Table 1.

Summary of tyrosine integrases and their recombination requirements

Phage	Bacteria	attB (bp)	attP (bp)	Host factors	RDF	Length (aa)	Molecular mass (kDa)	References
λ	Escherichia	21	240	IHF and Fis	Xis	72	9	[108,109]
ICEclc	Pseudomonas	18	450	IHFa	-b	—	—	[26]
L5	Mycobacterium	29	240	mIHF	Gp36/Xis	56	6	[54,110–113]
P2	Salmonella	17	220	IHF	Cox	91	10	[114–117]
P22	Salmonella	27	260	IHFc	Xis	116	14	[118–121]
HP1	Hemophilus	18	420	IHF	Cox	79	9	[122–126]

^aNot confirmed but presumed due to the presence of binding sites.

^bDirectionality controlled via differential integrase expression.

^cNot essential for efficient recombination but binding sites present.