Conversion of Serum Proteins into Tissue Proteins.
- 1 August 1959
- journal article
- research article
- Published by Frontiers Media SA in Experimental Biology and Medicine
- Vol. 101 (4) , 860-863
- https://doi.org/10.3181/00379727-101-25120
Abstract
Summary 1. Incorporation of S35 and C14 from injected doubly labeled rat serum albumin or globulin into the tissue proteins of rats was investigated. The ratio S35/C14 in tissue proteins varies very little during 9 days after injection of the doubly labeled serum proteins. 2. The ratio S35/C14 in tisues is approximately equal to (S35P/C14P) X (ST/SP) × Qc where the first term is the ratio of the 2 isotopes in the injected plasma protein, ST and SP the per cent of total sulfur in the analyzed tissue protein and the injected plasma protein, respectively, and Qc is approximately 1.5. 3. The increase in S35/C14 ratio (Qc > 1) indicates impoverishment of C14 relative to S35 and is attributed to utilization of C14-amino acids for other metabolic pathways. 4. In rats injected with serum albumin-S35, I131 the ratio S35/I131 increases during 9 days from 50 to 100 times. 5. Our results indicate that conversion of plasma proteins into tissue proteins involves breakdown to amino acids or very small peptide fragments. There is no indication for the transfer of large peptide fragments from plasma protein to tissue protein molecules.Keywords
This publication has 1 reference indexed in Scilit:
- Rate of elimination of homologous globulins (including antibody) from the circulationBiochemical Journal, 1954