Identification and chemical synthesis of a new defensin present in the transcriptome of the fire salamander (Salamandra salamandra): Modelling and target against spike glycoprotein of SARS-CoV-2
Ana Luisa1,*, Vladimir Costa2, Samuel Ribeiro Costa3, Wanessa Feliz Cabral1, Jefferson Rocha4, Guilherme Dotto Brand3, Massuo Jorge Kato5, Alexandra Plácido6, José Roberto S. A. Leite1
1Núcleo de Pesquisa em Morfologia e Imunologia Aplicada, NuPMIA, Faculdade de Medicina, Universidade de Brasília, UnB, Brasília, Brasil;
2Centro de Ciências da Saúde, CCS, Universidade Federal do Piauí, Teresina, PI, Brasil;
3Instituto de Química, IQ, Universidade de Brasília, UnB, Brasília, DF, Brasil;
4Universidade Federal do Maranhão, Campus São Bernardo, UFMA, Maranhão, Brasil;
5Instituto de Química, IQ, Universidade de São Paulo, USP, São Paulo, Brasil;
6LAQV/REQUIMTE, Departamento de Química e Bioquímica, FCUP, Porto, Portugal.
*analuisaanbarros@gmail.com
Antimicrobial peptides have been shown to be a promising alternative in the development of new drugs for use in the therapeutic management of various infectious diseases. The recent pandemic has highlighted the importance of science to be prepared to meet these challenges immediately. Bioprospection and characterization of new molecules are of utmost strategic relevance to have tools available for shortly use in the research and development of drugs for viral treatment and management. Amphibians are a rich source of several attractive compounds that include antimicrobial peptides. This work aiming the identifying and synthesis a peptide in Salamandra salamandra transcriptome and access the target against spike protein SARS-CoV-2 in silico. The peptide was identified through the transcriptome of the S. salamandra species using an RNA-Seq sample dataset. The peptide was obtained by Solid Phase Synthesis using the Fmoc/t-butyl method. High performance liquid chromatography was used for the purification of the peptide and its mass and structure were determined by mass spectrometry (MALDI/TOF). Analysis by tblastn produced a transcript that was used for translation and identity search by blastn with the NCBI database. This transcript had 78.72% identity with the CFBD-1 defensin sequence of Cynops fudingensis and 95 to 70% with the defensin of other species. 3D molecular docking assays performed between the enzyme-ligand complex with Spike/ACE and peptide ligand demonstrates its interaction with the active binding site.
Keyword: Salamandra salamandra; Peptide; SARS-CoV-2; bioactive peptides.