title: Beta-lactamase inhibitors derived from single-domain antibody fragments elicited in the camelidae.
abstract: Small, soluble single-domain fragments derived from the unique variable region of dromedary heavy-chain antibodies (VHHs) against enzymes are known to be potent inhibitors. The immunization of dromedaries with the TEM-1 and BcII beta-lactamases has lead to the isolation of such single-domain antibody fragments specifically recognizing and inhibiting those beta-lactamases. Two VHHs were isolated that inhibit TEM-1 and one BcII inhibiting VHH was identified. All inhibitory VHHs were tight-binding inhibitors. The 50% inhibitory concentrations were determined for all inhibitors and they were all in the same range as the enzyme concentration used in the assay. Addition of the VHHs to the TEM-1 beta-lactamase, expressed on the surface of bacteria, leads to a higher ampicillin sensitivity of the bacteria. This innovative strategy could generate multiple potent inhibitors for all types of beta-lactamases.
authors.affiliation: Department of Ultrastructure, Vrije Universiteit Brussel, Pardenstraat 65, B-1640 St. Genesius Rode, Belgium. kconrath@vub.ac.be
authors.forename: K E
authors.initials: KE
authors.lastname: Conrath
authors.forename: M
authors.initials: M
authors.lastname: Lauwereys
authors.forename: M
authors.initials: M
authors.lastname: Galleni
authors.forename: A
authors.initials: A
authors.lastname: Matagne
authors.forename: J M
authors.initials: JM
authors.lastname: Frère
authors.forename: J
authors.initials: J
authors.lastname: Kinne
authors.forename: L
authors.initials: L
authors.lastname: Wyns
authors.forename: S
authors.initials: S
authors.lastname: Muyldermans
mesh_terms: D000595:Amino Acid Sequence; D000667:Ampicillin / Q000494:pharmacology; D000818:Animals; D000918:Antibody Specificity; D001426:Bacterial Proteins / Q000494:pharmacology*; D002162:Camelus / Q000276:immunology*; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology; D007128:Immunoglobulin Fragments / Q000302:isolation & purification / Q000494:pharmacology*; D008297:Male; D008969:Molecular Sequence Data; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000276:immunology
chemical_list: D001426:Bacterial Proteins; D007128:Immunoglobulin Fragments; D010406:Penicillins; D065093:beta-Lactamase Inhibitors; C065596:beta-lactamase-inhibitor protein, Streptomyces; C055966:immunoglobulin Fv; D000667:Ampicillin; D001618:beta-Lactamases