Table 2.

Preferred acceptor substrates and products for the human ST8Sia family.

Enzyme	Substrate	Product	Ref.
ST8Sia 1	GM3, GD1a, GT1b gangliosides	GD3, GT1a, and GQ1b gangliosides	(96, 97)
ST8Sia 2	Monosialylated N-glycans	DiSia, oligoSia, and polySia (30DP)	(45)
ST8Sia 3	Monosialylated N-glycans Keratan sulfate O-glycans	DiSia, triSia, oligoSia, and polySia (only autopolysialylation)	(13, 14, 62, 98)
ST8Sia 4	Monosialylated N-glycans Oligosialylated N-glycans Mucin type O-glycans	DiSia, oligoSia, and polySia (50DP)	(39, 46)
ST8Sia 5	GD3, GM1b, GD1a, GT1b, GQ1c	GT3, GD1c, GT1a, GQ1b, GP1c	(99, 100)
ST8Sia 6	α2,3-Sialylated core 1 O-glycans	Disia O-glycoproteins	(101, 102)

STs from the ST8 family catalyze the transfer of Siaα2,8 to different glycoprotein and glycolipid substrates.

diSia, disialic acid; oligoSia, oligosialic acid; polySia, polysialic acid; triSia, trisialic acid.