4ORK

Crystal Structure of the Phosphotransferase Domain of the Bifunctional Aminoglycoside Resistance Enzyme AAC(6')-Ie-APH(2'')-Ia

4ORK の概要

• エントリーDOI: 10.2210/pdb4ork/pdb
• 分子名称: Bifunctional AAC/APH, GUANOSINE-5'-DIPHOSPHATE, MAGNESIUM ION, ... (4 entities in total)
• 機能のキーワード: kinase, antibiotic resistance, aminoglycosides and gtp, transferase
• 由来する生物種: Staphylococcus aureus
• 細胞内の位置: Cytoplasm: P0A0C1
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 145760.04

構造登録者

Smith, C.A.,Toth, M.,Bhattacharya, M.,Frase, H.,Vakulenko, S.B. (登録日: 2014-02-11, 公開日: 2014-07-02, 最終更新日: 2024-02-28)

主引用文献

Smith, C.A.,Toth, M.,Bhattacharya, M.,Frase, H.,Vakulenko, S.B.
Structure of the phosphotransferase domain of the bifunctional aminoglycoside-resistance enzyme AAC(6')-Ie-APH(2'')-Ia.
Acta Crystallogr.,Sect.D, 70:1561-1571, 2014

PubMed Abstract: The bifunctional acetyltransferase(6')-Ie-phosphotransferase(2'')-Ia [AAC(6')-Ie-APH(2'')-Ia] is the most important aminoglycoside-resistance enzyme in Gram-positive bacteria, conferring resistance to almost all known aminoglycoside antibiotics in clinical use. Owing to its importance, this enzyme has been the focus of intensive research since its isolation in the mid-1980s but, despite much effort, structural details of AAC(6')-Ie-APH(2'')-Ia have remained elusive. The structure of the Mg2GDP complex of the APH(2'')-Ia domain of the bifunctional enzyme has now been determined at 2.3 Å resolution. The structure of APH(2'')-Ia is reminiscent of the structures of other aminoglycoside phosphotransferases, having a two-domain architecture with the nucleotide-binding site located at the junction of the two domains. Unlike the previously characterized APH(2'')-IIa and APH(2'')-IVa enzymes, which are capable of utilizing both ATP and GTP as the phosphate donors, APH(2'')-Ia uses GTP exclusively in the phosphorylation of the aminoglycoside antibiotics, and in this regard closely resembles the GTP-dependent APH(2'')-IIIa enzyme. In APH(2'')-Ia this GTP selectivity is governed by the presence of a `gatekeeper' residue, Tyr100, the side chain of which projects into the active site and effectively blocks access to the adenine-binding template. Mutation of this tyrosine residue to a less bulky phenylalanine provides better access for ATP to the NTP-binding template and converts APH(2'')-Ia into a dual-specificity enzyme.

PubMed: 24914967
DOI: 10.1107/S1399004714005331

実験手法

X-RAY DIFFRACTION (2.3 Å)