Production of Pumilarin and a Novel Circular Bacteriocin, Altitudin A, by Bacillus altitudinis ECC22, a Soil-Derived Bacteriocin Producer.
Int J Mol Sci
; 25(4)2024 Feb 07.
Article
em En
| MEDLINE
| ID: mdl-38396696
ABSTRACT
The rise of antimicrobial resistance poses a significant global health threat, necessitating urgent efforts to identify novel antimicrobial agents. In this study, we undertook a thorough screening of soil-derived bacterial isolates to identify candidates showing antimicrobial activity against Gram-positive bacteria. A highly active antagonistic isolate was initially identified as Bacillus altitudinis ECC22, being further subjected to whole genome sequencing. A bioinformatic analysis of the B. altitudinis ECC22 genome revealed the presence of two gene clusters responsible for synthesizing two circular bacteriocins pumilarin and a novel circular bacteriocin named altitudin A, alongside a closticin 574-like bacteriocin (CLB) structural gene. The synthesis and antimicrobial activity of the bacteriocins, pumilarin and altitudin A, were evaluated and validated using an in vitro cell-free protein synthesis (IV-CFPS) protocol coupled to a split-intein-mediated ligation procedure, as well as through their in vivo production by recombinant E. coli cells. However, the IV-CFPS of CLB showed no antimicrobial activity against the bacterial indicators tested. The purification of the bacteriocins produced by B. altitudinis ECC22, and their evaluation by MALDI-TOF MS analysis and LC-MS/MS-derived targeted proteomics identification combined with massive peptide analysis, confirmed the production and circular conformation of pumilarin and altitudin A. Both bacteriocins exhibited a spectrum of activity primarily directed against other Bacillus spp. strains. Structural three-dimensional predictions revealed that pumilarin and altitudin A may adopt a circular conformation with five- and four-α-helices, respectively.
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MEDLINE
Assunto principal:
Bacillus
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Bacteriocinas
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article