Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jan 1:534:604-609.
doi: 10.1016/j.bbrc.2020.11.033. Epub 2020 Nov 17.

Structural snapshots of CmoB in various states during wobble uridine modification of tRNA

Sehwang Jeong  1 , Jungwook Kim  2
Affiliations

Structural snapshots of CmoB in various states during wobble uridine modification of tRNA

Sehwang Jeong et al. Biochem Biophys Res Commun. .

Abstract

CmoB utilizes carboxy-S-adenosyl-l-methionine (CxSAM) to carry out unusual carboxymethyl transfer to form 5-carboxymethoxyuridine (cmo5U) of several tRNA species in Gram-negative bacteria. In this report, we present three X-ray crystal structures of CmoB from Vibrio vulnificus representing different states in the course of the reaction pathway; i.e., apo-, substrate-bound, and product-bound forms. Especially, the crystal structure of apo-CmoB unveils a novel open state of the enzyme, capturing unprecedented conformational dynamics around the substrate-binding site. The apo-structure demonstrates that the open conformation favors the release of CxSAM thus representing an inactive form. Our crystal structures of CmoB complexed with CxSAM and S-adenosyl-l-homocysteine (SAH) and combined binding assay results support the proposed mechanism underlying the cofactor selectivity, where CmoB preferentially senses negative charge around amino acid residues Lys-91, Tyr-200, and Arg-315.

Keywords: Carboxymethyl transferase; CmoB; Specificity; Structure; tRNA modification.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

Publication types

MeSH terms

Substances

LinkOut - more resources