Abstract
Methylamine reacts with the plasma protease inhibitor, alpha 2-macroglobulin, to form an irreversible, covalent modification. Quantitation of the reaction indicates 3.9 +/- (SD) 0.4 reactive sites per native tetrameric protein (Mr = 725,000) or one site per subunit. The reaction is selective and specific in that only 1 or 2 labeled peptides are observed on radioautography of peptide maps derived from [14C]methylamine-treated alpha 2-macroglobulin. A single chymotryptic peptide was isolated in 56% overall yield from the labeled protein. The peptide sequence by Edman degradation was found to be Gly-Cys-Gly-Glu-X-Asn-Met-(Val, Leu), in which X was the only radiolabeled phenylthiohydantoin derivative. Amino acid analysis and mass spectral analysis of the derivative suggests that X is gamma-glutamylmethylamide. Because glutamic acid and glutamine residues do not normally react with alkylamines, this work presents presumptive evidence for an alternative activated center in selected proteins.
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Selected References
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- DALMASSO A. P., MUELLER-EBERHARD H. J. INTERACTION OF AUTOLOGOUS COMPLEMENT WITH RED CELLS IN THE ABSENCE OF ANTIBODY. Proc Soc Exp Biol Med. 1964 Dec;117:643–650. doi: 10.3181/00379727-117-29658. [DOI] [PubMed] [Google Scholar]
- Folk J. E., Chung S. I. Molecular and catalytic properties of transglutaminases. Adv Enzymol Relat Areas Mol Biol. 1973;38:109–191. doi: 10.1002/9780470122839.ch3. [DOI] [PubMed] [Google Scholar]
- Granelli-Piperno A., Reich E. A study of proteases and protease-inhibitor complexes in biological fluids. J Exp Med. 1978 Jul 1;148(1):223–234. doi: 10.1084/jem.148.1.223. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hagenmaier H., Ebbighausen W., Nicholson G., Vötsch W. Massenspektrometrische Identifizierung der Phenylthiohydantoin-Derivate von Aminosäuren. Z Naturforsch B. 1970 Jul;25(7):681–689. doi: 10.1515/znb-1970-0705. [DOI] [PubMed] [Google Scholar]
- Jones J. M., Creeth J. M., Kekwick R. A. Thio reduction of human 2 -macroglobulin. The subunit structure. Biochem J. 1972 Mar;127(1):187–197. doi: 10.1042/bj1270187. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lundell D. J., Howard J. B. Isolation and partial characterization of two different subunits from the molybdenum-iron protein of Azotobacter vinelandii nitrogenase. J Biol Chem. 1978 May 25;253(10):3422–3426. [PubMed] [Google Scholar]
- Mendez E., Lai C. Y. Regeneration of amino acids from thiazolinones formed in the Edman degradation. Anal Biochem. 1975 Sep;68(1):47–53. doi: 10.1016/0003-2697(75)90677-6. [DOI] [PubMed] [Google Scholar]
- Müller-Eberhard H. J. Complement. Annu Rev Biochem. 1975;44:697–724. doi: 10.1146/annurev.bi.44.070175.003405. [DOI] [PubMed] [Google Scholar]
- Nagasawa S., Han B. H., Sugihara H., Suzuki T. Studies on alpha 2-macroglobulin in bovine plasma. II. Interaction of alpha2-macroglobulin and trypsin. J Biochem. 1970 Jun;67(6):821–832. doi: 10.1093/oxfordjournals.jbchem.a129314. [DOI] [PubMed] [Google Scholar]
- Nelsestuen G. L., Zytkovicz T. H., Howard J. B. The mode of action of vitamin K. Identification of gamma-carboxyglutamic acid as a component of prothrombin. J Biol Chem. 1974 Oct 10;249(19):6347–6350. [PubMed] [Google Scholar]
- PILLEMER L., RATNOFF O. D., BLUM L., LEPOW I. H. The inactivation of complement and its components by plasmin. J Exp Med. 1953 Apr;97(4):573–589. doi: 10.1084/jem.97.4.573. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pochon F., Amand B., Lavalette D., Bieth J. Rotational relaxation of free and protease-bound alpha2-macroglobulin. J Biol Chem. 1978 Oct 25;253(20):7496–7499. [PubMed] [Google Scholar]
- RATNOFF O. D., LEPOW I. H., PILLEMER L. The multiplicity of plasmin inhibitors in human serum, demonstrated by the effect of primary amino compounds. Bull Johns Hopkins Hosp. 1954 Apr;94(4):169–179. [PubMed] [Google Scholar]
- Steinbuch M., Pejaudier L., Quentin M., Martin V. Molecular alteration of alpha-2-macroglobulin by aliphatic amines. Biochim Biophys Acta. 1968 Jan 22;154(1):228–231. doi: 10.1016/0005-2795(68)90277-8. [DOI] [PubMed] [Google Scholar]
- Swenson R. P., Howard J. B. Structural characterization of human alpha2-macroglobulin subunits. J Biol Chem. 1979 Jun 10;254(11):4452–4456. [PubMed] [Google Scholar]