Bacteriophages (viruses that infect bacteria) generally contain double-stranded DNA (dsDNA) as their genetic material. While phages can exhibit all four types of nucleic acid configurations (ssDNA, dsDNA, ssRNA, and dsRNA), more than 90% of known bacteriophages are classified as dsDNA viruses. These genomes are encapsulated in a protein coat called a capsid and often feature complex structures like a head and a tail to aid in injecting DNA into bacterial hosts.

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