The site-specific DNA-methylase M . BspST5I has been isolated from Bac
illus species ST5 and purified to functional purity. M . BspST5I prote
cts DNA from endonuclease R . BspST5I, which recognizes the nonpalindr
omic sequence [GRAPHIC] M . BspST5I is an adenine-specific methylase.