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Siderophores are small molecules used to specifically transport iron into bacteria via related receptors. By adapting siderophores and hijacking their pathways, we may discover an efficient and selective way to target microbes. Herein, we report the synthesis of a siderophore-fluorophore conjugate VF-FL derived from vibrioferrin (VF). Using flow cytometry and fluorescence microscopy, the probe selectively labeled vibrios, including V. parahaemolyticus, V. cholerae, and V. vulnificus, even in the presence of other species such as S. aureus and E. coli. The labeling is siderophore-related and both iron-limited conditions and the siderophore moiety are required. The competitive relationship between VF-FL and VF in vibrios implies an unreported VF-related transport mechanism in V. cholerae and V. vulnificus. These studies demonstrate that the siderophore scaffold provides a method to selectively target microbes expressing cognate receptors under iron-limited conditions.

We developed an ultrasound-chemical hybrid tool to precisely manipulate cellular activities. A focused ultrasound coupled with gas-filled microbubbles were used to rapidly trigger the influx of membrane-impermeable chemical dimerizers into living cells to regulate protein dimerization and location without inducing noticeable toxicity. With this system, we demonstrated the successful modulation of phospholipid metabolism triggered by a short pulse of ultrasound exposure. Our technique offers a powerful and versatile tool for using ultrasound to spatiotemporally manipulate the cellular physiology in living cells.

A direct and selective method for the functionalization of aerobactin has been described. Selectivity was achieved by masking the functioning carboxylate via iron-chelation, leaving the two remaining carboxylates for direct modification. Both mono- and bis-functionalized aerobactin effectively targeted pathogenic bacteria, showing a facile method with prospective applications.

Siderophores, such as enterobactin (Ent), are small molecules that can be selectively imported into bacteria along with iron by cognate transporters. Siderophore conjugates are thus a promising strategy for delivering functional reagents into bacteria. In this work, we present an easy-to-perform, one-pot chemoenzymatic synthesis of functionalized monoglucosylated enterobactin (MGE). When functionalized MGE is conjugated to a rhodamine fluorophore, which affords RhB-Glc-Ent, it can selectively label Gram-negative bacteria that utilize Ent, including some E. coli strains and P. aeruginosa. V. cholerae, a bacterium that utilizes linearized Ent, can also be weakly targeted. Moreover, the targeting is effective under iron-limiting but not iron-rich conditions. Our results suggest that the RhB-Glc-Ent probe is sensitive not only to the bacterial strain but also to the iron condition in the environment.

The state-of-the-art prosthetic devices have been successfully approved as critical approach to provide at least partial reconstruction for physiological diseases by replacing a damaged tissue or organ. Invariably, they are always aspired to have lower power consumption despite the battery or the battery-less implementation. This paper presents an energy-aware baseband circuitry concerned about the next-generation multi-channel prostheses especially for the retinal implant in which an inductive-coil link is preferred to fulfill the need of power delivery for providing safer tissue-machine interfaces in the intraocular environment. The extended lifetime for those of the battery-dependent implants can be also achieved by adopting such a power-efficient scheme. The proposed system is a 16-channel-based on-electrode multiplexing design, which can deal with up to 40 frame/sec with 240 stimulus channels in mode I and 3 times the resolution at the same frame rate in mode II under a carrier frequency of 2 MHz. A prototypical chip was implemented in a 0.18mum CMOS process and the experiment has also been carried out as proof of concept.