Analysis of β-tubulin-carbendazim interaction reveals that binding site for MBC fungicides does not include residues involved in fungicide resistance

May 22, 2018

Title

Analysis of β-tubulin-carbendazim interaction reveals that binding site for MBC fungicides does not include residues involved in fungicide resistance

Author

David Vela-Corcía, Diego Romero, Antonio de Vicente, Alejandro Pérez-García

Year

2018

Journal

Scientific Reports

Abstract

Methyl benzimidazole carbamate (MBC) fungicides are fungicidal compounds that exert their biological activities by preventing cell division through the inhibition of tubulin polymerization, which is the major component of microtubules. Several mutations in the β-tubulin gene contribute to MBC resistance, the most common and significant of which occur at residues 198 and 200. Despite nearly 50 years of agricultural use, the binding site of MBCs and the precise mechanism by which those mutations affect fungicide efficacy have not been determined. The aim of this work was to clarify the mode of action and the mechanism of resistance to MBC fungicides in Podosphaera xanthii, the primary causal agent of cucurbit powdery mildew, using a combination of biochemical, biophysical and computational approaches. The results allow us to propose an MBC binding site in β-tubulin that lies close to the GTP binding site and does not include residue 198 involved in MBC resistance.

Instrument

J-815

Keywords

Circular dichroism, Secondary structure, Chemical stability, Biochemistry