The backbone conformation of DNA plays an important role in the indirect readout mechanisms for protein-DNA recognition events. Thus, investigating the backbone dynamics of each step in DNA binding sequences provides useful information necessary for the characterization of these interactions. Here we use 31 P Dynamic NMR to characterize the backbone conformation and dynamics in the Dickerson Dodecamer, a sequence containing the EcoRI binding site, and confirm solid-state 2 H-NMR results showing that the C3pG4 and C9pG10 steps experience unique dynamics and that these dynamics are quenched upon cytosine methylation. In addition, we show that cytosine methylation affects the conformation and dynamics of neighboring nucleotide steps but this effect is localized to only near neighbors and base pairing partners. Lastly, we have been able to characterize the %BII in each backbone step and illustrate that the C3pG4 and C9pG10 favor the non-canonical BII conformation, even at low temperatures. Our results demonstrate that 31 P Dynamic NMR provides a robust and efficient method for characterizing the backbone dynamics in DNA. This allows simple, rapid determination of sequence-dependent dynamical information, providing a useful method for studying trends in protein-DNA recognition events.

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Coronary artery disease (CAD) has typically been treated either medically, with percutaneous coronary intervention (PCI), or with coronary artery bypass grafting (CABG). As advances in stent technology and minimally invasive surgery have developed, a third option has emerged: hybrid coronary revascularization (HCR). In HCR, minimally invasive CABG and PCI are both employed to treat a single patient, often during the same hospital stay. Patients appropriate for this technique vary widely, from low-risk patients with low SYNTAX lesions outside the left anterior descending artery (LAD), to high-risk patients with multiple comorbidities who are felt by the heart team to benefit most by avoiding a sternotomy. Across both our experience and other series in the literature, mortality with HCR is around 1%. Hospital length of stay is less than one week, and typically less than after conventional CABG, but longer than with isolated PCI. Return to baseline activity is substantially shorter after minimally invasive CABG compared to conventional CABG due to the avoidance of a sternotomy; deep sternal wound infections are entirely avoided. Mid-term need for repeat revascularization may be higher with HCR, though randomized data are lacking. In conclusion, HCR is an evolving method to treat multivessel CAD with favorable early results in high volume centers, though growth in the field is limited by surgical experience and success with minimally invasive techniques.