Hydrodynamic and circular dichroic analysis of mammary-derived growth inhibitor (MDGI).
The mammary-derived growth inhibitor exists in solution as a monomeric molecule with a molar mass of 14,500 +/- 400 g/mol. The largest diameter and the height of the polypeptide chain were estimated to be 3.75 +/- 0.25 nm and 2.01 +/- 0.13 nm respectively. This is in good agreement with the structurally related bovine peripheral myelin P2 protein (about 70% amino acid sequence homology). CD measurements have revealed MDGI to be a protein with about 50% beta structure and less than 20% alpha helix similarly as in fatty acid-binding proteins. Removal of endogenous long-chain fatty acid by lipidex or storage in the frozen state lead to a destabilization of the active MDGI conformation which is accompanied by a loss of its activity with regard to growth inhibition of Ehrlich Ascites cells.
Behlke
J
J
Central Institute of Molecular Biology, Academy of Sciences of the German Democratic Republic, Berlin-Buch.
Mieth
M
M
Böhmer
F D
FD
Grosse
R
R
D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000473:pathology; D002352:Carrier Proteins; D002417:Cattle; D002942:Circular Dichroism; D000074026:Fatty Acid Binding Protein 3; D050556:Fatty Acid-Binding Proteins; D006131:Growth Inhibitors / Q000494:pharmacology; D006801:Humans; D010455:Peptides / Q000494:pharmacology; D011487:Protein Conformation; D012996:Solutions; D013057:Spectrum Analysis; D013329:Structure-Activity Relationship; D013552:Swine; D014407:Tumor Cells, Cultured / Q000473:pathology
D002352:Carrier Proteins; C493408:FABP3 protein, human; D000074026:Fatty Acid Binding Protein 3; D050556:Fatty Acid-Binding Proteins; D006131:Growth Inhibitors; D010455:Peptides; D012996:Solutions