Structural insights into substrate selectivity of ribosomal RNA methyltransferase RlmCD

Yiyang Jiang; Fudong Li; Jihui Wu; Yunyu Shi; Qingguo Gong

doi:10.1371/journal.pone.0185226

Structural insights into substrate selectivity of ribosomal RNA methyltransferase RlmCD

PLoS One. 2017 Sep 26;12(9):e0185226. doi: 10.1371/journal.pone.0185226. eCollection 2017.

Authors

Yiyang Jiang¹, Fudong Li¹, Jihui Wu¹, Yunyu Shi¹, Qingguo Gong¹

Affiliation

¹ Hefei National Laboratory For Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China.

Abstract

RlmCD has recently been identified as the S-adenosyl methionine (SAM)-dependent methyltransferase responsible for the formation of m5U at U747 and U1939 of 23S ribosomal RNA in Streptococcus pneumoniae. In this research, we determine the high-resolution crystal structures of apo-form RlmCD and its complex with SAH. Using an in-vitro methyltransferase assay, we reveal the crucial residues for its catalytic functions. Furthermore, structural comparison between RlmCD and its structural homologue RumA, which only catalyzes the m5U1939 in Escherichia coli, implicates that a unique long linker in the central domain of RlmCD is the key factor in determining its substrate selectivity. Its significance in the enzyme activity of RlmCD is further confirmed by in-vitro methyltransferase assay.

MeSH terms

Catalysis
Methyltransferases / metabolism*
RNA, Ribosomal / metabolism*
Substrate Specificity

Substances

RNA, Ribosomal
Methyltransferases

Grants and funding

This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences [XDB08010101 and XDB08030302]; Chinese National Natural Science Foundation [31270782, 91540103, 31770805 and 31330018]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.