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R L Cate

Publications and source records attributed to R L Cate.

47 records · Page 3Linked to original sources

Purification of three arginine esterases from the venom of the Western Diamondback rattlesnake (Crotalus atrox).

Three acidic arginine esterases have been isolated from the venom of the Western Diamondback rattlesnake (Crotalus atrox). These components demonstrated marked differences in ionic characteristics, as noted by KCl gradient elution from a DEAE-Sephadex A-50 column. Molecular weights, as determined from gel permeation chromatography, were estimated at 25,100 (fraction D), 24,000 (B); and 22,900 (F) for the three separate enzymes. The two larger enzymes (B and D) exhibited similar activities toward the synthetic substrates alpha-N-benzoyl-L-arginine ethyl ester and alpha-N-benzoyl-DL-arginine-p-nitroanilide. Hydrolysis rates were similar to commercial trypsin preparations. Fraction F exhibited a markedly lower activity as an arginine esterase and negligible activity as an arginine amidase. Arginine esterase activity was evident for all three enzymes in the presence of ethylenediamine tetra-acetic acid.

Animals↗

Cloning and expression of human lipocortin, a phospholipase A2 inhibitor with potential anti-inflammatory activity.

The anti-inflammatory action of glucocorticoids has been attributed to the induction of a group of phospholipase A2 inhibitory proteins, collectively called lipocortin. These proteins are thought to control the biosynthesis of the potent mediators of inflammation, prostaglandins and leukotrienes, by inhibiting the release of their common precursor, arachidonic acid, a process that requires phospholipase A2 hydrolysis of phospholipids. Lipocortin-like proteins have been isolated from various cell types, including monocytes, neutrophils and renal medullary cell preparations. The predominant active form is a protein with an apparent relative molecular mass (Mr) of 40,000 (40K). These partially purified preparations of lipocortin mimic the effect of steroids, and mediate anti-inflammatory activity in various in vivo model systems. Using amino-acid sequence information obtained from purified rat lipocortin, we have now cloned human lipocortin complementary DNA and expressed the gene in Escherichia coli. Our studies confirm that lipocortin is a potent inhibitor of phospholipase A2 activity.

Amino Acid Sequence↗