Proteolytic Enzymes of Clostridium welchii
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چکیده
1. Two optically isomeric open-chain pentapeptide esters have been synthesized. These peptides have the same sequence of amino-acid residues as gramicidin S. 2. A crystalline acylpentapeptide amide has been synthesized. Thiscompound is structurally analogous to the natural antibiotic in that its constituent amino-acids are arranged in the same sequence and are of the same optical configuration as those of gramicidin S and that its only reactive group is the 8-NH2 of the ornithine residue. 3. These and other newly synthesized peptides were tested, in vitro, for antibacterial activity. 4. The bearing of the results on the question of the origin of antibiotic activity in gramicidin S is discussed.
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The Hydrolysis of Hyaluronic Acid by Bacterial Enzymes
An improved method is described for preparing the enzyme which hydrolyzes the polysaccharide acid contained in vitreous humor, umbilical cord, synovial fluid, and the mucoid phase of group A hemolytic streptococci. Preparations have been obtained from pneumococci, group A hemolytic streptococci, Clostridium welchii, and from splenic tissue, which display the same specific activity. Evidence is ...
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