A Novel Lytic Phage SZW_AS01 of Human Gut Bacteria Alistipes Shahii

Abstract Alisitipes phage SZW_AS01, a novel lytic phage that specifically infects Alistipes shahii, was isolated from wastewater samples in Shenzhen, China. The phage's genome consists of 45,392 bp, with a GC content of 47%. The genome encodes 56 putative open reading frames (ORFs) and 1 tRNA gene. Direct terminal repeats with a length of 55 bp are present at both ends of the genome. Phylogenetic analysis of the amino acid sequences of terminase large subunit shows that phage SZW_AS01 forms a distinct branch from the Siphoviridae family phages, but is far from the Podoviridae and Myoviridae family phages. Transmission electron microscopy confirmed that SZW_AS01 belongs to the Siphoviridae family. To the best of our knowledge, this is the first report of a lytic phage infecting bacteria in the Alistipes genus.