RimL from Salmonella typhimurium

A novel dimeric structure of the RimL Na-acetyltransferase from Salmonella typhimurium. Journal of Biological Chemistry (2005) 280(23):22108-14   Principle Investigator: John Blanchard Research: Matt Vetting Collaborators: de Carvalho LP Steven Roderick PDB DATABASE IDENTIFIERS 1S7F, 1S7K, 1S7L, 1S7N

---

RimL is responsible for converting the prokaryotic ribosomal protein from L12 to L7 by acetylation of its N-terminal amino group. We demonstrate that purified RimL is capable of posttranslationally acetylating L12, exhibiting a V(max) of 21 min(-1). We have also determined the apostructure of RimL from Salmonella typhimurium and its complex with coenzyme A, revealing a homodimeric oligomer with structural similarity to other Gcn5-related N-acetyltransferase superfamily members. A large central trough located at the dimer interface provides sufficient room to bind both L12 N-terminal helices. Structural and biochemical analysis indicates that RimL proceeds by single-step transfer rather than a covalent-enzyme intermediate. This is the first structure of a Gcn5-related N-acetyltransferase family member with demonstrated activity toward a protein Na-amino group and is a first step toward understanding the molecular basis for Na-acetylation and its function in cellular regulation.