Vitamin K-dependent carboxylase: the carboxylation of exogenous substrates in different systems

Marian A G de Boer-van den Berg, Magda M W Ulrich, H. Coenraad Hemker, Berry A M Soute, Cees Vermeer*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Two types of solid-phase carboxylase, SPC-II and SPC-X, have been prepared from the livers of warfarin-treated cows. Their enzymatic activities were compared with substrate-free carboxylase in microsomes from normal cows and substrate-bound carboxylase in microsomes from warfarin-treated cows. A number of exogenous substrates for carboxylase have been purified and tested. We found that large substrates, such as descarboxyprothrombin, are carboxylated only by substrate-free carboxylase and not by the substrate-bound enzyme. No differences in apparent Km values between solid-phase carboxylases II and X were observed.

Original languageEnglish
Pages (from-to)94-98
Number of pages5
JournalBiochimica et Biophysica Acta (BBA)/Protein Structure and Molecular
Issue number1
Publication statusPublished - 20 Sep 1985

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