A putative antimicrobial peptide from Hymenoptera in the megaplasmid pSCL4 of Streptomyces clavuligerus ATCC 27064 reveals a singular case of horizontal gene transfer with potential applications

Abstract

Streptomyces clavuligerus is a Gram‐positive bacterium that is a high producer of secondary metabolites with industrial applications. The production of antibiotics such as clavulanic acid or cephamycin has been extensively studied in this species; nevertheless, other aspects, such as evolution or ecology, have received less attention. Furthermore, genes that arise from ancient events of lateral transfer have been demonstrated to be implicated in important functions of host species. This approximation discovered relevant genes that genomic analyses overlooked. Thus, we studied the impact of horizontal gene transfer in the S. clavuligerus genome. To perform this task, we applied whole‐genome analysis to identify a laterally transferred sequence from different domains. The most relevant result was a putative antimicrobial peptide (AMP) with a clear origin in the Hymenoptera order of insects. Next, we determined that two copies of these genes were present in the megaplasmid pSCL4 but absent in the S. clavuligerus ATCC 27064 chromosome. Additionally, we found that these sequences were exclusive to the ATCC 27064 strain (and so were not present in any other bacteria) and we also verified the expression of the genes using RNAseq data. Next, we used several AMP predictors to validate the original annotation extracted from Hymenoptera sequences and explored the possibility that these proteins had post‐translational modifications using peptidase cleavage prediction. We suggest that Hymenoptera AMP‐like proteins of S. clavuligerus ATCC 27064 may be useful for both species adaptation and as an antimicrobial molecule with industrial applications.

The evolutionary history of the lethal amanitin biosynthesis genes in Amanita rubescens complex edible mushrooms and its potential health risk

“…Lateral or horizontal gene transfer (HGT) is the genetic transmission between related or unrelated lineages by non-sexual events (Andersson, 2005a;Ayala-Ruano et al, 2019). The gain of single genes or gene clusters from other species is an effective evolutionary alternative to modify and increase the genetic pool of organisms, conferring potential adaptive advantages to themselves (as a selfish genes) or to the host (Husnik & McCutcheon, 2018;Kloesges et al, 2011;Schönknecht et al, 2014;Slot & Hibbett, 2007;Thomas & Nielsen, 2005).…”

“…It is well known that in prokaryotic organisms the ecological similarities (sympatric species or overlapping niches) or physical interactions (symbiotic relationships) instead of their phylogenetic or geographic distances explain the patterns of transferred genes (Andersson, 2005;Kloesges et al, 2011;Kunin et al, 2005). HGT has massive ecologically and evolutionary implications in the ecosystems as niche colonization (competition) or the emergence of new metabolic pathways as pathogenic capability (Ayala-Ruano et al, 2019;Huang, 2013;Van Etten & Bhattacharya, 2020). This phenomenon has been observed also in Eukaryotic organisms, but the transfer mechanisms are still unknown.…”