Requires Mg2+. Involved in biosynthesis of legionaminic acid, a nonulosonate derivative that is incorporated by some bacteria into assorted virulence-associated cell surface glycoconjugates. The initial product formed by the enzyme from Legionella pneumophila, which incorporates legionaminic acid into the O-antigen moiety of its lipopolysaccharide, is 2,4-diacetamido-2,4,6-trideoxy-alpha-D-mannopyranose, which rapidly mutarotates to a mixture of anomers [1]. The enzyme from Campylobacter jejuni, which incorporates legionaminic acid into flagellin, prefers GDP-N,N'-diacetylbacillosamine [2].
