Use of influenza C virus for detection of 9-O-acetylated sialic acids on immobilized glycoconjugates by esterase activity.
An overlay and a solid-phase assay are presented which allow the specific detection of 9-O-acetylated sialic acids on sialoglycoconjugates immobilized on microtiter plates, nitrocellulose or separated on thin-layer chromatograms. The assay takes advantage of two different biological properties of influenza C virus, its high-affinity binding to 9-O-acetylated sialic acids and its sialate 9-O-acetylesterase that is used for detection of bound virus with fluorogenic or chromogenic substrates. Though simple and rapid, the assay is highly sensitive with a detection limit of 65 fmol 9-O-acetylated sialic acid in 9-O-acetylated ganglioside GD1a. Influenza C virus is able to bind to a wide spectrum of sialoglycoconjugates like mucins, serum glycoproteins or gangliosides containing naturally or synthetically O-acetylated sialic acids. 9-O-Acetyl-N-glycoloylneuraminic acid can also function as a high-affinity receptor determinant for influenza C virus. While the acetyl ester at the 9 position is essential for virus binding in all cases, a 4-O-acetyl group is not recognized. In addition to alpha(2.3) or alpha(2.6) bonds, 9-O-acetyl-N-acetylneuraminic acid in alpha(2.8) linkage to N-acetylneuraminic acid is also functionally active.
Zimmer
G
G
Biochemisches Institut, Christian-Albrechts-Universität, Kiel, Federal Republic of Germany.
Reuter
G
G
Schauer
R
R
D000115:Acetylesterase; D000818:Animals; D001923:Brain Chemistry; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism*; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D005732:Gangliosides / Q000737:chemistry; D006001:Glycoconjugates / Q000032:analysis*; D006168:Guinea Pigs; D006801:Humans; D009982:Gammainfluenzavirus / Q000201:enzymology / Q000378:metabolism*; D009077:Mucins / Q000737:chemistry; D051381:Rats; D011919:Rats, Inbred Strains; D012463:Saliva / Q000737:chemistry; D012794:Sialic Acids / Q000032:analysis* / Q000378:metabolism; D013363:Submandibular Gland / Q000737:chemistry
D005732:Gangliosides; D006001:Glycoconjugates; D009077:Mucins; D012794:Sialic Acids; C025676:9-O-acetyl-N-acetylneuraminic acid; D002265:Carboxylic Ester Hydrolases; D000115:Acetylesterase; C046298:sialate O-acetylesterase