3R96

Crystal structure of Microcin C7 self immunity acetyltransferase MccE in complex with Acetyl-CoA and AMP

Summary for 3R96

• Entry DOI: 10.2210/pdb3r96/pdb
• Related: 3R95 3R9E 3R9F 3R9G
• Descriptor: MccE protein, ACETYL COENZYME *A, ADENOSINE MONOPHOSPHATE, ... (4 entities in total)
• Functional Keywords: microcin c7, acetyltransferase, self immunity, resistance, acetyl coenzyme a, transferase
• Biological source: Escherichia coli
• Total number of polymer chains: 2
• Total formula weight: 44410.17

Authors

Nair, S.K.,Agarwal, V. (deposition date: 2011-03-24, release date: 2011-04-20, Last modification date: 2024-02-21)

Primary citation

Agarwal, V.,Metlitskaya, A.,Severinov, K.,Nair, S.K.
Structural Basis for Microcin C7 Inactivation by the MccE Acetyltransferase.
J.Biol.Chem., 286:21295-21303, 2011

PubMed Abstract: The antibiotic microcin C7 (McC) acts as a bacteriocide by inhibiting aspartyl-tRNA synthetase and stalling the protein translation machinery. McC is synthesized as a heptapeptide-nucleotide conjugate, which is processed by cellular peptidases within target strains to yield the biologically active compound. As unwanted processing of intact McC can result in self-toxicity, producing strains utilize multiple mechanisms for autoimmunity against processed McC. We have shown previously that the mccE gene within the biosynthetic cluster can inactivate processed McC by acetylating the antibiotic. Here, we present the characterization of this acetylation mechanism through biochemical and structural biological studies of the MccE acetyltransferase domain (MccE(AcTase)). We have also determined five crystal structures of the MccE-acetyl-CoA complex with bound substrates, inhibitor, and reaction product. The structural data reveal an unexpected mode of substrate recognition through π-stacking interactions similar to those found in cap-binding proteins and nucleotidyltransferases. These studies provide a rationale for the observation that MccE(AcTase) can detoxify a range of aminoacylnucleotides, including those that are structurally distinct from microcin C7.

PubMed: 21507941
DOI: 10.1074/jbc.M111.226282

Experimental method

X-RAY DIFFRACTION (1.3 Å)