Abstract
1. Fibrinolysin-activated lysin factor and chloroform-activated serum protease of serum and plasma are one and the same enzyme, differing only in their mode of activation. 2. The enzyme as it normally occurs in serum or plasma is not inactive because of combination with serum inhibitor. It is present as an inactive precursor or zymogen and may be activated from this state by streptococcal fibrinolysin. 3. The activation of serum protease by streptococcal fibrinolysin is a catalytic reaction, analogous to the kinase activation of trypsinogen by enterokinase. Treatment of serum or plasma with chloroform apparently results in removal of serum inhibitor which may allow autocatalytic activation of the serum protease. 4. The serum enzyme differs from trypsin in its pH of optimum activity, in its reactions with specific protease inhibitors, and in its action on casein. 5. A revised nomenclature for the serum enzyme system is suggested which more accurately describes its properties than the terms in current use.
Full Text
The Full Text of this article is available as a PDF (1.3 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Hedin S. G. On the antitryptic action of serum-albumin. J Physiol. 1905 Jul 13;32(5-6):390–394. doi: 10.1113/jphysiol.1905.sp001091. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mirsky I. A. INHIBITION OF beta HEMOLYTIC STREPTOCOCCI FIBRINOLYSIN BY TRYPSIN INHIBITOR (ANTIPROTEASE). Science. 1944 Sep 1;100(2592):198–200. doi: 10.1126/science.100.2592.198. [DOI] [PubMed] [Google Scholar]
- Opie E. L., Barker B. I. ENZYMES OF TUBERCULOUS TISSUE. J Exp Med. 1908 Sep 5;10(5):645–665. doi: 10.1084/jem.10.5.645. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Opie E. L., Barker B. I. LEUCOPROTEASE AND ANTI-LEUCOPROTEASE OF MAMMALS AND OF BIRDS. J Exp Med. 1907 Mar 14;9(2):207–221. doi: 10.1084/jem.9.2.207. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tagnon H. J., Davidson C. S., Taylor F. H. THE COAGULATION DEFECT IN HEMOPHILIA: A COMPARISON OF THE PROTEOLYTIC ACTIVITY OF CHLOROFORM PREPARATIONS OF HEMOPHILIC AND NORMAL HUMAN PLASMA. J Clin Invest. 1943 Jan;22(1):127–129. doi: 10.1172/JCI101363. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yamakawa S. THE AUTODIGESTION OF NORMAL SERUM THROUGH THE ACTION OF CERTAIN CHEMICAL AGENTS. II. J Exp Med. 1918 Jun 1;27(6):711–724. doi: 10.1084/jem.27.6.711. [DOI] [PMC free article] [PubMed] [Google Scholar]