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941.
942.
943.
Outer membrane proteins of Pseudomonas   总被引:26,自引:0,他引:26  
In this review, we describe the outer membrane proteins of Pseudomonas aeruginosa and related strains from the Pseudomonas fluorescens rRNA homology group of the Pseudomonadaceae, with emphasis on the physiological function and biochemical characteristics of these proteins. The use of opr (for outer membrane protein) is proposed as the genetic designation for the P. aeruginosa outer membrane proteins and letters are assigned, in conjunction with this designation, to known outer membrane proteins. Proteins whose primary functions involve pore formation, transport of specific substrates, cell structure determination and membrane stabilization are discussed. The conservation of selected proteins in the above Pseudomonas species is also examined.  相似文献   
944.
The results of complementation analysis of nitrosoguanidine-induced mutants of F-like drd-plasmid pAP18-1 (Tc, ColV) testified to the existence of at least 3 tra regions (tra1, tra2, tra3) and regulating locus fin V in the genome of this plasmid. By means of molecular cloning of tra2 region and locus fin V of plasmid pAP18-1drd were located in Sall-fragment f5 (3.9 MD).  相似文献   
945.
Ombuin (7,4′-dimethyl quercetin) (10 μg ml-1, for 12 wk), glycyrrhizin/quercetin (80 μg ml-1and 10 μg ml-1respectively, for 18 wk), ribavirin (10 μg ml-1, for 12 wk) and quercetin/ribavirin (10 μg ml-1each, for 9–12 wk) reduced the titre of apple stem grooving virus (ASGV) when applied in vitro to infected tissue cultures of Nicotiana occidentalis obliqua Wheeler, and/or Malus domestica. ASGV was not detectable in both plant species after the quercitin/ribavirin treatment when tested by ISEM, herbaceous host indexing, RT-PCR, and immunocapture RT-PCR. A sensitive immunocapture RT-PCR procedure for the detection of ASGV was developed for the screening of treated samples to assess antiviral activity.  相似文献   
946.
947.
The phytocenotic diversity of the Altai steppe piedmont is described. Plant communities were ordinated along the moisture gradient. The results were used to analyze the structure of vegetation of steppe hill massifs. Distribution of steppe vegetation over an ideal hill was simulated, and the main patterns of distribution were typified.  相似文献   
948.
Lipid synthesis in permeabilized cultured rat hepatocytes   总被引:1,自引:0,他引:1  
Hepatic lipid synthesis was verified and studied in lysolecithin-permeabilized cultured rat hepatocytes and compared to that of intact liver cells. Triacylglycerol synthesis in permeabilized cells incubated in the presence of glycerol 3-phosphate and long chain fatty acids approached that of intact hepatocytes. Similarly, phosphatidylcholine synthesis in permeable cells incubated in the presence of exogenous CDP-choline was similar to that of intact hepatocytes and at the expense of microsomal neutral lipid synthesis. Phosphatidic acid accumulation in lysolecithin-permeabilized liver cells was remarkably increased as compared to that of intact cells, and its synthesis was mostly accounted for by the activity of mitochondrial glycerol-3-phosphate acyltransferase. Mitochondrial-generated phosphatidate was found to migrate to the endoplasmic reticulum, thus establishing a novel lipid esterification pathway which begins in mitochondrial glycerol 3-phosphate acylation and results in microsomal triacylglycerol and phospholipid synthesis. The free access of permeabilized liver cells to substrates and modulators of lipid synthesis, while maintaining an overall synthetic pattern similar to that of intact hepatocytes, makes them a system of choice for studying hepatic lipid synthesis in general and the microsomal/mitochondrial distribution of fluxes in particular.  相似文献   
949.
N.C. Lee 《CMAJ》1990,142(11):1176-1177
  相似文献   
950.
Yellow lupine seeds were found to contain two proteins and a low molecular weight fraction possessing the ability to bind Mo, W and radionuclides from the Chernobyl nuclear power in vivo and the 185W isotope in vitro. These proteins differ in their electrophoretic mobility. The electrophoretically less mobile protein undergoes proteolytic degradation; the proteolytic product retains the ability to accumulate microelements.  相似文献   
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