Karst Hoogsteen

Karst Hoogsteen (October 1, 1923 – August 10, 2015) was a Dutch-born American biochemist famous for noting a new base-pairing form in DNA, now called Hoogsteen base pairs. These base pairings intercede in the Watson–Crick base pairing, forging a base pair 'triplex'. The base pairs use the N7 nitrogen atom as the acceptor, rather than the N1 as observed in Watson-Crick base pairing. This leads to a twisted, non-linear arrangement.