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排序方式: 共有172条查询结果,搜索用时 15 毫秒
1.
Carole L. Harker Philip M. Mullineaux John A. Bryant Andrew J. Maule 《Plant molecular biology》1987,8(3):275-287
Specific antisera were prepared to the inclusion body protein (gene VI product) and the gene I product of cauliflower mosaic virus (CaMV). Translational fusions between the lacZ gene and gene VI or gene I were constructed by cloning the relevant DNA fragments into the expression vectors pUR290, pUR291 or pUR292. Large amounts of fusion protein were synthesized when the inserted DNA fragment was in frame with the lacZ gene of the expression vector. These fusion proteins were used to raise specific antisera to gene VI and gene I proteins of CaMV. Antiserum to the gene VI product detected a range of proteins in crude extracts and in a subcellular fraction enriched for virus inclusion bodies. This range of proteins was further shown to be related to gene VI by Staphylococcus aureus V8 partial proteolysis. Antiserum to the gene I product detected viral specific proteins of 46, 42 and 38 K in preparations of CaMV replication complexes from infected plants but not in any other subcellular fraction. 相似文献
2.
The nervous system of Tricladida. I. Neuroanatomy ofProcerodes littoralis (Maricola,Procerodidae): An immunocytochemical study 总被引:3,自引:0,他引:3
Maria Reuter Margaretha K. S. Gustafsson Cecilia Sahlgren David W. Halton Aaron G. Maule Chris Shaw 《Invertebrate neuroscience : IN》1995,1(2):113-122
The organization of the nervous system ofProcerodes littoralis (Tricladida, Maricola, Procerodidae) was studied by immunocytochemistry, using antibodies to authentic flatworm neuropeptide
F (NPF) (Moniezia expansa). Compared to earlier investigations of the neuroanatomy of tricladid flatworms, the pattern of NPF immunoreactivity inProcerodes littoralis reveals differences in the following respects: 1. Shape and structure of the brain. 2. Number and composition of longitudinal
nerve cords. 3. Shape of branches of, and transverse connections between, main ventral nerve cords. 4. Composition of the
pharyngeal nervous system. The rich innervation by NPF immunoreactive (IR) fibres and cells of the subepithelial muscle layer,
the pharynx musculature and the musculature of the male copulatory apparatus indicates a neurotransmitter or neuromodulatory
influence on muscular activity. 相似文献
3.
The nervous system of Tricladida. II. Neuroanatomy ofDugesia tigrina (Paludicola,Dugesiidae): An immunocytochemical study 总被引:2,自引:0,他引:2
4.
Purification and preliminary characterization of permethrinase from a pyrethroid-transforming strain of Bacillus cereus. 总被引:7,自引:0,他引:7 下载免费PDF全文
Bacillus cereus SM3 was isolated on a mineral salts medium with Tween 80 as the primary carbon source. It was able to hydrolyze second- and third-generation pyrethroids, thereby generating noninsecticidal products. The enzyme responsible for this hydrolytic reaction was named permethrinase for this study. This is the first instance in which pyrethroid detoxification has been achieved with a cell-free microbial enzyme system. Permethrinase was purified by ion-exchange chromatography and gel filtration chromatography. The molecular mass of native permethrinase was 61 +/- 3 kDa, as estimated by Sephadex G-100 gel filtration. This novel microbial esterase seems to be a carboxylesterase. Permethrinase activity had an optimum pH of 7.5 and a temperature optimum of 37 degrees C. No cofactors or coenzymes were required for permethrinase activity. The enzyme may be a serine esterase, as it seems to be sensitive to the organophosphorus compound tetraethylpyrophosphate at concentrations in the micromolar range. Addition of dithiothreitol afforded permethrinase protection against the inhibitory effects of the sulfydryl agents p-chloromercuribenzoate and N-ethylmaleimide. The enzyme was stable over a range of temperatures. Cell extracts of strain SM3 also contained another esterase, which was active towards beta-naphthylacetate, but this enzyme was distinct from permethrinase. 相似文献
5.
6.
Osvaldo Mutchinick Lizbeth Ruz María E. Gonsebatt Patricia Mauleón Rubén Lisker Guillermo García 《Human genetics》1981,59(2):137-140
Summary Induced and spontaneous structural chromosome aberrations (SCA) were studied in a child accidentally radiated with a high dose of 192Ir, and in three sibs with Fanconi's anemia, analyzing by separate first division metaphases (FDM) and second division metaphases (SDM). The results showed that the number of SCA, number of cells with aberrations, and SCA per cell were markedly higher in FDM in all patients.Furthermore, for some type of structural changes like dicentric chromosomes and chromatid interchanges, the differences were particularly striking. The importance of ascertaining FDM identified with proper techniques, for the study of the clastogenic effect of environmental agents and some aspects related to the differences in cytogenetic features found in diverse tissues in Fanconi's anemia are discussed. 相似文献
7.
Porphyrins and corrins have been immobilized onto solid-phase supports and used to dehalogenate organohalides under reducing conditions. One such system has been used to dehalogenate an aqueous solution (10 ppm) of lindane for over 90 days at over 98% efficiency and for a further 150 days in excess of 65% efficiency. Dichloromethane has been shown to be effectively dehalogenated when supplied to immobilized systems in gaseous form.
Correspondence to: T. S. Marks 相似文献
8.
Summary A lambda transducing phage carrying the traGSTD genes of the E. coli K12 sex factor F was isolated by an in vivo technique, and characterized in ra complementation tests, by determining its restriction endonuclease fragment sizes, and by measuring heteroduplex molecules. The size and location on the F physical map of the tra transducing segment was thereby determined.Comparison of the proteins synthesized in UV-irradiated cells by this phage and by a derivative carrying the amber traG79 mutation, allowed the traG product to be identified as a protein of molecular weight 100,000. In the same experiments, the sizes of the traT and traD products made by the phage were also measured, being 25,000 and 85,000 daltons respectively. 相似文献
9.
Compromised heat shock protein 90 (Hsp90) function reveals cryptic phenotypes in flies and plants. These observations were interpreted to suggest that this molecular stress-response chaperone has a capacity to buffer underlying genetic variation. Conversely, the protective role of Hsp90 could account for the variable penetrance or severity of some heritable developmental malformations in vertebrates. Using zebrafish as a model, we defined Hsp90 inhibitor levels that did not induce a heat shock response or perturb phenotype in wild-type strains. Under these conditions the severity of the recessive eye phenotype in sunrise, caused by a pax6b mutation, was increased, while in dreumes, caused by a sufu mutation, it was decreased. In another strain, a previously unobserved spectrum of severe structural eye malformations, reminiscent of anophthalmia, microphthalmia, and nanophthalmia complex in humans, was uncovered by this limited inhibition of Hsp90 function. Inbreeding of offspring from selected unaffected carrier parents led to significantly elevated malformation frequencies and revealed the oligogenic nature of this phenotype. Unlike in Drosophila, Hsp90 inhibition can decrease developmental stability in zebrafish, as indicated by increased asymmetric presentation of anophthalmia, microphthalmia, and nanophthalmia and sunrise phenotypes. Analysis of the sunrise pax6b mutation suggests a molecular mechanism for the buffering of mutations by Hsp90. The zebrafish studies imply that mild perturbation of Hsp90 function at critical developmental stages may underpin the variable penetrance and expressivity of many developmental anomalies where the interaction between genotype and environment plays a major role. 相似文献