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91.
Cellular Fatty Acid Composition of Selected Pseudomonas Species   总被引:17,自引:4,他引:13       下载免费PDF全文
The cellular fatty acid composition of 10 reference strains representing eight species of Pseudomonas was determined by gas-liquid chromatography. A variety of acids were detected in these organisms, including branched and straight-chained acids, cyclopropane, and hydroxy acids. Comparison of the presence and relative amounts of these acids among strains was useful for distinguishing various Pseudomonas species.  相似文献   
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93.
The state of chlorophyll in chloroplast fragments is affected by such factors as the ionic strength and pH of the suspending medium. With increasing ionic strength or at pH values other than neutrality, there is a decrease in the fluorescence yield of the form of chlorophyll with fluorescence maximum at 715 to 736 mμ (aggregate) and an increase in the yield of the form with fluorescence maximum at 685 mμ (monomer). (Positions of maxima cited are for 77°K.) These changes in yield are accompanied by modifications in absorption and fluorescence excitation spectra. It is also noted that these effects are similar to the ones brought about by pancreatic lipase, wheat germ lipase, pancreatic trypsin or urea. An interpretation is given which is consistent with the experimental data, namely, that the effects originate in conformational changes in the proteins to which the pigments are attached. These conformational changes give rise to an increase in the size of the aggregate and a decrease in the probability of energy transfer between the monomer and aggregates.  相似文献   
94.
The devastating Indian Ocean tsunami of 26 December 2004 caused massive destruction to coastal Aceh, Indonesia, and left countless numbers of people dead or wounded. This article focuses on the embodied narratives of three Acehnese women who survived the disaster and, like many others in Aceh, told their stories ‘through’ their bodies. A detailed ethnographic account of their narratives reveals how the body stretches temporally between the ‘narrated event’ and the ‘narrative event’, both through the representation of the body in narratives and through the embodied performance of narratives. Moving beyond meaning‐centred analyses of narratives, I argue that the central accomplishment of these narratives is that they convey poignant bodily experiences to others and thereby create a shared, post‐disaster, world. Ultimately, through these embodied narratives of disaster people remake their world, with others, in the wake of its ‘unmaking’.  相似文献   
95.
Trichoderma (Ascomycetes, Hypocreales) strains that have warted conidia are traditionally identified as T. viride, the type species of Trichoderma. However, two morphologically distinct types of conidial warts (I and II) have been found. Because each type corresponds to a unique mitochondrial DNA pattern, it has been questioned whether T. viride comprises more than one species. Combined molecular data (sequences of the internal transcribed spacer 1 [ITS-1] and ITS-2 regions and of part of the 28S rRNA gene along with results of restriction fragment length polymorphism analysis of the endochitinase gene and PCR fingerprinting), morphology, physiology, and colony characteristics distinguish type I and type II as different species. Type I corresponds to “true” T. viride, the anamorph of Hypocrea rufa. Type II represents a new species, T. asperellum, which is, in terms of molecular characteristics, close to the neotype of T. hamatum.  相似文献   
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Plant ABC proteins--a unified nomenclature and updated inventory   总被引:5,自引:0,他引:5  
The ABC superfamily comprises both membrane-bound transporters and soluble proteins involved in a broad range of processes, many of which are of considerable agricultural, biotechnological and medical potential. Completion of the Arabidopsis and rice genome sequences has revealed a particularly large and diverse complement of plant ABC proteins in comparison with other organisms. Forward and reverse genetics, together with heterologous expression, have uncovered many novel roles for plant ABC proteins, but this progress has been accompanied by a confusing proliferation of names for plant ABC genes and their products. A consolidated nomenclature will provide much-needed clarity and a framework for future research.  相似文献   
98.

Background  

Nervous tissues express various communication molecules including natriuretic peptides, i.e. Brain Natriuretic Peptide (BNP) and C-type Natriuretic Peptide (CNP). These molecules share structural similarities with cyclic antibacterial peptides. CNP and to a lesser extent BNP can modify the cytotoxicity of the opportunistic pathogen Pseudomonas aeruginosa. The psychrotrophic environmental species Pseudomonas fluorescens also binds to and kills neurons and glial cells, cell types that both produce natriuretic peptides. In the present study, we investigated the sensitivity of Pseudomonas fluorescens to natriuretic peptides and evaluated the distribution and variability of putative natriuretic peptide-dependent sensor systems in the Pseudomonas genus.  相似文献   
99.

Background  

Pseudomonas fluorescens is a ubiquitous Gram-negative bacterium frequently encountered in hospitals as a contaminant of injectable material and surfaces. This psychrotrophic bacterium, commonly described as unable to grow at temperatures above 32°C, is now considered non pathogenic. We studied a recently identified clinical strain of P. fluorescens biovar I, MFN1032, which is considered to cause human lung infection and can grow at 37°C in laboratory conditions.  相似文献   
100.
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