2026-06-29T07:44:11Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/1033322025-03-18T15:26:24Zcom_20.500.14352_14col_20.500.14352_15

Lafuente, Irene Sevillano, Ester Peña Vidal, Nuria Cuartero, Alicia Hernández Cruza, Pablo Elpidio Cintas Izarra, Luis Miguel Muñoz Atienza, Estefanía Borrero Del Pino, Juan 2024-04-22T14:29:09Z 2024-04-22T14:29:09Z 2024-02-07 : Lafuente, I.; Sevillano, E.; Peña, N.; Cuartero, A.; Hernández, P.E.; Cintas, L.M.; Muñoz-Atienza, E.; Borrero, J. Production of Pumilarin and a Novel Circular Bacteriocin, Altitudin A, by Bacillus altitudinis ECC22, a Soil-Derived Bacteriocin Producer. Int. J. Mol. Sci. 2024, 25, 2020. https://doi.org/10.3390/ ijms25042020 10.3390/ijms25042020 https://hdl.handle.net/20.500.14352/103332 https://doi.org/10.3390/ijms25042020 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. eng http://creativecommons.org/licenses/by/4.0/ open access Attribution 4.0 International Production of Pumilarin and a Novel Circular Bacteriocin, Altitudin A, by Bacillus altitudinis ECC22, a Soil-Derived Bacteriocin Producer journal article