KARL MEYER 



whclhcr the action is cliic to the liyaluronidase contained in the prepa- 

 rations. The relationship between streptococcus infection and rheu- 

 matic fever clearly deserves an intensive study in which hyaluronic 

 acid-hyaluronidase production and liyaluronidase inhibition cannot 

 be overlooked. 



In this essay, a few mucopolysaccharides and mucolytic enzymes 

 have been dealt with, and an attempt has been made to show some of 

 the interrelationship of these entities mainly with bacteriological, but 

 also with some physiological and medical, problems. Thus, in lyso- 

 zyme and its substrate, one is concerned not only with preparative 

 chemistry, but with various problems of bacteriological variation, of 

 immunology, of virus research, and of nutrition. A study of hyaluroni- 

 dase involves many bacteriological problems, the physiology of tissue 

 permeability and fertilization, and the fields of pathology and medi- 

 cine. The study of gastric mucin has led to the problem of blood 

 groups and is intimately connected with various tissue and bacterial 

 antigens. The finding in pneumococcal extracts of an enzyme which 

 depolymerizes the acid mucopolysaccharide of submaxillary gland 

 may suggest the presence of similar enzymes in other microorganisms, 

 especially of the upper respiratory tract. 



Although other mucopolysaccharides occurring in the animal 

 body and their specific enzymes have not been discussed in this essay, 

 some of these systems are not less important, as, for example, 

 chondroitin sulfuric acid, heparin, and the carbohydrate matrix of 

 amyloid tissue. But because knowledge of the enzyme systems which 

 hydrolyze these substances is too meager, they may only be mentioned 

 at this point. It seems to the author that these and other systems de- 

 serve greater attention by the biochemist than they have hitherto 

 received. 



Addendum 



Recently a new and highly accurate method for the estimation of lysozyme 

 was developed in this laboratory. In this method the depolymerization of the 

 mucopolysaccharide isolated from M. lysodeikticus is measured viscometrically. 

 Furthermore, lysozymes, partly in very high concentration, were found in the fresh 

 and dried latex of some species of Ficus, in Euphorbia, and in papain. The Ficus 

 lysozyme is chemically distinct from that of egg white. Its potency is significantly 

 higher than the crystalline lysozyme of egg white. 



288 



