In silico assessment of the association of pathogenicity and metal-resistance potential of Fusarium spp.

Abstract

Genus Fusarium includes ubiquitous species complexes and are often resistant to multiple stressors. Early epidemiological evidence show that metal resistance genes (MRGs) influence the spread of antibiotic resistance genes (ARGs) in microbial communities. More recent evidence points out that this correlation is due to the physical linkage of these genes. Given the utmost importance of Fusarium pathogenicity to agriculture, and the ever-increasing rise in metal or metalloid displacement in the environment - this paper aims to pioneer the investigation of whether pathogenicity determinants also correlate well with MRGs. To provide probable patterns of horizontal gene transfer or incomplete lineage sorting, a species tree was initially defined. Fusarium is unanimously monophyletic from our phylogenetic analysis of 19 concatenated loci. However, saturation analysis show that most of sequences beyond the Terminal Fusarium Clade (TFC) are saturated and are likely to show erroneous phylogenetic relationships. Further analysis of tree topologies also show discordance among loci. Metal-resistance proteins (MRPs) and pathogenicity-related proteins (PRPs) were present in almost all the genomes tested. Remarkably, correlation between MRPs and PRPs among Fusarium is positive and statistically significant. Moreover, there the some of the MRPs and PRPs co-occur significantly more than chance alone. Overall, this suggests that there is a possibility that pathogenicity and metal tolerance proteins among Fusarium may co-occur.