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Elucidating β-1,3-Glucanase and Peroxidase Physicochemical Properties of Wheat Cell Wall Defense Mechanism Against Diuraphis noxia Infestation
Published on: July 26, 2024
Molecular and biochemical characterization of Ambler class A extended-spectrum beta-lactamase CGA-1 from
Samuel Bellais1, Thierry Naas, Patrice Nordmann
1Service de Bactériologie-Virologie, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine Paris-Sud, 94275 Le Kremlin-Bicêtre Cedex, France.
Abstract:
Antibiotic susceptibility testing by disk diffusion of a Chryseobacterium gleum isolate, strain CIP 103039, showed a typical synergy image between clavulanic acid and expanded-spectrum cephalosporins. Shotgun cloning gave a recombinant plasmid in Escherichia coli that produced a beta-lactamase, CGA-1, with a pI value of 8.9 that conferred resistance to most penicillins (except ureidopenicillins) and narrow-spectrum cephalosporins and an intermediate susceptibility to expanded-spectrum cephalosporins and aztreonam. The CGA-1 amino acid sequence shared only 60% amino acid identity with CME-1 and CME-2 from Chryseobacterium meningosepticum, the most closely related beta-lactamases. CGA-1 was very likely chromosome encoded. It is a novel member of the PER subgroup of Ambler class A beta-lactamases (Bush functional group 2be).

