Dados do Trabalho

Título

Antagonist activity of cutaneous bacteria of the tree-frog Phyllomedusa distincta against WHO critical priority multidrug-resistant pathogens

Introdução

The global spread of multidrug-resistant (MDR) pathogens identified as critical priority pathogens by the WHO poses a serious public health threat that deserves the investigation of new antimicrobials agents. In this regard, frog skin plays a crucial role as the first line of defense against environmental pathogens, and recently has been observed that cutaneous bacteria produce antimicrobial substances that inhibit Batrachochytrium dendrobatidis (Bd), a fungal pathogen causing a significant decline in amphibian populations. Given this, we have hypothesized that bacteria present on frog skin may also possess and additional activity against WHO critical priority pathogens. 

Objetivo (s)

In this study, we investigate the potential of cutaneous bacteria from the tree-frog Phyllomedusa distincta to produce antimicrobial metabolites against international clones of extended-spectrum beta-lactamase and/or carbapenemase producing clinically relevant bacteria.

Material e Métodos

Were isolated skin bacteria from Phyllomedusa distincta, an endemic amphibian of the Brazilian Atlantic Forest, and evaluated their inhibitory activities against international clones of extended-spectrum beta-lactamase (CTX-M), carbapenemase (KPC-2, OXA-23 and NDM-1)-producing Enterobacterales, and metallo-beta-lactamase (SPM-1)-producing Pseudomonas aeruginosa, isolated from hospital infections. A double-layer method was employed to test inhibitory activity and organic crude extracts were obtained by solvent extraction with ethyl acetate.

Resultados e Conclusão

By double-layer method, four cutaneous bacteria identified as Pseudomonas protegens (n=2), and Enterobacter huaxiensis (n=2) showed inhibition against P. aeruginosa SPM-1 (ST277), P. aeruginosa VIM-2 (ST233), Klebsiella quasipneumoniae NDM-1, K. pneumoniae KPC-2 (ST340), Escherichia coli NDM-1 (ST155), and E. coli CTX-M (ST4012). Crude extracts inhibited P. aeruginosa VIM2 (ST233) and K. pneumoniae KPC-2 (ST340) and weak inhibition against Klebsiella quasipneumoniae NDM-1. Interestingly, individuals of P. distincta used in this study were not colonized by Bd, supporting that skin bacteria can represent a function in the host's defense against pathogens. In summary, we report for the first time the inhibitory potential of metabolites produced by cutaneous bacteria from P. distincta against WHO pathogens highlighting a clinical potential that deserves further investigation. To our knowledge, there are also the first reports strains of P. protegens and E. huaxiensis isolated from Brazil.

Palavras Chave

Phyllomedusa distincta; international clone; Brazilian Atlantic Forest; antimicrobial activity.