DataSheet_3_In silico characterization of Cnidarian’s antimicrobial peptides.fasta

The characterization of active compounds in Cnidaria sheds light on a large bank of substances against multiresistant bacteria related to diseases in humans, which makes it a cutting edge with a repertoire of antimicrobial molecules worthy of bioprospecting analysis. Thus, the main nabof this research was to characterize antimicrobial peptides (AMP) belonging to the defensin family in different species of Cnidarians through bioinformatic approaches. To this, an exhaustive search was carried out for sequences homologous to antimicrobial peptides belonging to the defensin family in genomes availables for Cnidarians. Also, 3D models of AMP were obtained by modeling based on homology, functional characterization of peptides found was performed with machine learning approaches. Characterization of twelve peptides derived from 11 Cnidarian species was possible due to 3D modeling, which showed structural similarity with defensins reported in several species such as Nasonia vitripennis, Pisum sativum, Solanum lycopersicum, and Aurelia aurita. Also, different physicochemical properties such as hydrophobic moment, hydrophobicity, net charge, amphiphilic index, and isoelectric point were evaluated. These peptides showed values ​​that are ideal for AMP. Further, functional characterization showed a bactericidal potential of 20 peptides against multiresistant bacteria Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae. These peptides with action potential were found in 17 species from Cnidarians and obtained by homology through the defensin Aurelin, described in the Cnidarian Aurelia aurita, and Mus musculus’ Beta-defensin 7. Finally, a phylogenetic tree was performed, it showed that defensins are distributed in all Cnidarians regardless of the taxonomic group. Thus, the origin of defensins in the Phylum Cnidaria is not monophyletic. Our results show that Cnidaria has AMP with structural and physicochemical characteristics similar to those described in defensins of insects, mammals, and plants. The structural characteristics of these peptides, their physicochemical properties, and their functional potential outline them as promising templates for the discovery of new antibiotics.

刺胞动物门（Cnidaria）中活性化合物的表征研究，可为防控人类疾病相关的多重耐药菌提供海量候选物质，使其成为拥有大量值得开展生物勘探分析的抗菌分子的前沿研究领域。本研究的核心目标为：借助生物信息学方法，对不同刺胞动物物种体内隶属于防御素家族（defensin family）的抗菌肽（antimicrobial peptides，AMP）进行表征分析。为此，研究团队针对已公开的刺胞动物基因组中与防御素家族抗菌肽同源的序列开展了全面检索。此外，通过同源建模获得了抗菌肽的三维结构模型，并借助机器学习方法对所发现的肽类进行功能表征。借助三维建模，研究人员成功对11种刺胞动物来源的12条肽段完成表征，结果显示这些肽段与多个物种中已报道的防御素存在结构相似性，包括丽蝇蛹集金小蜂（Nasonia vitripennis）、豌豆（Pisum sativum）、番茄（Solanum lycopersicum）以及海月水母（Aurelia aurita）。同时，研究还评估了多条理化性质参数，包括疏水矩、疏水性、净电荷、两亲性指数与等电点，结果显示这些肽段的参数均符合抗菌肽的理想特征。进一步的功能表征结果表明，20条肽段对多重耐药菌——大肠埃希氏菌（Escherichia coli）、铜绿假单胞菌（Pseudomonas aeruginosa）与肺炎克雷伯菌（Klebsiella pneumoniae）——具备杀菌活性。这类具备抗菌活性的肽段来自17种刺胞动物，其同源建模模板分别为刺胞动物海月水母中发现的防御素Aurelin，以及小家鼠（Mus musculus）的β防御素7。最后，研究构建了系统发育树，结果显示防御素广泛分布于所有刺胞动物类群中，不受分类学类群限制，表明刺胞动物门内防御素的起源并非单系起源。本研究结果证实，刺胞动物体内的抗菌肽具备与昆虫、哺乳动物及植物中防御素相似的结构与理化特征。这类肽段的结构特征、理化性质与功能潜力，使其成为新型抗生素研发的极具前景的候选模板。