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61.
W H Fischer 《Science (New York, N.Y.)》1971,171(973):828-829
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Garcia-Mira MM Sadqi M Fischer N Sanchez-Ruiz JM Muñoz V 《Science (New York, N.Y.)》2002,298(5601):2191-2195
Theory predicts the existence of barrierless protein folding. Without barriers, folding should be noncooperative and the degree of native structure should be coupled to overall protein stability. We investigated the thermal unfolding of the peripheral subunit binding domain from Escherichia coli's 2-oxoglutarate dehydrogenase multienzyme complex (termed BBL) with a combination of spectroscopic techniques and calorimetry. Each technique probed a different feature of protein structure. BBL has a defined three-dimensional structure at low temperatures. However, each technique showed a distinct unfolding transition. Global analysis with a statistical mechanical model identified BBL as a downhill-folding protein. Because of BBL's biological function, we propose that downhill folders may be molecular rheostats, in which effects could be modulated by altering the distribution of an ensemble of structures. 相似文献
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Chien M Morozova I Shi S Sheng H Chen J Gomez SM Asamani G Hill K Nuara J Feder M Rineer J Greenberg JJ Steshenko V Park SH Zhao B Teplitskaya E Edwards JR Pampou S Georghiou A Chou IC Iannuccilli W Ulz ME Kim DH Geringer-Sameth A Goldsberry C Morozov P Fischer SG Segal G Qu X Rzhetsky A Zhang P Cayanis E De Jong PJ Ju J Kalachikov S Shuman HA Russo JJ 《Science (New York, N.Y.)》2004,305(5692):1966-1968
We present the genomic sequence of Legionella pneumophila, the bacterial agent of Legionnaires' disease, a potentially fatal pneumonia acquired from aerosolized contaminated fresh water. The genome includes a 45-kilobase pair element that can exist in chromosomal and episomal forms, selective expansions of important gene families, genes for unexpected metabolic pathways, and previously unknown candidate virulence determinants. We highlight the genes that may account for Legionella's ability to survive in protozoa, mammalian macrophages, and inhospitable environmental niches and that may define new therapeutic targets. 相似文献
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Siegenthaler U Stocker TF Monnin E Lüthi D Schwander J Stauffer B Raynaud D Barnola JM Fischer H Masson-Delmotte V Jouzel J 《Science (New York, N.Y.)》2005,310(5752):1313-1317
A record of atmospheric carbon dioxide (CO2) concentrations measured on the EPICA (European Project for Ice Coring in Antarctica) Dome Concordia ice core extends the Vostok CO2 record back to 650,000 years before the present (yr B.P.). Before 430,000 yr B.P., partial pressure of atmospheric CO2 lies within the range of 260 and 180 parts per million by volume. This range is almost 30% smaller than that of the last four glacial cycles; however, the apparent sensitivity between deuterium and CO2 remains stable throughout the six glacial cycles, suggesting that the relationship between CO2 and Antarctic climate remained rather constant over this interval. 相似文献