Indole-3-Acetic Acid Biosynthesis in the Mutant Maize orange pericarp, a Tryptophan Auxotroph     

Wright AD  Sampson MB  Neuffer MG  Michalczuk L  Slovin JP  Cohen JD 《Science (New York, N.Y.)》1991,254(5034):998-1000

The maize mutant orange pericarp is a tryptophan auxotroph, which results from mutation of two unlinked loci of tryptophan synthase B. This mutant was used to test the hypothesis that tryptophan is the precursor to the plant hormone indole-3-acetic acid (IAA). Total IAA in aseptically grown mutant seedlings was 50 times greater than in normal seedlings. In mutant seedlings grown on media containing stable isotopelabeled precursors, IAA was more enriched than was tryptophan. No incorporation of label into IAA from tryptophan could be detected. These results establish that IAA can be produced de novo without tryptophan as an intermediate.  相似文献   

Peat bogs     

Wright HE  Janssens JA 《Science (New York, N.Y.)》1982,216(4546):616-617

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Transport of Dissolved Amino Acids by the Mussel, Mytilus edulis: Demonstration of Net Uptake from Natural Seawater     

Manahan DT  Wright SH  Stephens GC  Rice MA 《Science (New York, N.Y.)》1982,215(4537):1253-1255

High-performance liquid chromatography provides direct evidence for substantial removal of naturally occurring specific free amino acids during a single passage of water through the mantle cavity of mussels. This occurs during the few seconds required for passage of the water across the gill, and removal proceeds unabated at ambient substrate concentrations as low as 38 nanomoles per liter.  相似文献   

Coal science: basic research opportunities     

Gorbaty ML  Wright FJ  Lyon RK  Long RB  Schlosberg RH  Baset Z  Liotta R  Silbernagel BG  Neskora DR 《Science (New York, N.Y.)》1979,206(4422):1029-1034

More fundamental knowledge of coal (knowledge of its structure and its behavior during conversion processes) is essential before we can generate new technologies necessary for the efficient use of coal in the future. Herein are suggested specific basic research opportunities in the areas of coal characterization, gasification, combustion, and liquefaction, along with an assessment of the impact such research programs could have. Critical characterization needs include qualitative and quantitative determination of the chemical forms of carbon, oxygen, nitrogen, and sulfur and reliable methods for the measurement of surface area, pore volume, and weight-average molecular weights. Mechanistic studies aimed at increasing understanding of the thermal breakdown of the functionalities in coal, the behavior of coal in the presence of molecular and donor hydrogen environments, and carbon gasification and hydrocarbon synthesis reactions starting from carbon monoxide and hydrogen will lay the scientific foundation for the development of new processes for converting coal into clean usable fuels and chemicals.  相似文献   

The chinese quaternary: quaternary geology and environment of china     

Wright HE 《Science (New York, N.Y.)》1986,231(4740):874

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River delta morphology: wave climate and the role of the subaqueous proffile     

Wright LD  Coleman JM 《Science (New York, N.Y.)》1972,176(4032):282-284

Application of a comprehensive wave climate program to seven major deltas indicates that deltaic configurations and coastal landform combinations depend to a considerable degree on the wave power adjacent to the shore and on the river discharge relative to wave forces. Nearshore wave power is not correlative with deepwater wave power but, owing to frictional attenuation, is a function of the subaqueous slope. The subaqueous slope, in turn, depends partially on the slope and width of the continental shelf but primarily on the rate at which the river can supply sediments to the nearshore zone. River-dominated configurations result only when the river is able to build flat offshore profiles, which reduce nearshore wave power; where the subaqueous slope is steep, waves reach the shore comparatively undiminished and wave-built forms prevail.  相似文献   

Bad news bacteria     

K Wright 《Science (New York, N.Y.)》1990,249(4964):22-24

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Planning the genome institute's future     

Uhlmann WR  Bennett R  Botkin JR  Botstein D  Boughman JA  Chakravarti A  Clayton EW  Kahn J  Koenig B  Murray TH  Olson MV  Rowley J  Terry S  Valle D 《Science (New York, N.Y.)》2003,299(5612):1515; author reply 1515

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Biochemistry. A new target for antibiotic development     

Wright GD 《Science (New York, N.Y.)》2007,315(5817):1373-1374

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PRESENT AND POST-WAR HEALTH PROBLEMS IN CONNECTION WITH PARASITIC DISEASES     

Wright WH 《Science (New York, N.Y.)》1944,99(2568):207-213

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