A major limitation hindering the widespread use of synthetic phages in medical and industrial settings is the lack of an efficient phage-engineering platform. Classical T4 phage engineering and several newly proposed methods are often inefficient and time consuming and consequently, only able to produce an inconsistent range of genomic editing rates between 0.03–3%. Here, we review and present new understandings of the CRISPR/Cas9 assisted genome engineering technique that significantly improves the genomic editing rate of T4 phages. Our results indicate that crRNAs selection is a major rate limiting factor in T4 phage engineering via CRISPR/Cas9. We were able to achieve an editing rate of > 99% for multiple genes that functionalizes the phages for further applications. We envision that this improved phage-engineering platform will accelerate the fields of individualized phage therapy, biocontrol, and rapid diagnostics.

The reactions of antioxidants with superoxide radical were studied by cyclic voltammetry (CV)—and hydrodynamic voltammetry at a rotating ring-disk electrode (RRDE). In both methods, the superoxide is generated in solution from dissolved oxygen and then measured after being allowed to react with the antioxidant being studied. Both methods detected and measured the radical scavenging but the RRDE was able to give detailed insight into the antioxidant behavior. Three flavonoids, chrysin, quercetin and eriodictyol, were studied, their scavenging activity of superoxide was assessed and the molecular structure of each flavonoid was related to its scavenging capability. From our improved and novel RRDE method, we determine the ability of these 3 antioxidants to react with superoxide radical in a more quantitative manner than the classical CV. Density Functional Theory (DFT) and single crystal X-ray diffraction data provide structural information that assists in clarifying the scavenging molecular mechanism. Hydroxyls associated with the A ring, as found in chrysin, scavenge superoxide in a different manner than those found in the B ring of flavonoids, as those in quercetin and eriodictyol.

Advances in synthetic biology, nanotechnology, and genetic engineering are allowing parallel advances in areas such as drug delivery and rapid diagnostics. Although our current visions of nanobots may be far off, a generation of nanobots synthesized by engineering viruses is approaching. Such tools can be used to solve complex problems where current methods do not meet current demands. Assuring safe drinking water is crucial for minimizing the spread of waterborne illnesses. Although extremely low levels of fecal contamination in drinking water are sufficient to cause a public health risk, it remains challenging to rapidly detect Escherichia coli, the standard fecal indicator organism. Current methods sensitive enough to meet regulatory standards suffer from either prohibitively long incubation times or requirement of expensive, impractical equipment. Bacteriophages, tuned by billions of years of evolution to bind viable bacteria and readily engineered to produce custom proteins, are uniquely suited to bacterial detection. We have developed a biosensor platform based on magnetized phages encoding luminescent reporter enzymes. This system utilizes bio-orthogonally functionalized phages to enable site-specific conjugation to magnetic nanoparticles. The resulting phage-based nanobots, when combined with standard, portable field equipment, allow for detection of <10 cfu/100 mL of viable E. coli within 7 h, faster than any methods published to date.

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Phage-based biosensors have shown significant promise in meeting the present needs of the food and agricultural industries due to a combination of sufficient portability, speed, ease of use, sensitivity, and...

Key indicators: single-crystal X-ray study; T = 125 K; mean (C-C) = 0.003 Å; R factor = 0.026; wR factor = 0.064; data-to-parameter ratio = 24.3.In the title compound, C 12 H 9 Br 2 N, the dihedral angle between the benzene rings is 47.32 (5) , whereas the pitch angles, or the angles between the mean plane of each aryl group 'propeller blade' and the plane defined by the aryl bridging C-N-C angle, are 18.1 (2) and 31.7 (2) . No intermolecular N-H hydrogen bonding is present in the crystal; however, there is a short intermolecular BrÁ Á ÁBr contact of 3.568 (1) Å . Related literatureThe title compound is an amine analogue of brominated diphenyl ether flame retardant materials commonly used in household items. For information on environmental and health concerns related to brominated flame retardants, see:

Chalcones (1, 3‐diaryl‐2‐propene‐1‐ones) are natural compounds extracted from fruits and vegetables. Structural and in vitro studies of chalcones have shown they have a large range of biological activities. Previously we have shown that a trihydroxychalcone showed marked antioxidant activity using UV‐vis assays with DPPH, a stable free radical. Additionally, when two oxidatively stressed cell lines, L‐6 myoblasts and THP‐1 monocytes, were treated with chalcone, strong antioxidant activity was seen at nanomolar concentrations, making it an extremely effective free radical scavenger. We now describe the potency of the antioxidant chalcone on mitigating the harmful effects of ROS (reactive oxygen species) in vivo using the model organism Caenorhabditis elegans. The organisms are treated with UV light and paraquat (an intracellular superoxide radical generator) to mimic oxidative stress and then examine if the chalcones’ ability to scavenge the free radicals influences lifespan extension by systematic counting of specimens and evaluation of their behavior under the microscope. If these studies are promising, we will then examine whether chalcone increases thermal tolerance in C. elegans. Finally, we hope to identify genes through multiple genotypes of C. elegans in order to target genes that mediate lifespan and are up‐regulated as a result of chalcone treatment.

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