During an infection a certain type of virus forms a tube-like structure to deliver DNA to its host. The tube dissolves when the job is done.
The researchers discovered the mechanism in the phiX174 virus, which attacks E. coli bacteria. The virus, called a bacteriophage because it infects bacteria, is in a class of viruses that do not contain an obvious tail section for the transfer of its DNA into host cells.
“But, lo and behold, it appears to make its own tail,” said Michael Rossmann, a professor of biological sciences at Purdue University.
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