Aminoglycosides (AGs) are broad-spectrum antibiotics whose constant use and presence in growth environments has led bacteria to develop resistance mechanisms to aid in their survival. A common mechanism of resistance to AGs is their chemical modification (nucleotidylation, phosphorylation, or acetylation) by AG-modifying enzymes (AMEs). Through evolution, fusion of two AME-encoding genes has resulted in bifunctional enzymes with broader spectrum of activity. Serratia marcescens, a human enteropathogen, contains such a bifunctional enzyme, ANT(3″)-Ii/AAC(6′)-IId. To gain insight into the role, effect, and importance of the union of ANT(3″)-Ii and AAC(6′)-IId in this bifunctional enzyme, we separated the two domains and compared their activity to that of the full-length enzyme. We performed a thorough comparison of the substrate and cosubstrate profiles as well as kinetic characterization of the bifunctional ANT(3″)-Ii/AAC(6′)-IId and its individually expressed components.
|Number of pages||7|
|State||Published - Jun 2013|
Bibliographical noteFunding Information:
This work was supported by a grant from the Firland Foundation (S.G.-T.), a BSF grant 2008017 (S.G.-T.), and a National Institute of Health (NIH) grant AI090048 (S.G.-T.) We thank Vanessa Porter for cloning and preliminary experimental work. We thank Dr. Paul H. Roy for the Serratia marcescens genomic DNA and Dr. Tapan Biswas for the Int-pET19b-pps vector. We thank Oleg V. Tsodikov for critical reading and insightful comments on the manuscript.
- Aminoglycoside antibiotics
- Bacterial resistance
- Bifunctional enzyme
ASJC Scopus subject areas