Asp141 and the Hydrogen-Bond Chain Asp141-Asn109-Asp33 Are Respectively Essential for GT80 Sialyltransferase Activity and Structural Stability.
Biochemistry (Mosc)
; 80(8): 1073-9, 2015 Aug.
Article
em En
| MEDLINE
| ID: mdl-26547076
ABSTRACT
Sialyltransferases are key enzymes involved in the biosynthesis of biologically and pathologically important sialic acid-containing molecules in nature. In this study, the activity of a putative sialyltransferase (Pm0160) harboring an inherent mutation D141Y in the conserved DDG motif, which has been identified in GT52 and GT80 families, was restored by reverse mutation. More interestingly, a hydrogen-bond chain was found to form between three conserved residues (Asp141, Asn109, and Asp33) of GT80 sialyltransferases based on recently determined crystal structures. Our mutagenesis experiments demonstrated that the hydrogen-bond chain connecting the general base Asp141 with Nß4, Nß1, and Nα1 plays an essential role in maintaining protein structural stability other than keeping the general base Asp141 in a productive orientation for sialic acid transfer.
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Base de dados:
MEDLINE
Assunto principal:
Sialiltransferases
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article