6VNU

X-ray Crystal Structure of Ruthenocenyl-7-Aminocephalosporanic Acid Covalent Acyl-Enzyme Complex with CTX-M-14 E166A Beta-Lactamase

6VNU の概要

• エントリーDOI: 10.2210/pdb6vnu/pdb
• 分子名称: Beta-lactamase, ruthenocene, [(1,2,3,4,5-eta)-1-(4-{[carboxy(4-carboxy-5-methylidene-5,6-dihydro-2H-1,3-thiazin-2-yl)methyl]amino}-4-oxobutanoyl)cyclopentadienyl][(1,2,3,4,5-eta)-cyclopentadienyl]ruthenium, ... (5 entities in total)
• 機能のキーワード: organometallic, ctx-m-14, hydrolase
• 由来する生物種: Escherichia coli
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 57725.95

構造登録者

Lewandowski, E.M.,Jacobs, L.M.C.,Chen, Y. (登録日: 2020-01-29, 公開日: 2020-04-01, 最終更新日: 2024-11-06)

主引用文献

Lewandowski, E.M.,Szczupak, L.,Kowalczyk, A.,Mendoza, G.,Arruebo, M.,Jacobs, L.M.C.,Staczek, P.,Chen, Y.,Kowalski, K.
Metallocenyl 7-ACA Conjugates: Antibacterial Activity Studies and Atomic-Resolution X-ray Crystal Structure with CTX-M beta-Lactamase.
Chembiochem, 21:2187-2195, 2020

PubMed Abstract: The conjugation of organometallic groups to current β-lactam antibiotics is a field of increasing study due to the ability of certain organometallic groups to enhance the antibiotic potency of these drugs. Herein, we report the antibacterial properties of two metallocenyl (ferrocenyl and ruthenocenyl) 7-aminocephalosporanic acid (7-ACA) antibiotic conjugates. Continuing a trend we found in our previous studies, the ruthenocenyl conjugate showed greater antibacterial activity than its ferrocenyl counterpart. Compared with the previously published 7-aminodesacetoxycephalosporanic acid (7-ADCA) conjugates, the 3-acetyloxymethyl group significantly improved the compounds' activity. Furthermore, the Rc-7-ACA compound was more active against clinical Staphylococcus aureus isolates than the ampicillin reference. Noticeably, neither of the two new compounds showed an undesirable toxic effect in HeLa and L929 cells at the concentrations at which they displayed strong antibacterial effects. The antibacterial activity of the two metallocenyl 7-ACA derivatives was further confirmed by scanning electron microscopy (SEM). SEM micrographs showed that bacteria treated with metallocenyl 7-ACA derivatives feature cell wall damage and morphology changes. Using a CTX-M-14 β-lactamase competition assay based on nitrocefin hydrolysis, we showed that the Rc-7-ACA bound more favorably to CTX-M-14 than its ferrocenyl counterpart, again confirming the superiority of the ruthenocenyl moiety over the ferrocenyl one in interacting with proteins. We also report a 1.47 Å resolution crystal structure of Rc-7-ACA in complex with the CTX-M-14 E166A mutant, an enzyme sharing a similar active site configuration with penicillin-binding proteins, the molecular target of β-lactam antibiotics. These results strengthen the case for the antibacterial utility of the Rc and Fc groups.

PubMed: 32182393
DOI: 10.1002/cbic.202000054

実験手法

X-RAY DIFFRACTION (1.47 Å)