Characterization and antifungal activity of a plant peptide expressed in the interaction between Capsicum annuum fruits and the anthracnose fungus

Abstract

Plant defensins are low molecular weight basic peptides ranging from 5 to 7 kDa, with capacity of inhibiting various pathogens, including fungi. They are present in different tissues of plants, including floral parts and fruits of Capsicum sp. The IIF48 extract, present in immature fruits of Capsicum annuum inoculated with C. gloeosporioides, was able to inhibit up to 100% growth ‘in vitro’ of the fungus Colletotrichum gloeosporioides. The main objective of this work was the purification and antifungal activity characterization of a defense-related plant defensin-like isolated of the IIF48 immature fruits extract. The IIF48 extract was subjected to HPLC purification and 13 fractions were obtained, followed by a tricine gel electrophoresis to obtain the protein profile. The different fractions were submitted to a growth inhibition assay against C. gloeosporioides fungus. Fraction 7 (F7) was the most active causing 73% inhibition. Because of the higher F7 activity and the presence of only a peptide of approximately 5 kDa this fraction was subjected to N-terminal sequencing. F7 fraction was carried out plasma membrane permeabilization assays, induction of intracellular ROS production analysis and investigated mitochondrial membrane potential. The F7 fraction showed significant inhibitory activity on the tested fungus, besides promoting membrane permeabilization, induction of endogenous ROS production in Colletotrichum cells and impairing mitochondrial functionality. The first 18 amino acid sequence of the F7 fraction peptide suggests homology to plant-like defensin and was named IIFF7Ca. We also concluded that IIFF7Ca peptide has an effective antimicrobial action against the fungus C. gloeosporioides.

Valorization of Capsicum annuum seed extract as an antifungal against Botrytis cinerea

“…Thus, 20 ml of each extract concentration was incorporated separately under aseptic conditions into 200 ml of molten potato dextrose agar (PDA) medium. In this experiment, four concentrations (10,20,30, and 60%) of the aqueous seed extract were tested for their e cacy. After 10 ml of poisoned medium was poured into separate sterile Petri dishes, a one-disc plug (Ø 0.5 cm) of B. cinerea (from a 4-day-old culture) was placed in the center of the poisoned medium.…”

Plant Antimicrobial Peptides as Potential Tool for Topic Treatment of Hidradenitis Suppurativa

“…Other studies reported the prospective use of AMPs against various bacteria ( Fensterseifer et al, 2015 ) and fungi ( Maracahipes et al, 2019 ; dos Santos-Silva et al, 2021 ), indicating their potential as a new therapeutic approach in the treatment of local and systemic infections, including those against bacteria multi-resistant to antibiotics ( Almaaytah et al, 2017 ). The authors highlighted the need to use robust methodologies to identify and circumvent the possible side effects that may appear in the interactions of these molecules.…”

Defensin‐like peptides from Capsicum chinense induce increased ROS, loss of mitochondrial functionality, and reduced growth of the fungus Colletotrichum scovillei

“…17 The pepper genus Capsicum is a promising source of AMPs, including defensins, with a wide range of inhibitory actions. [18][19][20] However, few investigations have been conducted to identify and analyze defensins in Capsicum chinense. In previous studies, Resende et al, 21 obtained a fraction rich in peptides called the G3 fraction, which inhibited the growth of fungi of the genera Colletotrichum and Fusarium.…”