although this new o-specific polysaccharide consisted solely of mannose and the mannose residues were combined only through alpha-1,2 linkage , it was still composed of a repeating oligosaccharide unit , possibly a trisaccharide unit , -- -- 2 ) alpha man- ( 1 -- -- 2 ) alpha man- ( 1 -- -- 2 ) alpha man- ( 1 -- -- .
C0028959
oligosaccharide
C0041102
trisaccharide