Alpha-1,4-Galactosyltransferase (a4GALT)

Lactosylceramide 4-alpha-galactosyltransferase is an enzyme catalyzes the transfer of galactose to lactosylceramide to form globotriaosylceramide, which has been identified as the P(k) antigen of the P blood group system. The encoded protein, which is a type II membrane protein found in the Golgi, is also required for the synthesis of the bacterial verotoxins receptor.

The A4GALT gene encodes alpha-1,4-galactosyltransferase, an enzyme that transfers a galactose to the alpha-1,4 position of lactosylceramide to form globotriaosylceramide (GB3), also known as CD77. This glycolipid has been characterized on red blood cells as the P(k) antigen of the P blood group system.