Table 7.1.

Termini of tailed-phage virion DNAs.

Terminus type	Prototype phage	Replication strategy
Cohesive ends
5′-single-strand extension	λ P2	Rolling circle→concatemer
		Circle→circle
3′-single-strand extension	HK97	Rolling circle→ concatemer*
Circularly permuted direct terminal repeats†
	T4	Complex→concatemer
	P22	Rolling circle→concatemer
	P1	Rolling circle→concatemer
Host DNA at termini
	Mu	Duplicative transposition into host DNA
Exact direct terminal repeats
Short (few hundred base pairs)	T7	Linear→concatemer
Long (thousands of base pairs)	SPO1	Complex→concatemer
	T5	Complex→concatemer
Covalent terminal protein
	ϕ29	Protein-primed linear→linear

^†Individual virions of these phages have chromosomes that terminate at many different places on the genome sequence, and the length of the terminal repeat varies among individual virions (see text).

^*Genomic analysis predicts this mode of replication, but it has not been studied experimentally.