An Unusual His/Asp Dyad Operates Catalysis in Agar-Degrading Glycosidases DOI Creative Commons
Mert Sagiroglugil, Alba Nin‐Hill, E. Ficko-Blean

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(22), P. 16897 - 16904

Published: Nov. 1, 2024

Agarose motifs, found in agars present the cell walls of red algae, consist alternating units d-galactose (G) and α-3,6-anhydro-l-galactose (LA). Glycoside hydrolases from family 117 (GH117) cleave terminal α-1,3-glycosidic bonds, releasing LA units. Structural studies have suggested that these enzymes use unconventional catalytic machinery, involving a histidine (His302) as general acid rather than carboxylic residue most glycosidases. By means quantum mechanics/molecular mechanics metadynamics, we investigated reaction mechanism Phocaeicola plebeius GH117, confirming role His302. This shares proton with neighbor aspartate (Asp320), forming His/Asp dyad. Our study also reveals that, even though sugar unit at –1 subsite (LA) can adopt two conformations, 4C1 1,4B, only latter is catalytically competent, defining 1,4B → [4E]‡ (→ 4C1) conformational itinerary. may be applicable to similar dyad their active sites, such GH3 β-N-acetylglucosaminidase GH156 sialidase. These insights enhance our understanding glycosidase strategies could inform engineering for more efficient processing seaweed.

Language: Английский

Conformational Free Energy Landscape of β-Glucose in the Gas Phase and Aqueous Solution: Energetic, Structural, and Electronic Changes DOI Creative Commons
Qinghua Liao, M.A.B. Morais, Carme Rovira

et al.

ACS Omega, Journal Year: 2025, Volume and Issue: unknown

Published: May 9, 2025

Language: Английский

Citations

0
Organic precursors for tailored synthesis of sulfur- and nitrogen-doped mesoporous carbons: a molecular design approach DOI
Takashi Hamada, Hiroki Nara, Minjun Kim

et al.

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(37), P. 4914 - 4917

Published: Jan. 1, 2024

The tailor-made synthesis of heteroatom-doped mesoporous carbon through a bottom-up approach utilizing molecular design and the soft template method.

Language: Английский

Citations

0
An Unusual His/Asp Dyad Operates Catalysis in Agar-Degrading Glycosidases DOI Creative Commons
Mert Sagiroglugil, Alba Nin‐Hill, E. Ficko-Blean

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(22), P. 16897 - 16904

Published: Nov. 1, 2024

Agarose motifs, found in agars present the cell walls of red algae, consist alternating units d-galactose (G) and α-3,6-anhydro-l-galactose (LA). Glycoside hydrolases from family 117 (GH117) cleave terminal α-1,3-glycosidic bonds, releasing LA units. Structural studies have suggested that these enzymes use unconventional catalytic machinery, involving a histidine (His302) as general acid rather than carboxylic residue most glycosidases. By means quantum mechanics/molecular mechanics metadynamics, we investigated reaction mechanism Phocaeicola plebeius GH117, confirming role His302. This shares proton with neighbor aspartate (Asp320), forming His/Asp dyad. Our study also reveals that, even though sugar unit at –1 subsite (LA) can adopt two conformations, 4C1 1,4B, only latter is catalytically competent, defining 1,4B → [4E]‡ (→ 4C1) conformational itinerary. may be applicable to similar dyad their active sites, such GH3 β-N-acetylglucosaminidase GH156 sialidase. These insights enhance our understanding glycosidase strategies could inform engineering for more efficient processing seaweed.

Language: Английский

Citations

0