A Combined Analysis of Transcriptome and Proteome Reveals the Inhibitory Mechanism of a Novel Oligosaccharide Ester against Penicillium italicum.

Linyan Feng,Xuewu Duan,Liangxiong Xu,Jinghua Xue,Taotao Li,Xiaojie Li

doi:10.3390/jof8020111

Abstract

Blue mold caused by Penicillium italicum is one of the most serious postharvest diseases of citrus fruit. The aim of this study was to investigate the inhibitory effect of a novel oligosaccharide ester, 6-O-β-L-mannopyranosyl-3-O-(2-methylbutanoyl)-4-O-(8-methyldecanoyl)-2-O-(4-methyl-hexanoyl) trehalose (MTE-1), against P. italicum. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM), along with transcriptome and proteome analysis also, were conducted to illuminate the underlying mechanism. Results showed that MTE-1 significantly inhibited P. italicum growth in vitro in a dose-dependent manner. Moreover, MTE-1 suppressed the disease development of citrus fruit inoculated with P. italicum. Furthermore, ultrastructure observation, as well as transcriptome and proteome analysis, indicated that MTE-1 treatment damaged the cell wall and plasma membrane in spores and mycelia of P. italicum. In addition, MTE-1 regulated genes or proteins involved in primary metabolism, cell-wall metabolism, and pathogenicity. These results demonstrate that MTE-1 inhibited P. italicum by damaging cell walls and membranes and disrupting normal cellular metabolism. These findings contribute to the understanding of the possible molecular action of MTE-1. Finally, MTE-1 also provides a new natural strategy for controlling diseases in postharvest fruit.

Highlights

Fungal infection causes severe economic losses and fruit-quality deterioration during storage and leads to adverse impacts on human health caused by mycotoxins [1,2]
We found that manno-pyranosyl trehalose esters (MTEs)-1 exerted high inhibitory activity against P. italicum in vitro and decreased the disease incidence of blue mold on postharvest citrus fruit during storage
Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations, along with transcriptomic and proteomic results, revealed that treatment with MTE-1 disrupted cell walls and ultrastructural membranes, which might account for the growth inhibition

Summary

Introduction

Fungal infection causes severe economic losses and fruit-quality deterioration during storage and leads to adverse impacts on human health caused by mycotoxins [1,2]. Penicillium italicum is an important postharvest pathogenic fungus that causes blue mold on citrus fruit. Due to the severe spoilage of citrus fruit and severe economic loss caused by blue mold, additional efforts are urgently required to explore safe and efficient strategies to inhibit P. italicum growth and prevent infection of harvested citrus fruit. Application of chemical fungicides is effective for controlling fungal disease, resistant fungal populations and environmental contamination, as well as human health, are increasingly attracting the concern of researchers [4]. In this regard, alternative strategies for fungicide application are imperatively required [5]

Objectives

Methods

Findings

Discussion

Conclusion