Publications by authors named "Carla Cristina Polo"
The glycoside hydrolase family 39 (GH39) is a functionally expanding family with limited understanding about the molecular basis for substrate specificity and extremophilicity. In this work, we demonstrate the key role of the positive-subsite region in modulating substrate affinity and how the lack of a C-terminal extension impacts on oligomerization and structural stability of some GH39 members. The crystallographic and SAXS structures of a new GH39 member from the phytopathogen support the importance of an extended C-terminal to promote oligomerization as a molecular strategy to enhance thermal stability.
View Article and Find Full Text PDFThe chemical properties of materials are dependent on dynamic changes in their three-dimensional (3D) structure as well as on the reactive environment. We report an 3D imaging study of defect dynamics of a single gold nanocrystal. Our findings offer an insight into its dynamic nanostructure and unravel the formation of a nanotwin network under CO oxidation conditions.
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- Adenosine Kinase (ADK) manages adenosine levels in cells by controlling its metabolic clearance and is influenced by substrates, products, and ions like magnesium and potassium.
- New crystal structures of mouse ADK show how adenosine and ADP bind to the enzyme, revealing a model where adenosine inhibits ADK's activity.
- The binding of potassium alters the enzyme's structure, enhancing its catalytic function, and suggests that ADK plays a key role in linking potassium levels to purine metabolism.
Article Synopsis
- Metagenomics has been used to discover new enzymes, and this study focuses on a novel endoxylanase (SCXyl) found in sugarcane soil metagenome, which can help convert lignocellulosic biomass into fuels and chemicals.
- The enzyme shows high activity against xylan from beechwood at pH 6.0 and 45°C, and its crystal structure reveals a flexible active site that adapts to different substrates.
- SCXyl not only breaks down xylan polymers into xylooligosaccharides but also improves the efficiency of the saccharification process when used before commercial cellulases, making it useful for applications in the food, feed, and bioenergy industries.