Identification and Functional Analysis of a Defensin CcDef2 from Coridius chinensis

• Published in: International journal of molecular sciences 2022-03, Vol.23 (5), p.2789
• Main Authors: Gong, Tao, Du, Juan, Li, Shang-Wei, Huang, Hai, Qi, Xiao-Lang
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Anti-Bacterial Agents - chemistry; Anti-Infective Agents - pharmacology; Antibacterial activity; Antibiotics; Antimicrobial activity; Antimicrobial agents; antimicrobial peptide; Antimicrobial peptides; Bacteria; Bacterial infections; Bioinformatics; Biological activity; Cations; Chemical bonds; Coliforms; Coridius chinensis; defensin; Defensins; Defensins - chemistry; Defensins - genetics; Defensins - pharmacology; Disulfide bonds; Drug resistance; E coli; Fat body; Functional analysis; Gene expression; Gram-positive bacteria; Heteroptera - metabolism; Immune response; Immune system; Immunosuppressive agents; Infections; Innate immunity; Insects; Mammals; Microorganisms; Molecular weight; Pathogens; Peptides; Peptides - genetics; Phylogenetics; Phylogeny; Polypeptides
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms23052789

belongs to Dinidoridae, Hemiptera. Previous studies have indicated that contains abundant polypeptides with antibacterial and anticancer activities. Antimicrobial peptides (AMPs), as endogenous peptides with immune function, play an indispensable role in the process of biological development and immunity. AMPs have become one of the most potential substitutes for antibiotics due to their small molecular weight and broad-spectrum antimicrobial activity. In this study, a defensin CcDef2 from was characterized based on bioinformatics and functional analyses. The mature peptide of CcDef2 is a typical cationic peptide composed of 43 amino acid residues with five cations, and contains three intramolecular disulfide bonds and a typical cysteine-stabilized αβ motif in defensins. Phylogenetic analysis showed that CcDef2 belongs to the insect defensin family. Analysis of gene expression patterns showed that was expressed throughout developmental stages of with high levels at the nymphal stage and in adult tissues tested with the highest level in the fat body. In addition, the expression was significantly upregulated in adults infected by bacteria. After expressed in BL21(DE3) and renatured, the recombinant CcDef2 showed a significant antibacterial effect on three kinds of Gram-positive bacteria. These results indicate that CcDef2 is an excellent antibacterial peptide and a highly effective immune effector in the innate immunity of . This study provides a foundation for further understanding the function of and developing new antimicrobial drugs.