Structure of the full-length Serratia marcescens acetyltransferase AAC(3)-Ia in complex with coenzyme A

Georgy Popov, Elena Evdokimova, Peter J. Stogios, Alexei Savchenko*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Acyl-coenzyme A-dependent N-acetyltransferases (AACs) catalyze the modification of aminoglycosides rendering the bacteria carrying such enzymes resistant to this class of antibiotics. Here we present the crystal structure of AAC(3)-Ia enzyme from Serratia marcescens in complex with coenzyme A determined to 1.8 Å resolution. This enzyme served as an architype for the AAC enzymes targeting the amino group at Position 3 of aminoglycoside main aminocyclitol ring. The structure of this enzyme has been previously determined only in truncated form and was interpreted as distinct from subsequently characterized AACs. The reason for the unusual arrangement of secondary structure elements of AAC(3)-Ia was not further investigated. By determining the full-length structure of AAC(3)-Ia we establish that this enzyme adopts the canonical AAC fold conserved across this family and it does not undergo through significant rearrangement of secondary structure elements upon ligand binding as was proposed previously. In addition, our results suggest that the C-terminal tail in AAC(3)-Ia monomer forms intramolecular hydrogen bonds that contributes to formation of stable dimer, representing the predominant oligomeric state for this enzyme.

Original languageEnglish
Pages (from-to)803-808
Number of pages6
JournalProtein Science
Issue number3
StatePublished - 1 Mar 2020
Externally publishedYes


  • AAC(3)-Ia
  • acetyltransferase
  • aminoglycosides
  • antibiotic
  • coenzyme A
  • resistance protein


Dive into the research topics of 'Structure of the full-length Serratia marcescens acetyltransferase AAC(3)-Ia in complex with coenzyme A'. Together they form a unique fingerprint.

Cite this