Hepatocytes mediate coenzyme A transfer to specific carbohydrate-derivatized surfaces

Freshly isolated chicken and rat hepatocytes adhere with carbohydrate specificity to surfaces derivatized with N-acetylglucosamine and galactose respectively. Previously (Brandley, B.K. and Schnaar, R.L. (1985) J. Biol. Chem. 260, 12474-12483) we reported that metabolically radiolabeled chicken hepatocytes covalently transferred phosphate radiolabel specifically to N-acetylglucosamine-derivatized surfaces. We now report that rat hepatocytes transfer phosphate radiolabel specifically to galactose-derivatized surfaces. Transferred radiolabel from both species to their appropriate carbohydrate-derivatized surface was identified as CoASH. After specific adhesion via the appropriate carbohydrate, CoASH is apparently released from cells and undergoes disulfide exchange with the cleavable immobilization linker we used to tether the sugars to the artificial surfaces. Although CoASH from lysed cells can undergo similar disulfide exchange, the data suggest that other, perhaps physiological mechanisms may be responsible for the carbohydrate-specific radiolabel transfer.