Phosphoglucomutase 3 (= phosphoacetylglucosamine mutase) (PGM3)

Abstract

The sugar nucleotide precursor of uridine-diphospho-N-acetylglucosamine (UDP-GlcNAc) is essential for multiple forms of glycosylation. N-acetylglucosamine phosphate mutase (PGM3) catalyzes the conversion of GlcNAc-6-phosphate to GlcNAc-1-phosphate that is an essential step in hexosamine biosynthesis pathway (Fig. 132.1). The enzyme that has PGM3 activity was purified from pig submaxillary gland (Fernandez-Sorensen and Carlson 1971), and human cDNA was cloned (Mio et al. 2000; Li et al. 2000). The amino acid sequence of catalytic domains in human PGM3 is highly conserved in hexose phosphate mutases (Mio et al. 2000). PGM3 is an essential enzyme in UDP-GlcNAc synthesis, since Pgm3 mutant mice showed a marked reduction of UDP-GlcNAc levels (Greig et al. 2007).