Dataset Information

Identification and recombinant expression of an antimicrobial peptide (cecropin B-like) from soybean pest Anticarsia gemmatalis.

ABSTRACT:

Abstract

Background

Insects can be found in numerous diverse environments, being exposed to pathogenic organisms like fungi and bacteria. Once these pathogens cross insect physical barriers, the innate immune system operates through cellular and humoral responses. Antimicrobial peptides are small molecules produced by immune signaling cascades that develop an important and generalist role in insect defenses against a variety of microorganisms. In the present work, a cecropin B-like peptide (AgCecropB) sequence was identified in the velvetbean caterpillar Anticarsia gemmatalis and cloned in a bacterial plasmid vector for further heterologous expression and antimicrobial tests.

Methods

AgCecropB sequence (without the signal peptide) was cloned in the plasmid vector pET-M30-MBP and expressed in the Escherichia coli BL21(DE3) expression host. Expression was induced with IPTG and a recombinant peptide was purified using two affinity chromatography steps with Histrap column. The purified peptide was submitted to high-resolution mass spectrometry (HRMS) and structural analyses. Antimicrobial tests were performed using gram-positive (Bacillus thuringiensis) and gram-negative (Burkholderia kururiensis and E. coli) bacteria.

Results

AgCecropB was expressed in E. coli BL21 (DE3) at 28°C with IPTG 0.5 mM. The recombinant peptide was purified and enriched after purification steps. HRMS confirmed AgCrecropB molecular mass (4.6 kDa) and circular dichroism assay showed α-helix structure in the presence of SDS. AgCrecropB inhibited almost 50% of gram-positive B. thuringiensis bacteria growth.

Conclusions

The first cecropin B-like peptide was described in A. gemmatalis and a recombinant peptide was expressed using a bacterial platform. Data confirmed tertiary structure as predicted for the cecropin peptide family. AgCecropB was capable to inhibit B. thuringiensis growth in vitro.

SUBMITTER: Ramos LFC

PROVIDER: S-EPMC7970720 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Publications

Identification and recombinant expression of an antimicrobial peptide (cecropin B-like) from soybean pest <i>Anticarsia gemmatalis</i>.

Ramos Luís Felipe Costa LFC Rangel João Henrique de Oliveira JHO Andrade Guilherme Caldas GC Lixa Carolina C de Castilho Livia Vieira Araujo LVA Nogueira Fábio César Sousa FCS Pinheiro Anderson S AS Gomes Fabio Mendonça FM AnoBom Cristiane Dinis CD Almeida Rodrigo Volcan RV de Oliveira Danielle Maria Perpétua DMP

The journal of venomous animals and toxins including tropical diseases 20210312

<h4>Abstract</h4><h4>Background</h4>Insects can be found in numerous diverse environments, being exposed to pathogenic organisms like fungi and bacteria. Once these pathogens cross insect physical barriers, the innate immune system operates through cellular and humoral responses. Antimicrobial peptides are small molecules produced by immune signaling cascades that develop an important and generalist role in insect defenses against a variety of microorganisms. In the present work, a cecropin B-li ...[more]

PMID: 33796137

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