Abstract
Understanding the relationship between bacteriophage (phage) classification and target receptors is crucial for phage ecology and applied research. In this study, we compared 13 previously isolated Escherichia coli phages based on physiological characteristics, whole-genome sequences, and tail fiber protein phylogenetics. We combined genomic analysis and lipopolysaccharide (LPS) structural analysis of phage-resistant E. coli strains to identify target receptors of the phages. The results revealed that phylogenetically distinct E. coli phages target different sites in the LPS R-core region (modified by WaaV, WaaW, WaaT, and WaaY), membrane proteins (NfrB, TolA, YhaH), or flagella. Notably, subtle chemical modifications of LPS (such as Heptose phosphorylation) were shown to be important for E. coli phage recognition. Furthermore, physiological characteristics, tail fiber phylogenetics, and whole genome analysis independently classified the phages into five identical groups. Meanwhile, classification based on target receptors placed them into six groups, which was very similar to the grouping pattern based on the three independent parameters described above. Our results suggest that phage phenotypes and genotypes are closely related to target receptor specificity and the physiological characteristics of E. coli phages. Here, we elucidated the diversity and specificity of E. coli phage target receptors, providing new insights into the classification of E. coli phages and phage-host interactions.
Competing Interest Statement
The authors have declared no competing interest.
