Prenylated proteins: synthesis of geranylgeranylcysteine and identification of this thioether amino acid as a component of proteins in CHO cells.
Prenylated proteins, labeled in the isoprenoid residue by growing CHO cells in medium containing [5-3H]mevalonate, were degraded by three different proteolytic procedures, enzymatic or alkaline hydrolysis as well as hydrazinolysis. The products thus obtained were analyzed by HPLC with chemically prepared all-trans-geranylgeranylcysteine as a standard. About 10% of the radioactive products released by each lytic procedure showed the same chromatographic properties as geranylgeranylcysteine. This verifies the earlier conclusion, based on less-direct evidence, that this thioether derivative of cysteine is a component of naturally occurring proteins. The finding of this modified amino acid as a product of hydrazinolysis indicates that it is a carboxyl-terminal amino acid and that it is not carboxyl-methylated.
Epstein
W W
WW
Department of Chemistry, University of Utah, Salt Lake City 84108.
Lever
D C
DC
Rilling
H C
HC
D000818:Animals; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D006224:Cricetinae; D003412:Cricetulus; D003545:Cysteine / Q000031:analogs & derivatives* / Q000032:analysis / Q000138:chemical synthesis / Q000378:metabolism; D004224:Diterpenes / Q000032:analysis / Q000138:chemical synthesis* / Q000378:metabolism; D005260:Female; D010053:Ovary; D010446:Peptide Fragments / Q000302:isolation & purification; D011506:Proteins / Q000302:isolation & purification / Q000378:metabolism*
D004224:Diterpenes; D010446:Peptide Fragments; D011506:Proteins; C065977:geranylgeranylcysteine; D003545:Cysteine