Recognition sequence of restriction endonuclease KpnI from Klebsiella pneumoniae

Abstract

We have determined the recognition sequence of the restriction endonuclease KpnI , previously isolated from Kiebsiella pneumoniae¹ . The enzyme cleaves the twofold rotationally symmetric sequencev $5′-G-G-T-A-C↓-C-3′3′-C↑-C-A-T-G-G-5′$ at the positions indicated by the arrows, producing 3′ protruding cohesive ends, four nucleotides in length. The specific cleavage site was unambiguously deduced using both 3′ and 5′ end analyses of KpnI generated restriction fragments of simian-virus 40 (SV4O) DNA (1 site), adenovirus-2 (Ad-2) DNA (8 sites), and a plasmid (pCRI) DNA (2 sites).