Dissecting the cosubstrate structure requirements of the Staphylococcus aureus aminoglycoside resistance enzyme ANT(4').
Aminoglycosides are important antibiotics used against a wide range of pathogens. As a mechanism of defense, bacteria have evolved enzymes able to inactivate these drugs by regio-selectively adding a variety of functionalities (acetyl, phospho, and nucelotidyl groups) to their scaffolds. The aminoglycoside nucleotidyltransferase ANT(4') is one of the most prevalent and unique modifying-enzymes. Here, by TLC, HRMS, and colorimetric assays, we demonstrate that the resistance enzyme ANT(4') from Staphylococcus aureus is highly substrate and cosubstrate promiscuous. We show that deoxy-ribonucleotide triphosphates (dNTPs) are better cosubstrates than NTPs. We demonstrate that the position of the triphosphate group (5' and not 3') on the ribose/deoxyribose ring is important for recognition by ANT(4'), and that NTPs with larger substituents at the 3'-position of the ribose ring are not cosubstrates for ANT(4'). We confirm that for all aminoglycosides tested, the respective nucleotidylated products are completely inactive. These results provide valuable insights into the development of strategies to combat the ever-growing bacterial resistance problem.
Department of Medicinal Chemistry, 210 Washtenaw Ave, University of Michigan, Ann Arbor, MI 48109-2216, USA. vrporter@umich.edu
Vanessa R
VR
Porter
Keith D
KD
Green
Olga E
OE
Zolova
Jacob L
JL
Houghton
Sylvie
S
Garneau-Tsodikova
D000617:Aminoglycosides / Q000378:metabolism* / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D024881:Drug Resistance, Bacterial; D009713:Nucleotidyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000201:enzymology*; D013379:Substrate Specificity
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C428104:Ant(4')-Ia protein, Staphylococcus aureus; D009713:Nucleotidyltransferases