Functional and biosynthetic aspects of sialic acid diversity.
Sialic acids comprise a large family of N- and O-substituted neuraminic acid derivatives as components of glycoconjugates. N-Glycolylneuraminic acid is formed from N-acetylneuraminic acid by the action of the CMP-N-acetylneuraminic acid hydroxylase studied in various animals. O-Methylated sialic acids originate from the action of S-adenosylmethionine-8-O-methyltransferase studied in starfish. Sialic acids are O-acetylated at diverse positions by the action of acetyl-CoA-4-O- and -7-O-acetyltransferases found in various animals and, leading to the O-acetylation of sialic acid glycerol side chain, also in man. Some properties of these enzymes are described and biological implications discussed.
Schauer
R
R
Biochemisches Institut, Christian-Albrechts-Universität zu Kiel, Germany. schauer@biochem.uni-kiel.de
de Freese
A
A
Gollub
M
M
Iwersen
M
M
Kelm
S
S
Reuter
G
G
Schlenzka
W
W
Vandamme-Feldhaus
V
V
Shaw
L
L
D000101:Acetyl-CoA C-Acetyltransferase / Q000378:metabolism; D000107:Acetylation; D000818:Animals; D006801:Humans; D008745:Methylation; D008780:Methyltransferases / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000378:metabolism; D015394:Molecular Structure; D012794:Sialic Acids / Q000096:biosynthesis* / Q000737:chemistry*; D013215:Starfish / Q000201:enzymology
D012794:Sialic Acids; D006899:Mixed Function Oxygenases; C074383:CMPacetylneuraminate monooxygenase; D008780:Methyltransferases; D000101:Acetyl-CoA C-Acetyltransferase