Research Note: Evaluating the vertical transmission potential of Salmonella Reading in broiler breeders.

Salmonella Reading (S. Reading) recently emerged as a foodborne pathogen causing extensive human outbreaks in North America from consuming contaminated poultry products, mostly from turkeys. Understanding the transmission dynamics of this pathogen is crucial for preventing future outbreaks. This study investigated the ability of S. Reading to colonize the tissues and contaminate eggs of broiler breeders. We utilized 2 S. Reading strains, marked with bioluminescence gene: the outbreak strain RS330 and a reference strain RS326. We used 32 commercially sourced broiler breeder hens, 34 wk of age, randomly assigned to the 2 treatments (16 hens per strain). Each hen was intravaginally inoculated with 108 CFU of the respective strain on d 1 and was rechallenged on d 4. Eggs were collected daily postchallenge to recover bioluminescent S. Reading strains from the external eggshell surface and internal egg contents. On d 7 postchallenge, 10 hens from each treatment group were euthanized. Ovaries, oviducts, and ceca were aseptically collected to detect S. Reading colonization. Results showed that 70.5% (36 of 51) and 34.5% (19 of 55) of external eggshell surfaces, and 4.0% (2 of 50) and 1.8% (1 of 54) of the internal egg contents tested positive for the outbreak and nonoutbreak strains. Additionally, 40.0% of ovaries, 70.0% of oviduct, and 70.0% of ceca samples from the outbreak strain group, and 20.0% of ovaries, 70.0% of oviduct, and 80.0% of ceca samples from nonoutbreak strain group were positive. No significant difference (P = 0.05) was observed in all the findings among the strains except for the eggshell surface contamination. These findings suggest that S. Reading can effectively colonize reproductive tissues, translocate to the ceca, and contaminate the eggs of hens. Future research is needed to determine whether S. Reading can remain viable within the eggs throughout incubation and until hatching.

Evaluation of ATP bioluminescence for rapid determination of farrowing room cleanliness after pressure washing at a commercial sow farm.

Rotavirus and other pathogenic microorganisms are known to cause scours, respiratory infection, and increased mortality, spread from pig to pig via contaminated equipment, insuffcient washing, and improper disinfection processes in farrowing rooms on commercial sow farms. Pig producers have adopted cleaning procedures and biosecurity policies as an attempt to ensure farrowing rooms are free of infectious organisms before the next group of sows is introduced. Adenosine triphosphate (ATP) bioluminescence has been used in other industries to provide real-time feedback on surface cleanliness through the detection of ATP from organic sources. That technology may provide producers a way of objectively characterizing a farrowing room's suitability for a new group of sows to be moved into the farrowing room. Three ATP luminometers (Charm Sciences novaLUM II-X, 3M Clean Trace, and Neogen AccuPoint) were used to estimate relationships between ATP bioluminescence relative light units (RLU) and coliform plate counts (CPC). Five farrowing crate locations and the room entryway floor were swabbed to determine locations within a farrowing crate that can accurately estimate room cleanliness. Coliform plate counts were strongly correlated with Charm novaLUM II-X RLU (r = 0.70, P < 0.01). The Clean-Trace CPCs and RLU (r = 0.48, P < 0.01) were moderately correlated. There was a weak correlation between CPCs and AccuPoint RLU (r = 0.32, P < 0.01). The greatest area of surface contamination was the entryway floor and the sow feeder. Because CPCs and luminometer RLU were correlated, statistical process control charts were developed to provide cleanliness thresholds based on RLU values. Based on an adjusted 3σ from the mean RLU critical limit, 7.7% of crates for the Charm novaLUM II-X, 10.6% of crates for the 3M Clean Trace, and 0% of crates for the Neogen AccuPoint would have failed the critical limit for the sow feeder cleanliness thresholds. Using a similar approach, 11.4% of crates for the Charm novaLUM II-X, 10.5% of crates for the 3M Clean Trace, and 15.2% of crates for the Neogen AccuPoint would have failed the critical limit for the crate sorting bar cleanliness thresholds. These data suggest that ATP bioluminescence may be a reliable method to monitor cleaning effectiveness in farrowing rooms on commercial sow farms. Bioluminescence is a monitoring tool that should be used in conjunction with periodic microbial validation to monitor procedures for cleaning and disinfection.

Dictionary Learning Method Based on K-Sparse Approximation and Orthogonal Procrustes Analysis for Reconstruction in Bioluminescence Tomography.

Bioluminescence tomography (BLT) is one kind of noninvasive optical molecular imaging technology, widely used to study molecular activities and disease progression inside live animals. By combining the optical propagation model and inversion algorithm, BLT enables three-dimensional imaging and quantitative analysis of light sources within organisms. However, challenges like light scattering and absorption in tissues, and the complexity of biological structures, significantly impact the accuracy of BLT reconstructions. Here, we propose a dictionary learning method based on K-sparse approximation and Orthogonal Procrustes analysis (KSAOPA). KSAOPA uses an iterative alternating optimization strategy, enhancing solution sparsity with k-coefficients Lipschitzian mappings for sparsity(K-LIMAPS) in the sparse coding stage, and reducing errors with Orthogonal Procrustes analysis in the dictionary update stage, leading to stable and precise reconstructions. We assessed the method performance through simulations and in vivo experiments, which showed that KSAOPA excels in localization accuracy, morphological recovery, and in vivo applicability compared to other methods.

Direct and Ultrasensitive Bioluminescent Detection of Intact Respiratory Viruses.

Respiratory viruses such as SARS-CoV-2, influenza, and respiratory syncytial virus (RSV) represent pressing health risks. Rapid diagnostic tests for these viruses detect single antigens or nucleic acids, which do not necessarily correlate with the amount of the intact virus. Instead, specific detection of intact respiratory virus particles may be more effective at assessing the contagiousness of a patient. Here, we report GLOVID, a modular biosensor platform to detect intact virions against a background of "free" viral proteins in solution. Our approach harnesses the multivalent display of distinct proteins on the surface of a viral particle to template the reconstitution of a split luciferase, allowing specific, single-step detection of intact influenza A and RSV virions corresponding to 0.1-0.3 fM of genomic units. The protein ligation system used to assemble GLOVID sensors is compatible with a broad range of binding domains, including nanobodies, scFv fragments, and cyclic peptides, which allows straightforward adjustment of the sensor platform to target different viruses.

Autonomous multicolor bioluminescence imaging in bacteria, mammalian, and plant hosts.

Bioluminescence imaging has become a valuable tool in biological research, offering several advantages over fluorescence-based techniques, including the absence of phototoxicity and photobleaching, along with a higher signal-to-noise ratio. Common bioluminescence imaging methods often require the addition of an external chemical substrate (luciferin), which can result in a decrease in luminescence intensity over time and limit prolonged observations. Since the bacterial bioluminescence system is genetically encoded for luciferase-luciferin production, it enables autonomous bioluminescence (auto-bioluminescence) imaging. However, its application to multiple reporters is restricted due to a limited range of color variants. Here, we report five-color auto-bioluminescence system named Nano-lanternX (NLX), which can be expressed in bacterial, mammalian, and plant hosts, thereby enabling auto-bioluminescence in various living organisms. Utilizing spectral unmixing, we achieved the successful observation of multicolor auto-bioluminescence, enabling detailed single-cell imaging across both bacterial and mammalian cells. We have also expanded the applications of the NLX system, such as multiplexed auto-bioluminescence imaging for gene expression, protein localization, and dynamics of biomolecules within living mammalian cells.

Strength of Activation and Temporal Dynamics of BioLuminescent-Optogenetics in Response to Systemic Injections of the Luciferin.

BioLuminescent OptoGenetics ("BL-OG") is a chemogenetic method that can evoke optogenetic reactions in the brain non-invasively. In BL-OG, an enzyme that catalyzes a light producing reaction (i.e., a luciferase) is tethered to an optogenetic element that is activated in response to bioluminescent light. Bioluminescence is generated by injecting a chemical substrate (luciferin, e.g., h-Coelenterazine; h-CTZ) that is catalyzed by the luciferase. By directly injecting the luciferin into the brain, we show that bioluminescent light is proportional to spiking activity, and this relationship scales as a function of luciferin dosage. Here, we build on these previous observations by characterizing the temporal dynamics and dose response curves of bioluminescence generated by luminopsins (LMOs), a proxy of BL-OG effects, to intravenous (IV) injections of the luciferin. We imaged bioluminescence through a thinned skull of mice running on a wheel, while delivering h-CTZ via the tail vein with different dosage concentrations and injection rates. The data reveal a systematic relationship between strength of bioluminescence and h-CTZ dosage, with higher concentration generating stronger bioluminescence. We also found that bioluminescent activity occurs rapidly (< 60 seconds after IV injection) regardless of concentration dosage. However, as expected, the onset time of bioluminescence is delayed as the injection rate decreases. Notably, the strength and time decay of bioluminescence is invariant to the injection rate of h-CTZ. Taken together, these data show that BL-OG effects are highly consistent across injection parameters of h-CTZ, highlighting the reliability of BL-OG as a minimally invasive neuromodulation method.

Taming the Production of Bioluminescent Wood Using the White Rot Fungus Desarmillaria Tabescens.

Although bioluminescence is documented both anecdotally and experimentally, the parameters involved in the production of fungal bioluminescence during wood colonization have not been identified to date. Here, for the first time, this work develops a methodology to produce a hybrid living material by manipulating wood colonization through merging the living fungus Desarmillaria tabescens with nonliving balsa (Ochroma pyramidale) wood to achieve and control the autonomous emission of bioluminescence. The hybrid material with the highest bioluminescence is produced by soaking the wood blocks before co-cultivating them with the fungus for 3 months. Regardless of the incubation period, the strongest bioluminescence is evident from balsa wood blocks with a moisture content of 700-1200%, highlighting the fundamental role of moisture content for bioluminescence production. Further characterization reveals that D. tabescens preferentially degraded hemicelluloses and lignin in balsa wood. Fourier-transform infrared spectroscopy reveals a decrease in lignin, while X-ray diffraction analysis confirms that the cellulose crystalline structure is not altered during the colonization process. This information will enable the design of ad-hoc synthetic materials that use fungi as tools to maximize bioluminescence production, paving the way for an innovative hybrid material that could find application in the sustainable production of light.

Molecular Dynamics Simulation Combined with Neural Relationship Inference and Markov Model to Reveal the Relationship between Conformational Regulation and Bioluminescence Properties of Gaussia Luciferase.

Gaussia luciferase (Gluc) is currently known as the smallest naturally secreted luciferase. Due to its small molecular size, high sensitivity, short half-life, and high secretion efficiency, it has become an ideal reporter gene and is widely used in monitoring promoter activity, studying protein-protein interactions, protein localization, high-throughput drug screening, and real-time monitoring of tumor occurrence and development. Although studies have shown that different Gluc mutations exhibit different bioluminescent properties, their mechanisms have not been further investigated. The purpose of this study is to reveal the relationship between the conformational changes of Gluc mutants and their bioluminescent properties through molecular dynamics simulation combined with neural relationship inference (NRI) and Markov models. Our results indicate that, after binding to the luciferin coelenterazine (CTZ), the α-helices of the 109-119 residues of the Gluc Mutant2 (GlucM2, the flash-type mutant) are partially unraveled, while the α-helices of the same part of the Gluc Mutant1 (GlucM1, the glow-type mutant) are clearly formed. The results of Markov flux analysis indicate that the conformational differences between glow-type and flash-type mutants when combined with luciferin substrate CTZ mainly involve the helicity change of α7. The most representative conformation and active pocket distance analysis indicate that compared to the flash-type mutant GlucM2, the glow-type mutant GlucM1 has a higher degree of active site closure and tighter binding. In summary, we provide a theoretical basis for exploring the relationship between the conformational changes of Gluc mutants and their bioluminescent properties, which can serve as a reference for the modification and evolution of luciferases.

Enhancing Bioluminescence Imaging of Cultured Tissue Explants Using Optical Telecompression.

Long-term observation of single-cell oscillations within tissue networks is now possible by combining bioluminescence reporters with stable tissue explant culture techniques. This method is particularly effective in revealing the network dynamics in systems with slow oscillations, such as circadian clocks. However, the low intensity of luciferase-based bioluminescence requires signal amplification using specialized cameras (e.g., I-CCDs and EM-CCDs) and prolonged exposure times, increasing baseline noise and reducing temporal resolution. To address this limitation, we implemented a cost-effective optical enhancement technique called telecompression, first used in astrophotography and now commonly used in digital photography. By combining a high numerical aperture objective lens with a magnification-reducing relay lens, we significantly increased the collection efficiency of the bioluminescence signal without raising the baseline CCD noise. This method allows for shorter exposure times in time-lapse imaging, enhancing temporal resolution and enabling more precise period estimations. Our implementation demonstrates the feasibility of telecompression for enhancing bioluminescence imaging for the tissue-level network observation of circadian clocks.

Complete genome sequence of Vibrio fischeri strain H905, a planktonic isolate among squid symbiotic congeners.

Here we describe the genome sequence of Vibrio (Aliivibrio) fischeri H905, a non-symbiotic isolate from Kaneohe Bay, Hawaii. Despite its close phylogenetic relationship to squid symbiont strains, H905 is not adept at colonization. Its genome serves as a valuable comparator, illustrating the complex evolutionary dynamics within V. fischeri clades.

Deletion of luxI increases luminescence of Vibrio fischeri.

Bioluminescence in Vibrio fischeri is regulated by a quorum-dependent signaling system composed of LuxI and LuxR. LuxI generates N-3-oxohexanoyl homoserine lactone (3OC6-HSL), which triggers LuxR to activate transcription of the luxICDABEG operon responsible for bioluminescence. Surprisingly, a ∆luxI mutant produced more bioluminescence than the wild type in culture. In contrast, a 4 bp duplication within luxI, resulting in a frameshift mutation and null allele, decreased luminescence tenfold. A second signaling system encoded by ainSR affects bioluminescence by increasing levels of LuxR, via the transcriptional activator LitR, and the N-octanoyl homoserine lactone (C8-HSL) signal produced by AinS is considered only a weak activator of LuxR. However, ainS is required for the bright phenotype of the ∆luxI mutant in culture. When 3OC6-HSL was provided either in the medium or by expression of luxI in trans, all cultures were brighter, but the ∆luxI mutant remained significantly brighter than the luxI frameshift mutant. Taken together, these data suggest that the enhanced bioluminescence due to the LuxI product 3OC6-HSL counteracts a negative cis-acting regulatory element within the luxI gene and that when luxI is absent the C8-HSL signal is sufficient to induce luminescence. IMPORTANCE: The regulation of bioluminescence by Vibrio fischeri is a textbook example of bacterial quorum-dependent pheromone signaling. The canonical regulatory model is that an autoinducer pheromone produced by LuxI accumulates as cells achieve a high density, and this LuxI-generated signal stimulates LuxR to activate transcription of the lux operon that underlies bioluminescence. The surprising observation that LuxI is dispensable for inducing bioluminescence forces a re-evaluation of the role of luxI. More broadly, the results underscore the potential deceptiveness of complex regulatory circuits, particularly those in which bacteria produce multiple related signaling molecules.

Shining new light on naupliar eyes: A novel molecular phylogeny for Pleuromamma (Family: Metridinidae) and the characterization of luciferase and opsin expression.

Pleuromamma (Giesbrecht, 1898) is a cosmopolitan genus of metridinid copepods, with species that perform remarkable diel vertical migrations (DVM) and emit a bioluminescent secretion when disturbed that varies both spectrally and kinetically. Copepod bioluminescence is autogenic and uses luciferase enzymes that catalyze a luciferin, coelenterazine, to produce light. Pleuromamma possess naupliar eyes, relatively simple photosensitive structures used for many visually-guided behaviors. Yet the fundamental molecular unit for vision, the opsin protein, has not been previously described for the family. The light producers and detectors are important to study because DVM is a behavior that mediates significant active elemental fluxes between the upper ocean and midwaters across vast stretches of oceanic habitat, and DVM is guided by visual behaviors, with animals tracking an isolume. Here we provide the first fully resolved molecular phylogeny for Pleuromamma (Family: Metridinidae) and describe the luciferase and opsin gene diversity and expression using de novo assembled transcriptomes. We successfully sequenced and assembled transcriptomes for 10 of 11 described species of Pleuromamma as well as two other metridinid species: Metridia longa and Gaussia princeps. In all species, we obtained coding sequences of one putative rhabdomeric middle wavelength sensitive visual opsin gene, as well as several non-visual opsins - a c-type pteropsin and a tetra-opsin type peropsin. Furthermore, Pleuromamma express luciferases from each of two main evolutionary clades (Luc1 and Luc2), and a single paralog (Luc2a) dominates expression throughout the group. The variation in luciferase number, sequence, and expression among species could lead to different spectral and kinetic properties of bioluminescence and aid in congener recognition.

A light in the dark: a mid-Cretaceous bioluminescent firefly with specialized antennal sensory organs.

The beetle superfamily Elateroidea comprises the most biodiverse bioluminescent insects among terrestrial light-producing animals. Recent exceptional fossils from the Mesozoic era and phylogenomic studies have provided valuable insights into the origin and evolution of bioluminescence in elateroids. However, due to the fragmentary nature of the fossil record, the early evolution of bioluminescence in fireflies (Lampyridae), one of the most charismatic lineages of insects, remains elusive. Here, we report the discovery of the second Mesozoic bioluminescent firefly, Flammarionella hehaikuni Cai, Ballantyne & Kundrata gen. et sp. nov., from the Albian/Cenomanian of northern Myanmar (ca 99 Ma). Based on the available set of diagnostic characters, we interpret the specimen as a female of stem-group Luciolinae. The fossil possesses deeply impressed oval pits on the apices of antennomeres 3-11, representing specialized sensory organs likely involved in olfaction. The light organ near the abdominal apex of Flammarionella resembles that found in extant light-producing lucioline fireflies. The growing fossil record of lampyrids provides direct evidence that the stunning light displays of fireflies were already established by the late Mesozoic.

Buscando Luciérnagas: findings on Mexican fireflies from an 8-year virtual citizen science project.

Fireflies are charismatic and conspicuous animals that often evoke childhood memories, which make firefly watching an emotional and even transformative experience. Citizen science projects have the potential to enhance transformative interactions with nature. Like many insects, firefly populations are declining due to land-use change, urbanization and watershed pollution, but ecological data for this group is scarce, particularly in Mexico. Virtual Citizen Science (VCS) initiatives can serve as a scientific instrument, yield reliable and relevant scientific data, and may also offer a platform to promote broader educational outcomes. We established a VCS project to document fireflies through a Facebook page named Buscando Luciernagas with the following hashtag in every post #veobrillar in 2015. After seven years we complied the gathered data and analyzed the results. We had 647 reports in total, with strong fluctuations from year to year that were correlated with the number of posts and publicity we made each year. The largest number of sightings (319) occurred in 2021, coinciding with a change in our reporting format. Most of the reports came from central Mexico (91.5%), but we had reports from eight states and also received some international reports from nine different countries. Fireflies were most frequently seen in habitats characterized as grasslands (35%) or forests (27%), followed by gardens (17%), vacant lots (9%) and parks (5%) but also paved areas and agricultural lands were reported (3% each). Most citizen scientists reported few fireflies, 1-5 individuals (31%) while only 11% reported more than 50 fireflies per sighting. Our study can serve as a preliminary approach to explore more focused research areas in the future. For example, in areas with no sightings, we could reach out to specific local people to corroborate that there are no fireflies in the region, or in areas with high sightings we could promote conservation measures. Notably, we found it intriguing to discover numerous sightings of fireflies in urban areas, which could offer a potential avenue for further research in urban ecology.

Simultaneously Controlling Inflammation and Infection by Smart Nanomedicine Responding to the Inflammatory Microenvironment.

The overactivated immune cells in the infectious lesion may lead to irreversible organ damages under severe infections. However, clinically used immunosuppressive anti-inflammatory drugs will usually disturb immune homeostasis and conversely increase the risk of infections. Regulating the balance between anti-inflammation and anti-infection is thus critical in treating certain infectious diseases. Herein, considering that hydrogen peroxide (H2O2), myeloperoxidase (MPO), and neutrophils are upregulated in the inflammatory microenvironment and closely related to the severity of appendectomy patients, an inflammatory-microenvironment-responsive nanomedicine is designed by using poly(lactic-co-glycolic) acid (PLGA) nanoparticles to load chlorine E6 (Ce6), a photosensitizer, and luminal (Lum), a chemiluminescent agent. The obtained Lum/Ce6@PLGA nanoparticles, being non-toxic within normal physiological environment, can generate cytotoxic single oxygen via bioluminescence resonance energy transfer (BRET) in the inflammatory microenvironment with upregulated H2O2 and MPO, simultaneously killing pathogens and excessive inflammatory immune cells in the lesion, without disturbing immune homeostasis. As evidenced in various clinically relevant bacterial infection models and virus-induced pneumonia, Lum/Ce6@PLGA nanoparticles appeared to be rather effective in controlling both infection and inflammation, resulting in significantly improved animal survival. Therefore, the BRET-based nanoparticles by simultaneously controlling infections and inflammation may be promising nano-therapeutics for treatment of severe infectious diseases.

Near-infrared in vivo imaging system for dynamic visualization of lung-colonizing bacteria in mouse pneumonia.

In vivo imaging of bacterial infection models enables noninvasive and temporal analysis of individuals, enhancing our understanding of infectious disease pathogenesis. Conventional in vivo imaging methods for bacterial infection models involve the insertion of the bacterial luciferase LuxCDABE into the bacterial genome, followed by imaging using an expensive ultrasensitive charge-coupled device (CCD) camera. However, issues such as limited light penetration into the body and lack of versatility have been encountered. We focused on near-infrared (NIR) light, which penetrates the body effectively, and attempted to establish an in vivo imaging method to evaluate the number of lung-colonizing bacteria during the course of bacterial pneumonia. This was achieved by employing a novel versatile system that combines plasmid-expressing firefly luciferase bacteria, NIR substrate, and an inexpensive, scientific complementary metal-oxide semiconductor (sCMOS) camera. The D-luciferin derivative "TokeOni," capable of emitting NIR bioluminescence, was utilized in a mouse lung infection model of Acinetobacter baumannii, an opportunistic pathogen that causes pneumonia and is a concern due to drug resistance. TokeOni exhibited the highest sensitivity in detecting bacteria colonizing the mouse lungs compared with other detection systems such as LuxCDABE, enabling the monitoring of changes in bacterial numbers over time and the assessment of antimicrobial agent efficacy. Additionally, it was effective in detecting A. baumannii clinical isolates and Klebsiella pneumoniae. The results of this study are expected to be used in the analysis of animal models of infectious diseases for assessing the efficacy of therapeutic agents and understanding disease pathogenesis. IMPORTANCE: Conventional animal models of infectious diseases have traditionally relied upon average assessments involving numerous individuals, meaning they do not directly reflect changes in the pathology of an individual. Moreover, in recent years, ethical concerns have resulted in the demand to reduce the number of animals used in such models. Although in vivo imaging offers an effective approach for longitudinally evaluating the pathogenesis of infectious diseases in individual animals, a standardized method has not yet been established. To our knowledge, this study is the first to develop a highly versatile in vivo pulmonary bacterial quantification system utilizing near-infrared luminescence, plasmid-mediated expression of firefly luciferase in bacteria, and a scientific complementary metal-oxide semiconductor camera. Our research holds promise as a useful tool for assessing the efficacy of therapeutic drugs and pathogenesis of infectious diseases.

New transaminase from Odontosyllis undecimdonta the first potential enzyme of the luciferin biosynthesis pathway.

Among nearly a hundred known bioluminescent systems, only about a dozen have been studied to some extent, and the structures of only a few luciferins have been established. Moreover, the biosynthesis pathway is known only for two of them - the fungal and bacterial ones. Marine polychaetes of the Odontosyllis genus possess bright bioluminescence. The structures of its bioluminescence system key components were recently elucidated, and a possible pathway of the luciferin biosynthesis was proposed. Here we report the transaminase enzyme from Odontosyllis undecimdonta, the first potential participant of the cascade. We demonstrate that the discovered ferment catalyzes the transamination of the cys2DOPA, one of the potential luciferin biosynthetic precursors. The results of the experiments support the hypothesis that the discovered enzyme might be the part of the Odontosyllis luciferin biosynthesis pathway.

Solubilizer of bacterial origin surfactin increases the biological activity of C60 fullerene.

Currently, there exists conflicting data regarding the biological activity of unmodified fullerene C60. Various sources report its toxicity, geroprotective activity, and potential interaction with DNA. Contradictory findings regarding the toxicity of C60 may arise from the use of toxic solvents, as well as the influence of bioavailability and bioactivity on the preparation conditions of C60 suspensions. Furthermore, the microbiota of experimental animals can impact geroprotective activity results by releasing surfactants that facilitate substance penetration through the cell membrane. In this study, we selected conditions for solubilizing fullerene C60 in a solution of surfactin, a surfactant of bacterial origin, as well as in a 2% aqueous solution of TWEEN 80, employing ultrasound. Through bioluminescent analysis using lux biosensors in Escherichia coli MG1655, we observed that C60 in surfactin reduced induced genotoxic and oxidative stress. Given that surfactin enhances membrane permeability to fullerene C60, suspensions of fullerene in designated concentrations of surfactin can be regarded as a DNA protector and antioxidant, warranting further investigation as a promising component of novel drugs.

Class-Wide Analysis of Frizzled-Dishevelled Interactions Using BRET Biosensors Reveals Functional Differences among Receptor Paralogs.

Wingless/Int-1 (WNT) signaling is mediated by WNT binding to 10 Frizzleds (FZD1-10), which propagate the signal inside the cell by interacting with different transducers, most prominently the phosphoprotein Dishevelled (DVL). Despite recent progress, questions about WNT/FZD selectivity and paralog-dependent differences in the FZD/DVL interaction remain unanswered. Here, we present a class-wide analysis of the FZD/DVL interaction using the DEP domain of DVL as a proxy in bioluminescence resonance energy transfer (BRET) techniques. Most FZDs engage in a constitutive high-affinity interaction with DEP. Stimulation of unimolecular FZD/DEP BRET sensors with different ligands revealed that most paralogs are dynamic in the FZD/DEP interface, showing distinct profiles in terms of ligand selectivity and signal kinetics. This study underlines mechanistic differences in terms of how allosteric communication between FZDs and their main signal transducer DVL occurs. Moreover, the unimolecular sensors represent the first receptor-focused biosensors to surpass the requirements for high-throughput screening, facilitating FZD-targeted drug discovery.

Current advances in the development of bioluminescent probes toward spatiotemporal trans-scale imaging.

Bioluminescence imaging has recently attracted great attention as a highly sensitive and non-invasive analytical method. However, weak signal and low chemical stability of the luciferin are conventional drawbacks of bioluminescence imaging. In this review article, we describe the recent progress on the development and applications of bioluminescent probes for overcoming the aforementioned limitations, thereby enabling spatiotemporal trans-scale imaging. The detailed molecular design for manipulation of their luminescent properties and functions enabled a variety of applications, including in vivo deep tissue imaging, long-term imaging, and chemical sensor.