3W4P

Crystal structure of PenI beta-lactamase from Burkholderia pseudomallei at pH7.5

3W4P の概要

• エントリーDOI: 10.2210/pdb3w4p/pdb
• 関連するPDBエントリー: 2ov5 3W4O 3W4Q
• 分子名称: Beta-lactamase, GLYCEROL, SULFATE ION, ... (4 entities in total)
• 機能のキーワード: beta-lactamase, hydrolase
• 由来する生物種: Burkholderia pseudomallei
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 28755.51

構造登録者

Nukaga, M.,Ohuchi, N.,Papp-Wallace, K.M.,Taracila, M.A.,Bonomo, R.A. (登録日: 2013-01-10, 公開日: 2013-05-15, 最終更新日: 2024-04-03)

主引用文献

Papp-Wallace, K.M.,Taracila, M.A.,Gatta, J.A.,Ohuchi, N.,Bonomo, R.A.,Nukaga, M.
Insights into beta-lactamases from Burkholderia species, two phylogenetically related yet distinct resistance determinants
J.Biol.Chem., 288:19090-19102, 2013

PubMed Abstract: Burkholderia cepacia complex and Burkholderia pseudomallei are opportunistic human pathogens. Resistance to β-lactams among Burkholderia spp. is attributable to expression of β-lactamases (e.g. PenA in B. cepacia complex and PenI in B. pseudomallei). Phylogenetic comparisons reveal that PenA and PenI are highly related. However, the analyses presented here reveal that PenA is an inhibitor-resistant carbapenemase, most similar to KPC-2 (the most clinically significant serine carbapenemase), whereas PenI is an extended spectrum β-lactamase. PenA hydrolyzes β-lactams with k(cat) values ranging from 0.38 ± 0.04 to 460 ± 46 s(-1) and possesses high k(cat)/k(inact) values of 2000, 1500, and 75 for β-lactamase inhibitors. PenI demonstrates the highest kcat value for cefotaxime of 9.0 ± 0.9 s(-1). Crystal structure determination of PenA and PenI reveals important differences that aid in understanding their contrasting phenotypes. Changes in the positioning of conserved catalytic residues (e.g. Lys-73, Ser-130, and Tyr-105) as well as altered anchoring and decreased occupancy of the deacylation water explain the lower k(cat) values of PenI. The crystal structure of PenA with imipenem docked into the active site suggests why this carbapenem is hydrolyzed and the important role of Arg-220, which was functionally confirmed by mutagenesis and biochemical characterization. Conversely, the conformation of Tyr-105 hindered docking of imipenem into the active site of PenI. The structural and biochemical analyses of PenA and PenI provide key insights into the hydrolytic mechanisms of β-lactamases, which can lead to the rational design of novel agents against these pathogens.

PubMed: 23658015
DOI: 10.1074/jbc.M113.458315

実験手法

X-RAY DIFFRACTION (1.05 Å)