CrAss-like phage are a bacteriophage (virus that infects bacteria) family that was discovered in 2014 by cross assembling reads in human fecal metagenomes. In silico comparative genomics and taxonomic analysis have found that crAss-like phages represent a highly abundant and diverse family of viruses. CrAss-like phage were predicted to infect bacteria of the Bacteroidota phylum and the prediction was later confirmed when the first crAss-like phage (crAss001) was isolated on a Bacteroidota host (B. intestinalis) in 2018. The crAss-like phage bacteriophage family is considered highly diverse and consists of four subfamilies- alpha, beta, delta, and gamma- and ten genera within the subfamilies. The subfamilies are defined by crAss-like phage that share 20-40% of their protein-encoding genes while a genera is characterized by crAss-like phage that share >40% of protein-encoding genes. The alpha subfamily consists of the greatest number of crAss-like phage representatives, including p-crAssphage. The assembly of the viral genome is ensured by the translocation of the viral genome to the empty capsids. The genome is packed in specific locations, usually designated as portal vertex, which also functions as the head-to-tail connector as well as the channel through which DNA is injected into the host cell during infection. This is the structure of the unique vertex of the phicrAss001 virion showing a C5 symmetry and determined by cryoEM (PDB code: 7QOH)

#molecularart ... #immolecular ... #vertex ... #capsid ... #assembly ... #genome ... #virus .. #bacteriophage ... #cryoem

Structure rendered with @proteinimaging and depicted with @corelphotopaint