harris JW Heck W Hegyi S Hill LA Huang I Howe MA Igo G Irmscher D Jacobs P Jones PG Kadija K Kecskemeti J Kowalski M Kühmichel A Lasiuk B Margetis S 《Physical review letters》1995,75(21):3814-3817