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Updated: Jul 10, 2026

Specificity Analysis of Protein Lysine Methyltransferases Using SPOT Peptide Arrays
Published on: November 29, 2014
Differences in substrate selectivities of the SPOUT superfamily of methyltransferases
Takashi Toyooka1, Hiroyuki Hori
1Department of Materials Science and Biotechnology, Graduate School of Science and Engineering Ehime University, Bunkyo 3 Matuyama 790-8577, Japan.
Abstract:
Since the SPOUT superfamily was defined by homology between the SpoU and TrmD families [Anantharaman, V. et al., J. Mol. Microbiol. Biotechnol., 4, 71-75 (2002)], many crystal structures have been solved and numerous new homologous sequences have been found in the superfamily. Therefore, nowadays, we can consider enzyme function and/or evolution process of the SPOUT superfamily members using not only amino acid sequences but also protein structures. Recently, a bioinformatics research on SPOUT superfamily proposed existences of new member proteins [COG1756, COG1772, COG4080, and COG1901], and provided a structural and evolutionary classification of the proteins [Tkaczuk, K.L. et al., BMC Bioinformatics, 8:73 (2007)], which serves as a guide for studies on the SPOUT family in future. In this meeting, we report a new approach using a flexible protein structure alignment algorithm (FATCAT) to analyze the structures of SPOUT superfamily proteins, and discuss differences in substrate selectivities of methyltransferases in the superfamily.
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