RESUMO
Pfam DUF1680 (PF07944) is an uncharacterized protein family conserved in many species of bacteria, actinomycetes, fungi, and plants. Previously, we cloned and characterized the hypBA2 gene as a ß-L-arabinobiosidase in Bifidobacterium longum JCM 1217. In this study, we cloned a DUF1680 family member, the hypBA1 gene, which constitutes a gene cluster with hypBA2. HypBA1 is a novel ß-L-arabinofuranosidase that liberates L-arabinose from the L-arabinofuranose (Araf)-ß1,2-Araf disaccharide. HypBA1 also transglycosylates 1-alkanols with retention of the anomeric configuration. Mutagenesis and azide rescue experiments indicated that Glu-338 is a critical residue for catalytic activity. This study provides the first characterization of a DUF1680 family member, which defines a new family of glycoside hydrolases, the glycoside hydrolase family 127.
Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Bifidobacterium/enzimologia , Glicosídeo Hidrolases/metabolismo , Aminoácidos/metabolismo , Arabinose/análogos & derivados , Arabinose/química , Arabinose/metabolismo , Proteínas de Bactérias/isolamento & purificação , Bifidobacterium/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Cromatografia em Camada Fina , Eletroforese em Gel de Poliacrilamida , Fermentação , Glicoproteínas/metabolismo , Glicosídeo Hidrolases/química , Glicosilação , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Ressonância Magnética , Modelos Biológicos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Mutantes/metabolismo , Proteínas Recombinantes/metabolismo , Análise de Sequência de Proteína , Especificidade por Substrato , TemperaturaRESUMO
Pfam DUF1680 (PF07944) is an uncharacterized protein family conserved in many species of bacteria, actinomycetes, fungi, and plants. In a previous article, we cloned and characterized the hypBA2 gene as a ß-l-arabinobiosidase in Bifidobacterium longum JCM 1217. In this study, we cloned a DUF1680 family member, the hypBA1 gene, which constitutes a gene cluster with hypBA2. HypBA1 is a novel ß-l-arabinofuranosidase that liberates l-arabinose from the l-arabinofuranose (Araf)-ß1,2-Araf disaccharide. HypBA1 also transglycosylates 1-alkanols with retention of the anomeric configuration. Mutagenesis and azide rescue experiments indicated that Glu-366 is a critical residue for catalytic activity. This report provides the first characterization of a DUF1680 family member, which defines a new family of glycoside hydrolases, the GH family 127.
