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Here we report ultrastable synthetic binding pairs between cucurbit[7]uril (CB[7]) and adamantyl- (AdA) or ferrocenyl-ammonium (FcA) as a supramolecular latching system for protein imaging, overcoming the limitations of protein-based binding pairs. Cyanine 3-conjugated CB[7] (Cy3-CB[7]) can visualize AdA- or FcA-labeled proteins to provide clear fluorescence images for accurate and precise analysis of proteins. Furthermore, controllability of the system is demonstrated by treating with a stronger competitor guest. At low temperature, this allows us to selectively detach Cy3-CB[7] from guest-labeled proteins on the cell surface, while leaving Cy3-CB[7] latched to the cytosolic proteins for spatially conditional visualization of target proteins. This work represents a non-protein-based bioimaging tool which has inherent advantages over the widely used protein-based techniques, thereby demonstrating the great potential of this synthetic system. Although protein-ligand pairs are useful tools for bioimaging, they are susceptible to enzymatic degradation and interference from endogenous species. Here, the authors show that a synthetic and bioorthogonal cucurbit[7]uril-guest binding pair can be used to visualize proteins in cells, overcoming limitations of protein-based platforms.

Identifying proteins at organelle contact sites, such as mitochondria-associated endoplasmic reticulum membranes (MAM), is essential for understanding vital cellular processes, yet challenging due to their dynamic nature. Here we report “OrthoID”, a proteomic method utilizing engineered enzymes, TurboID and APEX2, for the biotinylation (Bt) and adamantylation (Ad) of proteins close to the mitochondria and endoplasmic reticulum (ER), respectively, in conjunction with high-affinity binding pairs, streptavidin-biotin (SA-Bt) and cucurbit[7]uril-adamantane (CB[7]-Ad), for selective orthogonal enrichment of Bt- and Ad-labeled proteins. This approach effectively identifies protein candidates associated with the ER-mitochondria contact, including LRC59, whose roles at the contact site were—to the best of our knowledge—previously unknown, and tracks multiple protein sets undergoing structural and locational changes at MAM during mitophagy. These findings demonstrate that OrthoID could be a powerful proteomics tool for the identification and analysis of spatiotemporal proteins at organelle contact sites and revealing their dynamic behaviors in vital cellular processes. Proteomics at the organelle contact site remains challenging due to the spatial and temporal dynamics of proteins. Here, the authors developed OrthoID, a mutually orthogonal dual enzymatic proteomics approach to explore the proteome at the contact site of the endoplasmic reticulum and mitochondria.

Membrane proteomics, the large-scale global analysis of membrane proteins, is often constrained by the efficiency of separating and extracting membrane proteins. Recent approaches involve conjugating membrane proteins with the small molecule biotin and using the receptor streptavidin to extract the labelled proteins. Despite the many advantages of this method, several shortcomings remain, including potential contamination by endogenously biotinylated molecules and interference by streptavidin during analytical stages. Here, we report a supramolecular fishing method for membrane proteins using the synthetic receptor–ligand pair cucurbit[7]uril–1-trimethylammoniomethylferrocene (CB[7]–AFc). CB[7]-conjugated beads selectively capture AFc-labelled proteins from heterogeneous protein mixtures, and AFc-labelling of cells results in the efficient capture of membrane proteins by these beads. The captured proteins can be recovered easily at room temperature by treatment with a strong competitor such as 1,1′- bis (trimethylammoniomethyl)ferrocene. This synthetic but biocompatible host–guest system may be a useful alternative to streptavidin–biotin for membrane proteomics as well as other biological and biotechnological applications. Characterization of plasma membrane proteins is important in understanding fundamental biological processes and developing new drugs, but their separation remains a challenge. Now, a synthetic receptor–ligand pair based on ferrocene derivatives and cucurbit[7]uril is shown to have exceptionally high binding affinity, and enables membrane proteins to be isolated efficiently without any contamination from naturally biotinylated molecules.

The molecular host cucurbit[7]uril forms an extremely stable inclusion complex with the dicationic ferrocene derivative bis(trimethylammoniomethyl)ferrocene in aqueous solution. The equilibrium association constant for this host-guest pair is 3 x 10¹⁵ M⁻¹ (Kd = 3 x 10⁻¹⁶ M), equivalent to that exhibited by the avidin-biotin pair. Although purely synthetic systems with larger association constants have been reported, the present one is unique because it does not rely on polyvalency. Instead, it achieves its extreme affinity by overcoming the compensatory enthalpy-entropy relationship usually observed in supramolecular complexes. Its disproportionately low entropic cost is traced to extensive host desolvation and to the rigidity of both the host and the guest.

Spatiotemporal control of chemical cascade reactions within compartmentalized domains is one of the difficult challenges to achieve. To implement such control, scientists have been working on the development of various artificial compartmentalized systems such as liposomes, vesicles, polymersomes, etc. Although a considerable amount of progress has been made in this direction, one still needs to develop alternative strategies for controlling cascade reaction networks within spatiotemporally controlled domains in a solution, which remains a non-trivial issue. Herein, we present the utilization of audible sound induced liquid vibrations for the generation of transient domains in an aqueous medium, which can be used for the control of cascade chemical reactions in a spatiotemporal fashion. This approach gives us access to highly reproducible spatiotemporal chemical gradients and patterns, in situ growth and aggregation of gold nanoparticles at predetermined locations or domains formed in a solution. Our strategy also gives us access to nanoparticle patterned hydrogels and their applications for region specific cell growth. It is difficult to achieve spatiotemporal control over chemical cascade reactions. Here, the authors report on the generation of transient domains in an aqueous medium using sound induced liquid vibrations allowing for control of chemical gradients and patterns and use this to pattern nanoparticles in hydrogels.

Visible (VIS) bands, such as the 0.675 μm band in geostationary satellite remote sensing, have played an important role in monitoring and analyzing weather and climate change during the past few decades with coarse spatial and high temporal resolution. Recently, many deep learning techniques have been developed and applied in a variety of applications and research fields. In this study, we developed a deep-learning-based model to generate non-existent nighttime VIS satellite images using the Conditional Generative Adversarial Nets (CGAN) technique. For our CGAN-based model training and validation, we used the daytime image data sets of reflectance in the Communication, Ocean and Meteorological Satellite / Meteorological Imager (COMS/MI) VIS (0.675 μm) band and radiance in the longwave infrared (10.8 μm) band of the COMS/MI sensor over five years (2012 to 2017). Our results show high accuracy (bias = −2.41 and root mean square error (RMSE) = 36.85 during summer, bias = −0.21 and RMSE = 33.02 during winter) and correlation (correlation coefficient (CC) = 0.88 during summer, CC = 0.89 during winter) of values between the observed images and the CGAN-generated images for the COMS VIS band. Consequently, our CGAN-based model can be effectively used in a variety of meteorological applications, such as cloud, fog, and typhoon analyses during daytime and nighttime.

Rahul Dev Mukhopadhyay and Kimoon Kim consider how cucurbiturils — pumpkin-shaped macrocycles — went from curiosities to compelling cavitands for a host of applications.

Amyloid fibrils have recently been highlighted for their diverse applications as functional nanomaterials in modern chemistry. However, tight control to obtain a targeted fibril length with low heterogeneity has not been achieved because of the complicated nature of amyloid fibrillation. Herein, we demonstrate that fibril assemblies can be homogeneously manipulated with desired lengths from ~40 nm to ~10 μm by a phase transfer of amyloid proteins based on host-guest chemistry. We suggest that host-guest interactions with cucurbit[6]uril induce a phase transfer of amyloid proteins (human insulin, human islet amyloid polypeptide, hen egg lysozyme, and amyloid-β 1–40 & 1–42) from the soluble state to insoluble state when the amount of cucurbit[6]uril exceeds its solubility limit in solution. The phase transfer of the proteins kinetically delays the nucleation of amyloid proteins, while the nuclei formed in the early stage are homogeneously assembled to fibrils. Consequently, supramolecular assemblies of amyloid proteins with heterogeneous kinetics can be controlled by protein phase transfer based on host-guest interactions.

This study evaluated the life-stage differences in growth and fecal parameters, nutrient digestibility, serum biochemistry, and hematology of Korean Sapsaree dogs. Eighteen healthy Saparees were allotted into three groups according to age (puppy, under 1 yr old; adult, 1-7 yrs old; senior, over 7 yrs old). The study included a 7-day adaptation period and a 10-day experimental period. Body weight change was highest ( < 0.05) in puppies (3.87%), followed by adults and seniors (0.75% and -3.27%). Puppies and adults had greater ( < 0.05) daily food intake than seniors. Adults had greater ( < 0.05) daily fecal output than puppies and seniors. Puppies and adults had greater ( < 0.05) apparent total tract digestibility (ATTD) of dry matter than seniors. The ATTD of crude protein was highest ( < 0.05) in puppies, followed by adults and seniors (88.86%, 84.70%, and 83.12%, respectively). The ATTD of methionine was highest ( < 0.05) in adults, followed by seniors and puppies. Puppies had greater ( < 0.05) the levels of serum total protein, blood urea nitrogen, and creatinine than adults and seniors. Serum albumin level was highest ( < 0.05) in puppies, followed by adults and seniors (4.38, 2.45, and 1.88 g/dL, respectively). At the final day of the study, puppies had greater ( < 0.05) the number of white blood cells than adults and seniors. Adults had greater ( < 0.05) the number of red blood cells and hemoglobin level than puppies and seniors. Our findings suggest that life stage should be considered a key determinant in food formulation and nutritional management, as it influences nutrient digestibility and metabolic status.

This study was conducted to evaluate the effects of dietary mixed selenium [MSe: inorganic selenium (ISe) + organic selenium (OSe)] levels on the growth performance, blood parameters, and fecal microbiota of weaned pigs. In a randomized complete block design (block = initial body weight), 156 weaned pigs were allotted to three dietary treatments (4 pigs per pen; 13 replicates per treatment) for 42 days. Dietary treatments included (1) a non-Se-fortified diet based on corn and soybean meal (CON), (2) CON + 0.15 ppm ISe and 0.15 ppm OSe (MSe3), and (3) CON + 0.25 ppm ISe and 0.25 ppm OSe (MSe5). Pigs fed both MSe diets showed no effects on growth performance or diarrhea frequency compared with those fed the CON diet. However, pigs fed MSe3 and MSe5 had higher serum interleukin-6 ( p  = 0.021, linear p  = 0.011) on day 7 and higher Se concentrations ( p = 0.002, linear p = 0.001) on day 42 than those fed the CON. In addition, pigs fed different levels of MSe exhibited quadratic ( p  = 0.054) and linear ( p  = 0.069) effects on the number of white blood cells and hematocrit on day 42 compared with those fed CON, respectively. Moreover, the MSe3 group had higher total protein concentration ( p  = 0.049, quadratic p  = 0.026) on day 42 than the CON group, and the MSe5 group had lower blood urea nitrogen concentration ( p  = 0.094, linear p  = 0.033). There were no differences in alpha diversity indices of fecal microbiota among dietary treatments. However, beta diversity indices based on the Bray–Curtis dissimilarity were clustered differently ( r 2  = 0.56, p  = 0.001) among dietary treatments. Pigs fed the MSe5 diet showed an increase in the relative abundance of phylum Bacteroidetes [false discovery rate (FDR) adjusted p  = 0.004], families Barnesiellaceae (FDR adjusted p  = 0.006) and Veillonellaceae (FDR adjusted p  = 0.006), genera Barnesiella (FDR adjusted p  = 0.023) and Megasphaera (FDR adjusted p  = 0.023), and species Barnesiella intestinihominis (FDR adjusted p  = 0.016) and Megasphaera elsdenii (FDR adjusted p  = 0.019) compared with those fed the CON diet. In conclusion, dietary MSe modulated the systemic health parameters and fecal microbial community in weaned pigs.