Purification of Protein AP-Toxin from Arthrinium phaeospermum Causing Blight in Bambusa pervariabilis × Dendrocalamopisis grandis and Its Metabolic Effects on Four Bamboo Varieties

Abstract

Bambusa pervariabilis × Dendrocalamopisis grandis blight is caused by a toxin produced by the fungus Arthrinium phaeospermum. In this study, a toxin fraction (P1-2-2) with an estimated molecular mass of 31 kDa was purified from a culture filtrate of this fungus by ammonium sulfate precipitation, Sephadex G-50 gel chromatography, Q Sepharose Fast Flow anion exchange resin, and Sephadex G-75 chromatography. The N-terminal amino acid sequence (i.e., H(2)N-Gln-Val-Arg-Asp-Arg-Leu-Glu-Ser-Thr) determined by Edman degradation showed homology to known serine alkaline proteases. The purified protein was named AP-toxin. Effects of the purified protein toxin on total phenol, flavonoid, total nucleic acid, DNA, RNA, soluble protein, and soluble sugar content, as well as DNase and RNase activities and disease index, were analyzed in different bamboo varieties by the impregnation method. The toxin had a significant effect on each parameter tested. In addition, a significant correlation was observed among the metabolic index, treatment time, bamboo resistance, and disease index. These data suggest that AP-toxin plays an important role in mediating the phytotoxic activities of A. phaeospermum. This study also indicates that metabolic indices could reflect the resistance indices of hybrid bamboo to blight.

Effects of fungicide seed treatments and a winter cereal rye cover crop in no till on the seedling disease complex in corn

“…Disease incidence (DI) was determined based on the percentage of seedlings in each cup or plot with visible lesions, or from which isolates of a given genus (Fusarium, Pythium or Rhizoctonia) were recovered. Disease incidence (DI) and disease severity (DS) were combined into a single disease index (DX), using the formula DX = DI × DS/5 (Li et al, 2013;Kandel et al, 2015).…”

Differential Proteomics Based on TMT and PRM Reveal the Resistance Response of Bambusa pervariabilis × Dendrocalamopisis grandis Induced by AP-Toxin

“…Purified AP-toxin was prepared by the Forest Conservation Laboratory of Sichuan Agricultural University [14,15,16] and configured as the inducer (diluted to 40 μg/mL with sterile distilled water and inactivated at 60 °C) [17].…”

“…In this study, the purified toxin of A. phaeospermum (AP-Toxin) was obtained by Li et al [14,15,16]. Through the results of a previous study, the best inducer was the purified pathogen toxin inactivated at 60 °C, and the concentration was 40 μg/mL [17].…”

Differential Proteome Analysis of Hybrid Bamboo (Bambusa pervariabilis × Dendrocalamopsis grandis) Under Fungal Stress (Arthrinium phaeospermum)

“…Bambusa pervariabilis McClure × Dendrocalamopsis grandis (Q.H.Dai & X.l.Tao ex Keng f.) Ohrnb., which is a species of hybrid bamboo with B. pervaiabilis and D. grandis as the male and female parents, has been extensively planted in southern China due to its characteristically advantageous abilities of growth and reproduction. It is often involved in the process of afforestation along rivers, which not only increases overall bamboo resources, but also conserves water and soil and improves the ecology in multiple different environments 20 , including the reinstatement of farmland and ecological forest construction along the Changjiang river basin in China 21 . However, one destructive disease, hybrid bamboo blight occurs in many provinces of China, causing the dead area of hybrid bamboo to reach 3000 hm2.…”