Does Acinetobacter calcoaceticus glucose dehydrogenase produce self-damaging H2O2 ? - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Bioscience Reports Année : 2024

Does Acinetobacter calcoaceticus glucose dehydrogenase produce self-damaging H2O2 ?

Résumé

The soluble glucose dehydrogenase (sGDH) from Acinetobacter calcoaceticus has been widely studied and is used, in biosensors, to detect the presence of glucose, taking advantage of its high turnover and insensitivity to molecular oxygen. This approach, however, presents two drawbacks: the enzyme has broad substrate specificity (leading to imprecise blood glucose measurements) and shows instability over time (inferior to other oxidizing glucose enzymes). We report the characterization of two sGDH mutants: the single mutant Y343F and the double mutant D143E/Y343F. The mutants present enzyme selectivity and specificity of 1.2 (Y343F) and 5.7 (D143E/Y343F) times higher for glucose compared with that of the wild-type. Crystallographic experiments, designed to characterize these mutants, surprisingly revealed that the prosthetic group PQQ (pyrroloquinoline quinone), essential for the enzymatic activity, is in a cleaved form for both wild-type and mutant structures. We provide evidence suggesting that the sGDH produces H2O2, the level of production depending on the mutation. In addition, spectroscopic experiments allowed us to follow the self-degradation of the prosthetic group and the disappearance of sGDH's glucose oxidation activity. These studies suggest that the enzyme is sensitive to its self-production of H2O2. We show that the premature aging of sGDH can be slowed down by adding catalase to consume the H2O2 produced, allowing the design of a more stable biosensor over time. Our research opens questions about the mechanism of H2O2 production and the physiological role of this activity by sGDH.
Fichier principal
Vignette du fichier
bsr-2024-0102.pdf (3.32 Mo) Télécharger le fichier
Origine Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-04606288 , version 1 (10-06-2024)

Identifiants

Citer

Victoria Lublin, Brice Kauffmann, Sylvain Engilberge, Fabien Durola, Sébastien Gounel, et al.. Does Acinetobacter calcoaceticus glucose dehydrogenase produce self-damaging H2O2 ?. Bioscience Reports, 2024, 44 (5), pp.BSR20240102. ⟨10.1042/BSR20240102⟩. ⟨hal-04606288⟩
13 Consultations
3 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More