We study internal motions of nucleic acids and proteins, to establish relations to their biological functions. Examples include: Mobility of intact ribosomes (PNAS 2004, 10949); structure and internal motions of a RNA reverse transcriptase binding site (NAR 2002, 4803). New projects involve function of Helicobacter adhesins, internal motions of DNA and RNA, and folding of an RNA thermosensor.
Methods development includes new isotope labelling schemes (NAR 2002, 1639) and new NMR experiments. The off-resonance ROESY experiment gives qualitatively new insight into internal motions (JACS 2002, 5881), such as internal motions of H,H vectors used in structure calculations, and of intermolecular contacts.
Reflecting metabolic regulation, enzyme isotope effects induce variable distributions of stable heavy isotopes among non-equivalent intramolecular positions of non-symmetrical metabolites. We measure this variation by NMR and deduce metabolic regulation.
Biomolecular Function at Global Scale
Relating to Global Climate Change, we apply this to deuterium in tree rings. We can separate deuterium signals from climate and physiology, and study plant-climate interactions on time scales of centuries. Plant-climate interactions affect both future climate and agricultural productivity, therefore their understanding is crucial for climate prediction and adaptation to Climate Change.