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161.
Maria L. Bade Alfred Stinson 《Biochemical and biophysical research communications》1978,84(2):381-388
During the molt, chitin in the old cuticle of is digested by chitinase taken up from molting fluid, but the chitin in intact (= premolt) cuticle is not accessible to chitinase. As a prerequisite of digestion, old cuticle chitin is rendered competent to serve as chitinase substrate in a reaction attributable to trypsin-like proteolytic activity of molting fluid. 相似文献
162.
Anna Radomińska-Pyrek Maria Pilarska Piotr Zimniak 《Biochemical and biophysical research communications》1978,85(3):1074-1081
Phosphoethanolaminetransferase of high specific activity was solubilized from rat liver microsomes with the non-ionic detergent octyl glucoside. The solubilization method is fast and simple, allowing for processing of large amounts of material. The solubilized enzyme is stable. It contains virtually no phosphocholinetransferase activity. A preliminary characterization of the enzyme, with both diacyl- and alkylacyl-glycerol as substrate, is given. For the reaction, the lipid substrates were incorporated into artificial phospholipid bilayers (liposomes). 相似文献
163.
Derek Jones Giuseppe Disteffano Claudio Toniolo Gian Maria Bonora 《Biopolymers》1978,17(11):2703-2713
The problem of the quantitative determination of sulfoxide groups in peptide molecules has been re-examined. The approaches currently available for the estimation of δ-sulfoxide amino acids are limited in number and characterized by serious shortcomings; in addition, the choice of methods for the estimation of γ-sulfoxide amino acids is even more restricted. A new, rapid, and nondestructive direct method for determining quantitatively all types of sulfoxides in peptide molecules by using x-ray photoelectron spectroscopy is described. 相似文献
164.
Giovanni Vidari Maria De Bernardi Paola Vita-Finzi Giovanni Fronza 《Phytochemistry》1976,15(12):1953-1955
Six sesquiterpene lactones were isolated from Lactarius blennius. The structures of two new sesquiterpenes, blennin A and blennin B were determinated by spectroscopic methods and the structure of the seco-compound, blennin C, is revised. The two known furan sesquiterpenes and lactarorufin A were also identified. 相似文献
165.
Maria A. A. Schipper 《Antonie van Leeuwenhoek》1976,42(1-2):141-144
Attempts to determine the mating reaction type of heterothallic strains of Mucor pusillus in interspecific contrasts with Mucor strains of known mating reaction type were unsuccessful. Contrasts with Absidia corymbifera strains resulted in the production of azygospores in Mucor pusillus. 相似文献
166.
Alessandro Bruni Maria P. Fasulo Barbara Tosi Giuseppe Dall'Olio Gian Luigi Vannini 《Histochemistry and cell biology》1976,48(4):269-281
Summary The new highly sensitive method of fluorescamine reaction for the topochemical detection of primary amino groups was studied as a substitude of ninhydrin-Schiff's reaction for the localisation of total proteins in plant tissues. The influence of various coagulant and non-coagulatn fixatives on the induction of fluorescamine fluorescence was examined: ethanol, formaldehyde gas and solution, glutaraldehyde, acrolein, osmium tetroxide, Bouin, Rossman, Clarke and Zenker's fluids and FMA were employed. It was found that the use of the fluorogenic method is conditioned by the fixative ability to keep the amino groups disposable and by its capability to reduce the natural autofluorescence of plant material. A detailed account of the fixation methodology demonstrated that non-coagulant acrolein and coagulant mercuric chloride are the most promising fixatives for the use of the fluorescamine reaction in plant histochemistry. 相似文献
167.
A new method of in situ hybridization 总被引:27,自引:0,他引:27
Jerry E. Manning N. Davis Hershey Thomas R. Broker Maria Pellegrini Herschel K. Mitchell Norman Davidson 《Chromosoma》1975,53(2):107-117
A new method for gene mapping at the chromosome level using in situ hybridization and scanning electron microscopy is described and has been applied to mapping the rRNA genes of Drosophila melanogaster. Biotin is covalently attached to Drosophila rRNA via a cytochrome c bridge at a ratio of one cytochrome-biotin per 130 nucleotides by a chemical procedure. Polymethacrylate spheres with a diameter of ca. 60 nm are prepared by emulsion polymerization and are covalently attached to the protein avidin at a ratio of 5–20 avidins per sphere. The biotin-labeled rRNA is hybridized to denatured DNA in a chromosome squash. Upon incubation with a sphere solution, some of the biotin sites become labeled with spheres because of the strong non-covalent interaction between biotin and avidin. The chromosome squash is examined in the scanning electron microscope (SEM). Polymer spheres, which are visible in the SEM, are observed to label the nucleolus, where the rRNA genes are located.Contribution number 5121 from the Department of Chemistry. 相似文献
168.
H. Esseveld Catharina Monnier-Goudzwaard H. G. van Eijk Maria G. van Soestbergen 《Antonie van Leeuwenhoek》1975,41(1):449-454
A purification method for the “CAMP” factor is described. The purified preparation obtained is a peptide with a molecular weight of about 15000. Amino acid analysis has shown that this peptide contains an appreciable amount of hydroxyproline. 相似文献
169.
170.
Peter W. Andrew Maria E. Delaney Lyndon J. Rogers Arnold J. Smith 《Phytochemistry》1975,14(4):931-935
Ferredoxin was isolated from the blue-green alga Anabaena flos-aquae. Its homogeneity was shown by conventional and SDS-polyacrylamide gel electrophoresis, and isoelectric focusing on polyacrylamide gel columns, the latter indicating a pI at ca pH 3·7. The absorption spectrum had, in the oxidized state, maxima at 462, 421, 327 and 276 nm, with a shoulder at 284 nm, a spectrum characteristic of plant-type ferredoxins. The 421 : 276 nm absorbance ratio was typically 0.49. The ferredoxin effectively mediated the photoreduction of NADP+ by barley chloroplasts depleted of native ferredoxin. The MW obtained by sedimentation-equilibrium and sedimentation velocity-diffusion coefficient studies was ca 12 000 daltons, a value somewhat higher than suggested by amino acid composition data. The ferredoxin contained 2Fe and 2S per molecule. 相似文献