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Author Spotlight: Investigating Bacteriophage-Induced Immune Responses in Gnotobiotic Mice
Published on: January 26, 2024
The Sequence of Two Bacteriophages with Hypermodified Bases Reveals Novel Phage-Host Interactions
Andrew M Kropinski1,2, Dann Turner3, John H E Nash4
1Department of Food Science, University of Guelph, Guelph, ON N1G 2W1, Canada. Phage.Canada@gmail.com.
Abstract:
Bacteriophages SP-15 and ΦW-14 are members of the Myoviridae infecting Bacillus subtilis and Delftia (formerly Pseudomonas) acidovorans, respectively. What links them is that in both cases, approximately 50% of the thymine residues are replaced by hypermodified bases. The consequence of this is that the physico-chemical properties of the DNA are radically altered (melting temperature (Tm), buoyant density and susceptibility to restriction endonucleases). Using 454 pyrosequencing technology, we sequenced the genomes of both viruses. Phage ΦW-14 possesses a 157-kb genome (56.3% GC) specifying 236 proteins, while SP-15 is larger at 222 kb (38.6 mol % G + C) and encodes 318 proteins. In both cases, the phages can be considered genomic singletons since they do not possess BLASTn homologs. While no obvious genes were identified as being responsible for the modified base in ΦW-14, SP-15 contains a cluster of genes obviously involved in carbohydrate metabolism.
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