brand of vitamin K-1(phytonadione);
the natural plant vitamin K that is free
of the toxicity associated with syn-
This figure illustrates the importance
of vitamin K-1 in post-translational
modification of certain glutamic acid
residues into gamma-carboxy g.acid.
The presence of gamm-carboxy res-
idues allows that protein to specific-
ally bind calcium ions more avidly.
VII, IX and X
Formed in the liver.
PROTEINS S and C
Like the classic clotting
factors, these VKDP are
formed in the liver and
then circulate to counter
-balance the clotting
Kidney cells produce at least three proteins with NEPHROCALCIN (NC), a VKDP (M.W. 14,000), being the most important. In the urine of stone-forming patients, the NC is abnormally undercarboxylated.