Transposase proteins are necessary for efficient DNA transposition. This family includes insertion sequences from Synechocystis PCC 6803 three of which are characterised as homologous to bacterial IS5- and IS4- and to several members of the IS630-Tc1-mariner superfamily [1].

1: Three insertion sequences from the cyanobacterium Synechocystis PCC6803 support the occurrence of horizontal DNA transfer among bacteria. Cassier-Chauvat C, Poncelet M, Chauvat F; Gene 1997;195:257-266. PMID:9305771