Characterization of the β-glucuronidase Pn3Pase as the founding member of glycoside hydrolase family GH169.

Autor:	Wantuch PL; Department of Biochemistry & Molecular Biology, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA.; Center for Molecular Medicine, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA., Jella S; Center for Molecular Medicine, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA., Duke JA; Department of Biochemistry & Molecular Biology, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA.; Center for Molecular Medicine, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA., Mousa JJ; Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, 501 D.W. Brooks Dr Athens, Athens GA 30602, USA.; Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, 501 D.W. Brooks Dr Athens, Athens GA 30602, USA., Henrissat B; Architecture et Fonction des Macromolécules Biologiques, CNRS, Aix-Marseille University, 163 Avenue de Luminy, Parc Scientifique et Technologique de Luminy, 13288 Marseille, France.; USC1408 Architecture et Fonction des Macromolécules Biologiques, Institut National de la Recherche Agronomique, 163 Avenue de Luminy, Parc Scientifique et Technologique de Luminy, 13288 Marseille, France.; Department of Biological Sciences, King Abdulaziz University, Al Jami`ah, Jeddah, 23218, Saudi Arabia., Glushka J; Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Rd, Athens GA 30602, USA., Avci FY; Department of Biochemistry & Molecular Biology, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA.; Center for Molecular Medicine, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA.
Jazyk:	angličtina
Zdroj:	Glycobiology [Glycobiology] 2021 Apr 01; Vol. 31 (3), pp. 266-274.
DOI:	10.1093/glycob/cwaa070
Abstrakt:	Paenibacillus sp. 32352 is a soil-dwelling bacterium capable of producing an enzyme, Pn3Pase that degrades the capsular polysaccharide of Streptococcus pneumoniae serotype 3 (Pn3P). Recent reports on Pn3Pase have demonstrated its initial characterization and potential for protection against highly virulent S. pneumoniae serotype 3 infections. Initial experiments revealed this enzyme functions as an exo-β1,4-glucuronidase cleaving the β(1,4) linkage between glucuronic acid and glucose. However, the catalytic mechanism of this enzyme is still unknown. Here, we report the detailed biochemical analysis of Pn3Pase. Pn3Pase shows no significant sequence similarity to known glycoside hydrolase (GH) families, thus this novel enzyme establishes a new carbohydrate-active enzyme (CAZy) GH family. Site-directed mutagenesis studies revealed two catalytic residues along with truncation mutants defining essential domains for function. Pn3Pase and its mutants were screened for activity, substrate binding and kinetics. Additionally, nuclear magnetic resonance spectroscopy analysis revealed that Pn3Pase acts through a retaining mechanism. This study exhibits Pn3Pase activity at the structural and mechanistic level to establish the new CAZy GH family GH169 belonging to the large GH-A clan. This study will also serve toward generating Pn3Pase derivatives with optimal activity and pharmacokinetics aiding in the use of Pn3Pase as a novel therapeutic approach against type 3 S. pneumoniae infections. (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu