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Smith-Zaitlik, T.

Publications and source records attributed to Smith-Zaitlik, T..

2 recordsLinked to original sources

Phage vB_KmiS-Kmi2C infects members of the Klebsiella oxytoca complex and represents a novel genus of lytic bacteriophage

AIMSThis study aimed to characterise the lytic phage vB_KmiS-Kmi2C, isolated from sewage water on a GES-positive strain of Klebsiella michiganensis. METHODS AND RESULTSComparative phylogenetic and network-based analyses were used to characterise the genome of phage vB_KmiS-Kmi2C (circular genome of 42,234 bp predicted to encode 55 genes), demonstrating it shared little similarity with other known phages. The phage was lytic on clinical strains of K. oxytoca (n=2) and K. michiganensis (n=4), and was found to both prevent biofilm formation and disrupt established biofilms produced by these strains. CONCLUSIONSWe have identified a phage capable of killing clinically relevant members of the Klebsiella oxytoca complex (KoC). The phage represents a novel virus family (proposed name Dilsviridae) and genus (proposed name Dilsvirus). SIGNIFICANCE AND IMPACT OF THE STUDYIdentification a novel lytic phage active against clinically relevant strains of the KoC provides an alternative to antibiotics to treat these increasingly antimicrobial-resistant opportunistic pathogens. The unusual way in which the phage can disrupt established biofilms may allow us to identify novel phage-based approaches for biofilm remediation in the future.

microbiology↗

Extended genomic analyses of the broad-host-range phages vB_KmiM-2Di and vB_KmiM-4Dii reveal slopekviruses have highly conserved genomes

High levels of antimicrobial resistance among members of the Klebsiella oxytoca complex (KoC) have led to renewed interest in the use of bacteriophage (phage) therapy to tackle infections caused by these bacteria. In this study we characterized two lytic phages, vB_KmiM-2Di and vB_KmiM-4Dii, that were isolated from sewage water against two GES-5-positive Klebsiella michiganensis strains (PS_Koxy2 and PS_Koxy4, respectively). ViPTree analysis showed both phages belonged to the genus Slopekvirus. rpoB gene-based sequence analysis of 108 presumptive K. oxytoca isolates (n=59 clinical, n=49 veterinary) found K. michiganensis to be more prevalent (46 % clinical and 43 % veterinary, respectively) than K. oxytoca (40 % clinical and 6 % veterinary, respectively). Host range analysis against these 108 isolates found both vB_KmiM-2Di and vB_KmiM-4Dii showed broad lytic activity against KoC species. Several putative homing endonuclease genes were encoded within the genomes of both phages, which may contribute to their broad host range. Pangenome analysis of 24 slopekviruses found that genomes within this genus are highly conserved, with more than 50 % of all predicted coding sequences representing core genes at [≥]95 % identity and [≥]70 % coverage. Given their broad host ranges, our results suggest vB_KmiM-2Di and vB_KmiM-4Dii represent attractive potential therapeutics. In addition, current recommendations for phage-based pangenome analyses may require revision.

microbiology↗