Antibiotic and heavy metal resistant endophytes inhabit Armeria maritima hyperaccumulator

Abstract

AbstractBackground and AimsThe occurrence of heavy metal-resistant bacteria in plants and their role in phytoremediation intensification has been quite well recognized in the last few years. Nevertheless, there is a dearth of information on antibiotic resistance profile of those bacteria. In this study, for the first time endophytic bacteria has been isolated from green parts ofArmeria maritimasp. halleri plant growing on mine-tailing soil in the southern Poland. The resistance profile of bacteria was researched.MethodsBacteria were isolated from internal tissues ofArmeria maritimaplant and characterized: MIC was determined by the plate dilution method using (CH3COO)2Pb and ZnSO4supplemented medium; antibiotic susceptibility test was determined by disk diffusion method according to the EUCAST version 11.0; the whole genome sequencing was performed on MiSeq platform (Illumina). Physicochemical properties of soil were evaluated according to European Standards.ResultsFivePseudomonassp. strains exhibiting high tolerance to heavy metals were resistant to antibiotics, such as aminoglycosides, ß-lactam antibiotics, fosfomycines fluorochinolones, macrolides and glycopeptides. Draft genome sequences analysis estimated genome sizes in a range from 6,182,403bp to 7,401,235bp and a G + C content from 60.0–61.0%. 12 and 11 genes conferring resistance heavy metals and antibiotics were identified, respectively.ConclusionArmeria maritimasubsp. halleri is inhabited by resistant to heavy metals and antibiotic endophytic bacteria identified asPseudomonasspecies. Under the One Health concept the contamination of soil and plants with ARB and ARGs should be monitored and limited and a regulatory framework for safety use of bacterial bioinoculants should be established.