AUTHOR=Sabri Miloud , El Handi Kaoutar , Cara Orges , De Stradis Angelo , Valentini Franco , Elbeaino Toufic 

TITLE=Xylella phage MATE 2: a novel bacteriophage with potent lytic activity against Xylella fastidiosa subsp. pauca

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1412650

DOI=10.3389/fmicb.2024.1412650

ISSN=1664-302X

ABSTRACT=<p><italic>Xylella fastidiosa</italic> (<italic>Xf</italic>) is a major phytosanitary threat to global agricultural production. The complexity and difficulty of controlling <italic>Xf</italic> underscore the pressing need for novel antibacterial agents, i.e., bacteriophages, which are natural predators of bacteria. In this study, a novel lytic bacteriophage of <italic>Xf</italic> subsp. <italic>pauca</italic>, namely <italic>Xylella</italic> phage MATE 2 (MATE 2), was isolated from sewage water in southern Italy. Biological characterization showed that MATE 2 possessed a broad-spectrum of antibacterial activity against various phytobacteria within the family <italic>Xanthomonadaceae</italic>, a rapid adsorption time (10 min), and high resistance to a broad range of pH (4–10) and temperatures (4–60°C). Most importantly, MATE 2 was able to suppress the growth of <italic>Xf</italic> subsp. <italic>pauca</italic> cells in liquid culture for 7 days, demonstrating its potential as an effective antibacterial agent against <italic>Xf</italic>. The genomic and electron microscopy analyses revealed that MATE 2 is a new species tentatively belonging to the genus <italic>Carpasinavirus</italic> within the class <italic>Caudoviricetes</italic>, with an isometric capsid head of 60 ± 5 nm along with a contractile tail of 120 ± 7.5 nm. Furthermore, the high-throughput sequencing and <italic>de novo</italic> assembly generated a single contig of 63,695 nucleotides in length; representing a complete genome composed of 95 Open Reading Frames. Bioinformatics analysis performed on MATE 2 genome revealed the absence of lysogenic mediated genes, and genes encoding virulence factors, antibiotic resistance, and toxins. This study adds a new phage to the very short list of <italic>Xf</italic>-infecting lytic phages, whose <italic>in-vitro</italic> antibacterial activity has been ascertained, while its efficacy on <italic>Xf</italic>-infected olive trees in the field has yet to be determined.</p>