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1.
Charles Romeo Naoko Moriwaki Kerry T. Yasunobu Irwin C. Gunsalus Hideo Koga 《Journal of Protein Chemistry》1987,6(3):253-261
The first 12 NH2-terminal amino acids of the Pseudomonas putida putidaredoxin reductase were shown to be Met-Asn-Ala-Asn-Asp-Asn-Val-Val-Ile-Val-Gly-Thr. Comparison of these data with the DNA sequence of the BamHI-HindIII 197-base fragment derived from the PstI 2.2-kb fragment obtained from the P. putida plasmid showed that the putidaredoxin reductase gene was downstream from the cytochrome P-450 gene and the intergenic region had the 24-nucleotide sequence TAAACACATGGGAGTGCGTGCTAA. The Shine-Dalgarno sequence GGAG was detected in this region. The initiating triplet for the reductase gene was GTG, which normally codes for valine, but in the initiating codon position codes for methionine. From the amino acid sequence and X-ray data comparisons with other flavoproteins, what appears to be the AMP binding region of the FAD can be recognized in the NH2-terminal portion of the reductase involving residues 5–35.This article was presented during the proceedings of the International Conference on Macromolecular Structure and Function, held at the National Defence Medical College, Tokorozawa, Japan, December 1985. 相似文献
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The glutamate receptor-channel of locust muscle membrane was studied using the patch-clamp technique. Muscles were pretreated with concanavalin A to block receptor-channel desensitization, thus facilitating analysis of receptor-channel gating kinetics. Single channel kinetics were analyzed to aid in identification of the molecular basis of channel gating. Channel dwell-time distributions and dwell-time autocorrelation functions were calculated from single channel data recorded in the precence of 10-4M glutamate. Analysis of the dwell time distributions in terms of mixtures of exponential functions revealed there to be at least three open states of the receptor-channel and at least four closed states. Autocorrelation function analysis showed there to be at least three pathways linking the open states with the closed. This results in a minimal scheme for gating of the glutamate receptor-channel, which is suggestive of allosteric models of receptor-channel gating. 相似文献
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Batch ethanol fermentation by cells of Zymomomas mobilis ATCC 29191, ionically adsorbed on a DEAE-cellulose ion exchanger, was investigated in a stirred fermentor. Adsorption isotherms in different media were determined and used to interpret the effects of the environment on cell immobilization. Other factors affecting cell immobilization during an actual fermentation were studied. Mechanical agitation was found to cause detachment of cells from the ion exchange particles. The results suggest that the amount of cells adsorbed during a fermentation process is different from that found from adsorption isotherm data. Consequently, application of equilibrium adsorption data to actual fermentations should be done with caution. 相似文献
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Kerry Barringer 《Brittonia》1987,39(3):353-357
Agalinis bandeirensis is a Brazilian species distinguished by linear bracts, short pedicels, and villous stamens.Agalinis ramulifera, from southern Brazil, is distinguished by many, short, leafy branches and small flowers.Agalinis linarioides subsp.rojasi, from Paraguay, is distinguished by paniculate inflorescences, short calyx lobes, and broad corollas.Gerardia bangii, G. digitalis, andG. meyeniana are recognized as species ofAgalinis and appropriate transfers are made. 相似文献
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Twenty-two patients with roping injuries to 38 digits, including 19 patients injured while team roping, are discussed. Ten digits in nine patients were successfully revascularized or replanted. Seven digits in three patients failed after initial success. One patient is included in both categories. The failure rate is 41 percent for all 17 digits. Average follow-up is 18 months. The dominant hand was injured in 83 percent of team roping injuries; the thumb is the most commonly injured digit. Average interphalangeal motion for thumb replants is zero; for revascularizations, it is 47 degrees. There was 43 percent return of pinch strength for thumb replants compared to 83 percent return for a single thumb revascularization. The most common mechanism of injury was catching the roping thumb in the "thumb up" position during dallying. There are good motion and pinch strength with thumb revascularizations provided tendons and the interphalangeal joint are intact. Reconstruction of the flexor pollicis longus in the replanted thumb gave poor results. Primary tenodesis or arthrodesis is recommended. 相似文献
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Kerry Barringer 《Brittonia》1986,38(2):128-132
Aristolochia fosteri is a new species with unusual branched trichomes collected in Pasco near Oxapampa.Aristolochia hutchisonii is a prostrate species found in Amazonas and Cajamarca that is related toA. weberbaueri.Aristolochia barbouri is a narrow-leaved, herbaceous liana from Madre de Dios. 相似文献
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Kerry Barringer 《Brittonia》1985,37(3):286-290
Elleanthus stolonifer andE. tillandsioides are new species in theE. poiformis complex of sectionChloidelyna.Elleanthus lentii is a new species in sectionStachydelyna. Elleanthus stolonifer is widespread in the mountains of Costa Rica and Panama;E. tillandsioides is found only in the lowland forests of southeastern Costa Rica;E. lentii is limited to the Cordillera de Guanacaste of Costa Rica. 相似文献
10.
Kerry Barringer 《Brittonia》1985,37(2):195-198
Barringer, Kerry (Department of Botany, Field Museum of Natural History, Chicago, IL 60605). Two new species of Esterhazya (Scrophulariaceae) from Brazil. Brittonia 37: 195–198. 1985.—Esterhazya petiolata is a distinctive species with ovate, petiolate leaves, spreading brances, and broadly tubular-campanulate flowers. It is known from the Serra Dourada of Goiás. Esterhazya eitenorum has narrow, lanceolate leaves, acute calyx lobes, and purple-pink flowers and is known from the planalto of Mt. Itatiaia. 相似文献