AUTHOR=Amorim Erika Alves da Fonseca , Castro Erima Joussiely Mendonça , Souza Silva Viviane da , Alves Mateus Silva , Dias Léo Ruben Lopes , Melo Maycon Henrique Franzoi , da Silva Ilana Mirian Almeida , Villis Paulo Cesar Mendes , Bonfim Maria Rosa Quaresma , Falcai Angela , Silva Maria Raimunda Chagas , Monteiro-Neto Valério , Aliança Amanda , da Silva Luís Cláudio Nascimento , de Miranda Rita de Cássia Mendonça 

TITLE=Antimicrobial Potential of Streptomyces ansochromogenes (PB3) Isolated From a Plant Native to the Amazon Against Pseudomonas aeruginosa

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.574693

DOI=10.3389/fmicb.2020.574693

ISSN=1664-302X

ABSTRACT=<p>The objective of this study was to evaluate the antibacterial action of filamentous bacteria isolated from the <italic>Byrsonima crassifolia</italic> leaf. An endophytic bacterium has been identified by classical and molecular techniques as <italic>Streptomyces ansochromogene</italic>. Screening for antibacterial action against pathogens with medical relevance (<italic>Klebsiella pneumoniae</italic> ATCC 700603, <italic>Pseudomonas aeruginosa</italic> ATCC 15692, <italic>Staphylococcus aureus</italic> ATCC 6538, <italic>Corynebacterium diphtheriae</italic> ATCC 27012, <italic>Mycobacterium abscessus</italic>, <italic>Cryptococcus gattii</italic> ATCC 24065, and <italic>Cryptococcus neoformans</italic> ATCC 24067) demonstrated activity against the bacterium <italic>P. aeruginosa</italic> ATCC 0030 with inhibition diameter zones (IDZ) of 17.6 ± 0.25 mm in the preliminary screening in solid medium. After fermentation in liquid medium, an IDZ of 19.6 ± 0.46 mm and a minimum inhibitory concentration (MIC) of 0.5 mg/mL were detected. The antibiofilm action was observed with 100% inhibition of biofilm formation at a concentration of 0.250 mg/mL. When the infection curve was prepared, it was observed that the metabolite was effective in protecting the larvae of <italic>Tenebrio molitor</italic>. The metabolite does not show toxicity for eukaryotic cells. The leishmanicidal activity demonstrated that the metabolite presented a dose-dependent effect on the promastigotes forms of <italic>Leishmania amazonensis</italic> growth and the estimated IC<sub>50</sub>/72 h was 71.65 ± 7.4 μg/mL. Therefore, it can be concluded that the metabolite produced by the endophytic bacterium <italic>Streptomyces</italic> sp. is promising for future use as an alternative strategy against bacterial resistance.</p>