Pyocyanase

PYOCYANASE (and pyoclastin), obtained by Emmerich and Löw (1899), is a product of cultures of the blue pus bacterium (Bacillus pyocyaneus) possessing the ability to destroy bacteria. Bouchard, and immediately following him other researchers, established that the blue pus bacteria and their products can prevent the growth and reproduction of anthrax bacteria not only in test tubes but also in the animal organism. To study the mechanism of this antagonism, Emmerich and Löw used concentrated, filtered broth cultures of Bacillus pyocyaneus killed with chloroform. They found that such a preparation liquefies gelatin, dissolves fibrin, casein, coagulated serum, and egg white. In addition, it kills and partially dissolves large quantities of various bacteria, including pathogenic ones—anthrax, diphtheria, dysentery, staphylococci, streptococci, pneumococci, and gonococci. They named their preparation pyocyanase, considering it an enzyme. However, pyocyanase is resistant to boiling, and Eguchi even noted that half an hour of heating pyocyanase to 100° increases its bactericidal capacity. Furthermore, Raubitschek and Russ, as well as Eguchi, found that lipoid solvents extract the active substance from pyocyanase. Pyocyanase quickly entered medical practice. It began to be used primarily in diphtheria for dissolving membranes and bacilli; particularly good results were obtained in abscesses, phlegmons, and leg ulcers. Pyocyanase seemed harmless to tissues and favorably influenced the cleansing of wounds. It was also used for treating conjunctival catarrh, stomatitis, gingivitis, alveolar pyorrhea, as well as laryngitis and meningitis. Pyocyanase was also used for progressive paralysis and tabes dorsalis. At the present time, the use of pyocyanase has been almost abandoned due to the undoubted toxicity of the blue pus bacterial products, despite its undoubted bactericidal properties (which are, however, denied by some scientists). There are indications that filtrates of young cultures enhance the poisonous action of diphtheria toxin, playing the role of aggressins (see). It must also be kept in mind that blue pus bacteria release strong toxins, so their parenteral administration is not indifferent to the organism. Pyocyanase belongs to lysins, i.e., bacterial products that dissolve bacteria themselves. The mode of its action on bacteria cannot yet be considered elucidated. Emmerich and Löw considered it an enzyme that decomposes proteins or nucleins, i.e., triptase or nuclease. They were not disturbed by the indestructibility of pyocyanase by boiling, since heat-resistant enzymes exist. Raubitschek and Russ found that the active principle of pyocyanase can be extracted with alcohol, benzene, acetone, ether, and chloroform, and classified it among lipoids. Pane isolated from pyocyanase cultures with ether a substance bactericidal for anthrax bacteria. Gamaleya and Shvetsova developed a method for purifying cultures of the blue pus bacillus from toxic substances while preserving their bacteriological action. This method consists in acidification, precipitation with ammonium sulfate, and evaporation of cultures, after which the residue is extracted with alcohol, into which the active substance passes. It has the reactions of ptomaines and is named pyoclastin. It is non-toxic and was used by Shcheglova for the treatment of gonorrhea. Autolytic agents, analogous to pyocyanase and pyoclastin, are present in the cultures of other bacteria and have received the general name of clastins.