Reversible O-Acetyl Migration within the Sialic Acid Side Chain and Its Influence on Protein Recognition.
ACS Chem Biol
; 16(10): 1951-1960, 2021 10 15.
Article
em En
| MEDLINE
| ID: mdl-33769035
ABSTRACT
O-Acetylation is a common naturally occurring modification of carbohydrates and is especially widespread in sialic acids, a family of nine-carbon acidic monosaccharides. O-Acetyl migration within the exocyclic glycerol-like side chain of mono-O-acetylated sialic acid reported previously was from the C7- to C9-hydroxyl group with or without an 8-O-acetyl intermediate, which resulted in an equilibrium that favors the formation of the 9-O-acetyl sialic acid. Herein, we provide direct experimental evidence demonstrating that O-acetyl migration is bidirectional, and the rate of equilibration is influenced predominantly by the pH of the sample. While the O-acetyl group on sialic acids and sialoglycans is stable under mildly acidic conditions (pH < 5, the rate of O-acetyl migration is extremely low), reversible O-acetyl migration is observed readily at neutral pH and becomes more significant when the pH increases to slightly basic. Sialoglycan microarray studies showed that esterase-inactivated porcine torovirus hemagglutinin-esterase bound strongly to sialoglycans containing a more stable 9-N-acetylated sialic acid analog, but these compounds were less resistant to periodate oxidation treatment compared to their 9-O-acetyl counterparts. Together with prior studies, the results support the possible influence of sialic acid O-acetylation and O-acetyl migration to host-microbe interactions and potential application of the more stable synthetic N-acetyl mimics.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Polissacarídeos
/
Ácidos Siálicos
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Proteínas Virais de Fusão
/
Hemaglutininas Virais
Limite:
Animals
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article