150 research outputs found
A cysteine proteinase in the penetration glands of the cercariae of Cotylurus cornutus (Trematoda, Strigeidae)
A cysteine proteinase from the penetration glands of Cotylurus cornutus cercariae was examined with histochemical and biochemical methods. The enzyme hydrolyzed gelatin, azocoll, azocasein, azoalbumin, N-blocked-l-arginine-4-methoxy-2-naphthylamide, and N-blocked-p-nitroanilide, but did not degrade elastin. The metal ion complexane ethylenediamine tetraacetate and the thiol-reducing compound dithioerythritol enhanced the proteinase activity, whereas the thiol-blocking compounds p-hydroxymercuribenzoate and N-ethylmaleimide (NEM) inhibited it. The enzyme was also sensitive to leupeptin but insensitive to soybean trypsin inhibitor. An electrophoretic separation of extract proteins from the cercariae under acidic, non-denaturing conditions and in the presence of 0.1% gelatin in a polyacrylamide gel revealed the presence of two distinct and three weak transparent bands in the gel resulting from a gelatinolytic activity at pH 6.8. The distinct bands apparently resulted from the activity of the glandular enzyme and lysosomal cathepsin B, whereas the weak ones presumably indicated these enzymes partially degraded in the course of the preparative procedure. No gelatinolysis occurred following treatment of an extract sample with 0.1 mM NEM
On-line desalting of physiologically derived fluids in conjunction with capillary isoelectric focusing-mass spectrometry
Studies of some experimental conditions for the polymerization of the continuous beds (cross-linked polyacrylamide gels) in order to improve their chromatographic properties
General Approach for Certain Quantitative Calculations for Instance of the Variance of Reversible Adsorption to the Capillary Wall in CE
What Types of Bonds Are Responsible for the Adhesion of Bacteria and Viruses to Native and Artificial Surfaces?
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