Structural biology education commonly employs molecular visualization software, such as PyMol, RasMol, and VMD, to allow students to appreciate structure-function relationships in biomolecules. In on-ground, classroombased education, these programs are commonly used on University-owned devices with software preinstalled. Remote education typically involves the use of student-owned devices, which complicates the use of such software, owing to the fact that (a) student devices have differing configurations (e.g., Windows vs MacOS) and processing power, and (b) not all student devices are suitable for use with such software. Smartphones are near-ubiquitous devices, with smartphone ownership exceeding personal computer ownership, according to a recent survey. Here, we show the use of a smartphone-based augmented reality app, Augment, in a structural biology classroom exercise, which students installed independently without IT support. Post-lab attitudinal survey results indicate positive student experiences with this app. Based on our experiences, we suggest that smartphone-based molecular visualization software, such as that used in this exercise, is a powerful educational tool that is particularly well-suited for use in remote education.

Here we demonstrate a switchable DNA electron‐transfer catalyst, enabled by selective destabilization of secondary structure by the denaturant, perchlorate. The system is comprised of two strands, one of which can be selectively switched between a G‐quadruplex and duplex or single‐stranded conformations. In the G‐quadruplex state, it binds hemin, enabling peroxidase activity. This switching ability arises from our finding that perchlorate, a chaotropic Hofmeister ion, selectively destabilizes duplex over G‐quadruplex DNA. By varying perchlorate concentration, we show that the DNA structure can be switched between states that do and do not catalyze electron‐transfer catalysis. State switching can be achieved in three ways: thermally, by dilution, or by concentration.

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† These authors contributed equally to this work. AbstractWe are nearing the end of a remarkable period that began in the 1960s in which semiconductor manufacturers succeeded in shrinking die and feature sizes logarithmically, thus growing transistor counts exponentially with time. As we reach the theoretical physical limits of classical MOSFET semiconductors, DNA is a highly attractive candidate for future miniaturization of microprocessors. Here we show a foundational electronic device -a transistor -can be constructed from DNA. The nanodevice is comprised of two strands, one of which can be selectively switched between a G-quadruplex and duplex or single-stranded conformations. This switching ability arises from our discovery that perchlorate, a chaotropic Hofmeister ion, selectively destabilizes duplex over G-quadruplex DNA. By varying perchlorate concentration, we show that the device can be operated as a switch or signal amplifier. State switching can be achieved in three ways: thermally, by dilution, or by concentration. In each case, when operated in the presence of the cofactor hemin, the device catalyzes electron transfer in only the Gquadruplex state.

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