Role of tyrosine and tryptophan residues in the structure-activity relationships of a cardiotoxin from Naja nigricollis venom.

This paper is an attempt to localize the critical area determining toxicity in a snake cardiotoxin. Toxin gamma is a single-chain polypeptide of 60 amino acids, which has been isolated from the venom of the African spitting cobra, Naja nigricollis. Three aromatic residues, namely, Trp-11, Tyr-22, and Tyr-51, have been individually modified by chemical means.

Comparative studies on soluble protein profiles and isozyme patterns of seven Trichinella isolates.

Soluble protein profiles and isozyme patterns of eight enzymes were compared for extracts of muscle stage larvae of the seven Trichinella isolates, using isoelectric focusing in polyacrylamide gel. Soluble protein profiles and isozyme patterns of four enzymes: malic enzyme, glucosephosphate isomerase, phosphoglucomutase, superoxide dismutase of them were clearly divided into four types. T.

Amino acid sequence of a less-cytotoxic basic polypeptide (LCBP) isolated from the venom of the Indian cobra (Naja naja).

A less-cytotoxic polypeptide, designated as LCBP, was isolated from the venom of Naja naja by gel filtration on Sephadex G-50 followed by CM-cellulose chromatography. The cytotoxicity toward Yoshida sarcoma cells and lethal toxicity toward mice of LCBP were both one order of magnitude lower than that of cytotoxins and that of toxin A, respectively. LCBP is a single polypeptide consisting of 61 amino acid residues with four intramolecular disulfide linkages, and the amino acid sequence is the same as that of cardiotoxin-like basic polypeptide (CLBP) isolated from the venom of Naja naja atra.

Binding of cardiotoxin analogue III from Formosan cobra venom to FL cells.

The binding equilibrium at 37 or 0 degrees C of 125I-cardiotoxin analogue III (CT III) to fetal lung (FL) cells (cultured human amnion cells) was achieved within 1 h, and the binding at 37 degrees C was irreversible. The Scatchard analysis at 37 degrees C on the binding of 125I-CT III indicated that FL cells had two types of binding sites with different association constants. The association constant and the number of high-affinity sites was 1.

Studies on the bacterial permeability of non-woven fabrics and cotton fabrics.

The permeability of cotton and non-woven fabrics to bacteria, air and water was studied. Non-woven fabrics, even when wet, showed low resistance to air, and high resistance to permeation of water and bacteria. Water-repellent cotton fabrics were resistant to permeation of water, air and bacteria, but these properties decreased on washing.

Amino acid sequence of a cardiotoxin-like basic polypeptide (CLBP) with low cytotoxic activity isolated from the venom of the Formosan cobra (Naja naja atra).

A cardiotoxin-like basic polypeptide, designated as CLBP, was isolated from the venom of Naja naja atra by gel filtration on Sephadex G-50 followed by CM-cellulose chromatography. The cytotoxicity toward Yoshida sarcoma cells and lethal toxicity toward mice of CLBP were both one-order lower than those of cardiotoxins and cobrotoxin, respectively. CLBP is a single polypeptide consisting of 61 amino acid residues with four intramolecular disulfide linkages.

[Therapeutic effect of TRQ on chronic liver injury model in rats induced by CCl4].

Rats were treated with CCl4 for 12 weeks to induce chronic liver injury. An administration of tritoqualine (TRQ) to rats was begun 3 weeks after the first CCl4 treatment, and the therapeutic effect of TRQ on this model was investigated. On the 12th week after CCl4 treatment, a marked increase in content of hydroxyproline and histamine in the liver was found.

Cytolytic activity of cytotoxin isolated from Indian cobra venom against experimental tumor cells.

Cytolytic activity of cytotoxin isolated from the venom of the Indian cobra (Naja naja) on experimental tumor cells was far stronger than that on normal cells such as peritoneal exudate cells, spleen cells, and erythrocytes of the rat. The effect on Yoshida sarcoma cells was temperature-dependent, being stronger at 37 degrees C than at 0 degrees C. Intramolecular disulfide linkages and free amino groups in the cytotoxin molecule were shown to be essential for the lytic action on the cell membrane.

Amino acid sequence of cytotoxin IIa isolated from the venom of the Indian cobra (Naja naja).

A cytotoxic basic polypeptide, designated as cytotoxin IIa, was purified to homogeneous state from the venom of the Indian cobra (Naja naja) by a combination of gel filtration on Sephadex G-50, CM-cellulose chromatography, and fast protein liquid chromatography. Cytotoxin IIa is a single polypeptide consisting of 60 amino acid residues with four intramolecular disulfide linkages. The toxin showed high cytotoxicity toward Yoshida sarcoma and ascites hepatoma cells as did cytotoxins I and II isolated from the same venom.

Studies on the mode of bacterial contamination of an operating theatre corridor floor.

Bacterial contamination of the floor of a corridor leading into an operating theatre suite was studied in relation to the site chosen for changing footwear. Recovery of bacteria showed a peak at the site of exchange of footwear, and decreased with increasing distance from the site. When the site of exchange was moved further away from the clean area, the peak of contamination moved to the new site and bacterial contamination decreased in the clean area.

Control of Late Development of Dictyostelium discoideum by Proteins Functioning at Early Stages: (D. discoideum development/mutants/temperature-shift/two-dimensional gel).

We examined two mutants of D. discoideum which are temperature-sensitive for development. At the nonpermissive temperature one mutant becomes arrested in development during the transition from the finger to the migrating slug.

Purification and characterization of antiviral substance from the bud of Syzygium aromatica.

The antiviral substance from the bud of Syzygium aromatica was purified by ether and ethyl acetate extraction and successive chromatography on Sephadex LH-60, LH-20, G-25 and Lichroprep RP-18. The purified antiviral substance was homogeneous and identified as eugeniin. Eugeniin shows antiviral activity against herpes simplex virus at a concentration of 10 microg/ml.

Purification and characterization of anti-cholinesterase factor from the venom of Naja naja atra.

The anti-cholinesterase factor from Naja naja atra venom was purified by means of successive column chromatography on Sephadex G-75, carboxymethyl-cellulose and hydroxyapatite. The purified anti-cholinesterase factor was homogeneous by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The molecular weight was estimated to be approx.