N-glycan Utilization by Bifidobacterium Gut Symbionts Involves a Specialist beta-Mannosidase

Autor(es)

Cordeiro, Rosa Lorizolla ^{[1, 2]} ; Siqueira Pirolla, Renan Augusto ^[1] ; Persinoti, Gabriela Felix ^[1] ; Gozzo, Fabio Cesar ^[3] ; de Giuseppe, Priscila Oliveira ^[1] ; Murakami, Mario Tyago ^[1]

Afiliação do(s) autor(es)

^[1] Brazilian Ctr Res Energy & Mat CNPEM, Brazilian Bioethanol Sci & Technol Lab CTBE, BR-13083970 Campinas, SP - Brazil

^[2] Univ Estadual Campinas, Inst Biol, Grad Program Funct & Mol Biol, Campinas, SP - Brazil

^[3] Univ Estadual Campinas, Inst Chem, Dalton Mass Spectrometry Lab, Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Molecular Biology; v. 431, n. 4, p. 732-747, FEB 15 2019.
• Citações Web of Science: 0

Resumo

Bifidobacteria represent one of the first colonizers of human gut microbiota, providing to this ecosystem better health and nutrition. To maintain a mutualistic relationship, they have enzymes to degrade and use complex carbohydrates non-digestible by their hosts. To succeed in the densely populated gut environment, they evolved molecular strategies that remain poorly understood. Herein, we report a novel mechanism found in probiotic Bifidobacteria for the depolymerization of the ubiquitous 2-acetamido-2-deoxy-4-O-(beta-D-mannopyranosyl)-D-glucopyranose (Man-beta-1,4-GlcNAc), a disaccharide that composes the universal core of eukaryotic N-glycans. In contrast to Bacteroidetes, these Bifidobacteria have a specialist and strain-specific beta-mannosidase that contains three distinctive structural elements conferring high selectivity for Man-beta-1,4-GlcNAc: a lid that undergoes conformational changes upon substrate binding, a tryptophan residue swapped between the two dimeric subunits to accommodate the GlcNAc moiety, and a Rossmann fold subdomain strategically located near to the active site pocket. These key structural elements for Man-beta-1,4-GlcNAc specificity are highly conserved in Bifidobacterium species adapted to the gut of a wide range of social animals, including bee, pig, rabbit, and human. Together, our findings uncover an unprecedented molecular strategy employed by Bifidobacteria to selectively uptake carbohydrates from N-glycans in social hosts. (C) 2019 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 16/00740-2 - Bases mecanísticas da adaptação evolutiva à temperatura e especificidade de hidrolases glicosídicas pertencentes a novas subfamílias GH5
• Beneficiário: Rosa Lorizolla Cordeiro
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 15/26982-0 - Explorando novas estratégias para a despolimerização de polissacarídeos da parede celular vegetal: da estrutura, função e desenho racional de hidrolases glicosídicas às implicações biológicas e potenciais aplicações biotecnológicas
• Beneficiário: Mário Tyago Murakami
• Modalidade de apoio: Auxílio à Pesquisa - Temático