•Whey proteins were partially hydrolysed using thermolysin.•The native and hydrolysed proteins were polymerized using transglutaminase.•The structures of the neo-polymers were analyzed using atomic ...force microscopy.•The solubility, foaming, and emulsifying properties of these polymers were studied.
Whey proteins (WPI) were polymerized with transglutaminase (TGase) before and after partially hydrolyzing the protein with thermolysin to produce protein nanoparticles/polymers. Electrophoresis and atomic force microscopy (AFM) were used to determine the size and structural characteristics of the polymers. The foaming and emulsifying properties of these nanoparticles were studied. The polymerized WPI (WPI-TG) produced more stable foams than the repolymerized WPI hydrolysate (WPIH-TG). In contrast, WPIH-TG produced better emulsions with better storage stability than WPI-TG emulsions. These differences were due to their structure and electrostatic properties: The WPI-TG particles were linear, less than 100 nm in size with lower net negative charge, whereas the WPIH-TG polymers were much larger and were highly negatively charged as judged from zeta potential. This suggested that while protein nanoparticles may provide Pickering stability to both emulsions and foams, strong lateral electrostatic repulsion between nanoparticles within the adsorbed film destabilizes foams but not emulsions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Coronaviruses infect a variety of hosts in the animal kingdom, and while each virus is taxonomically different, they all infect their host
via
the same mechanism. The coronavirus main protease (M
pro
..., also called 3CL
pro
), is an attractive target for drug development due to its essential role in mediating viral replication and transcription. An M
pro
inhibitor, GC376, has been shown to treat feline infectious peritonitis (FIP), a fatal infection in cats caused by internal mutations in the feline enteric coronavirus (FECV). Recently, our lab demonstrated that the feline drug, GC373, and prodrug, GC376, are potent inhibitors of SARS-CoV-2 M
pro
and solved the structures in complex with the drugs; however, no crystal structures of the FIP virus (FIPV) M
pro
with the feline drugs have been published so far. Here, we present crystal structures of FIPV M
pro
-GC373/GC376 complexes, revealing the inhibitors covalently bound to Cys144 in the active site, similar to SARS-CoV-2 M
pro
. Additionally, GC376 has a higher affinity for FIPV M
pro
with lower nanomolar K
i
values compared to SARS-CoV and SARS-CoV-2 M
pro
. We also show that improved derivatives of GC376 have higher potency for FIPV M
pro
. Since GC373 and GC376 represent strong starting points for structure-guided drug design, determining the crystal structures of FIPV M
pro
with these inhibitors are important steps in drug optimization and structure-based broad-spectrum antiviral drug discovery.
Cone-jet electrospray has been proposed for various applications due to its ability to produce monodisperse droplets. The stable operation of the electrospray process is extremely important for ...quality assurance purposes, particularly for applications that require long-term operations. Typically, both the spray current and liquid meniscus shape are used to monitor the working condition of an electrospray. In practice, various factors (operational and environmental) could affect the electrospray operation. Thus, a new spray current control system was developed to improve the stability of a single capillary electrospray operated in the cone-jet mode. The new spray current control system has two control loops: the primary loop for spray current control and the auxiliary loop for meniscus image control. A simple method to characterize the shape of the liquid meniscus and to identify the operational mode of an electrospray was proposed and the performance of the proposed spray current control system was investigated. It was shown that, with the new control strategy, a single capillary electrospray system was able to continuously operate when encountering a severe perturbation (without the over-shooting caused by the previous control strategies) (i.e., the electrospray converged to the target spray current and liquid meniscus shape even when challenged by step perturbation on the spray liquid feeding flow rate).
•A new strategy for the control of spray current in a single capillary electrospray is proposed.•The strategy consists of both primary and axillary loops for spray current and liquid meniscus controls, respectively.•A simple method to characterize the shape of liquid meniscus in the cone-jet mode is proposed.•The performance of new control system was evaluated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We performed studies of the behavior of 3-4-dihydroxylphenylalanine (DOPA) monomers and DOPA-containing chains in water to determine the effect of varying the sequence patterns of DOPA-containing ...chains on the aggregation of peptide conjugates containing both amyloid-forming peptides and DOPA. This research lays the groundwork for designing novel DOPA- and DOPA-amyloid-conjugate-based underwater adhesives that would be capable of multi-surface adhesion. Molecular dynamics simulations were used to investigate the potential aggregation and conformations of DOPA-containing chains and potential DOPA-amyloid design sequences.Atomistic simulations were performed to investigate the behavior of DOPA monomers, (glycine-DOPA) chains, and a KLVFFAE and DOPA-glycine chain conjugate in aqueous environments. This required development of new DOPA model parameters for use with the CHARMM36 force field. Various concentrations of DOPA monomers in water were simulated and cluster analyses were performed to assess the aggregation potential of the monomers. Simulations of a single DOPA-containing chain of (glycine-DOPA) in water were performed, followed by simulations of an initial test DOPA-amyloid conjugate consisting of an alternating DOPA-glycine chain covalently bound to the amyloid-forming peptide, KLVFFAE, in water. While the DOPA monomers themselves did not aggregate significantly at low concentrations, a potential configuration of the test DOPA-amyloid conjugate was observed in which the two halves of the conjugate fold in toward each other, raising a potential concern for adhesive designs containing DOPA and amyloid-forming peptides.Next, we present the results of discontinuous molecular dynamics (DMD) simulations aimed at investigating the effect of the sequence pattern of DOPA-containing chains on the aggregation conformation of conjugates of DOPA and amyloid-forming peptides. For each tested design sequence, the amyloid-forming peptide KLVFFAE was covalently bonded with a DOPAcontaining tail and simulated in implicit water. Analyses of the resulting peptide conformations were performed in which the percentage of ordered secondary structures present at the end of the simulations were calculated and used to build residue-residue contact maps. It was observed that certain patterns of DOPA and glycine in the DOPA-containing tail enhanced the likelihood that the conjugates adopt “favorable conformations” in which the KLVFFAE portions form distinct and ordered β-sheet structures and the DOPA-containing portion remain separated from the KLVFFAE portion, both within the same chain and among different chains.
Abstract only Introduction: Previous studies have reported inverse associations of circulating and tissue levels of pentadecanoic acid (15:0), heptadecanoic acid (17:0) and trans -palmitoleic acid ( ...trans 16:1n-7), which have been proposed as potential biomarkers of dairy fat intake, with risk of type-2 diabetes and certain cardiovascular outcomes. Hypothesis: We assessed the hypothesis that circulating and tissue levels of 15:0, 17:0, trans 16:1n-7 are inversely associated with risk of incident coronary heart disease (CHD) and stroke in a global consortium of prospective studies. Methods: We used data from 15 prospective cohorts in the Fatty Acids and Outcomes Research Consortium. We included adults (age≥18 years) who were free of cardiovascular diseases and had blood or adipose tissue measurements of 15:0, 17:0 or trans 16:1n-7. We used a harmonized analysis protocol with each exposure standardized to the interquintile range (IQR): difference between the 10 th and 90 th percentiles of each fatty acid to conduct new individual participant-level analyses. We harmonized covariate definitions across studies to include demographic, lifestyle and health variables, and levels of other fatty acids associated with CHD or stroke. We used inverse-variance meta-analysis to calculate the pooled relative risks (RR) and 95% confidence intervals (CI) for each outcome. We also calculated Spearman correlation coefficients between levels of each fatty acid exposure and potential dietary determinants of their levels (intakes of total, high-fat and low-fat dairy, meat from ruminant animals, fish and dietary fiber) among 6 studies with dietary data. Results and Conclusions: Among 34,187 participants, 5,790 incident CHD and 3,098 stroke cases were documented during a maximum follow-up of 23.3 years. We did not observe significant associations of any of the fatty acid biomarkers with risk of CHD or stroke. The pooled multivariate RR and 95% CI of CHD per IQR were 0.97 (0.92, 1.02) for 15:0, 0.97 (0.92, 1.02) for 17:0, 1.11 (0.97, 1.26) for trans 16:1n-7, and 0.98 (0.92, 1.04) for the sum of the fatty acids. The respective RR and 95% of stroke were 1.01 (0.93, 1.09) for 15:0, 0.91 (0.81, 1.03) for 17:0, 0.99 (0.83, 1.18) for trans 16:1n-7, and 0.93 (0.85, 1.04) for the summed fatty acids. Additionally, we did not observe significant heterogeneity by age, sex, race/ethnicity, world region, baseline hypertension status or lipid compartment. Circulating and tissue levels of 15:0, 17:0 and trans 16:1n-7 were weakly correlated with intakes of total or high-fat dairy (Spearman correlations r = 0.05 to 0.37) but were not correlated with intakes of low-fat dairy, ruminant meat, fish or dietary fiber r = -0.08 to 0.09. In conclusion, circulating and tissue levels of 15:0, 17:0, trans 16:1n-7 were not associated with risk of CHD or stroke. Our study suggests a limited role for these fatty acids in the etiology of cardiovascular disease.
Anthocyanins present strong anti‐inflammatory properties, thus leading to the potential use as functional food ingredients for the prevention and treatment of chronic inflammatory diseases and ...increased intestinal permeability to endotoxins, notably LPS. However, the differences between individual anthocyanins and their effects on cellular signaling and metabolism need to be further elucidated. In this study, we evaluated the protection afforded by anthocyanins against LPS‐induced inflammatory response in RAW 264.7 macrophages and determined changes in oxygen consumption rates (OCR) and extracellular acidification rates (ECAR) during the macrophage activation. Basal OCR and ECAR increased as the macrophages underwent LPS stimulation from 283.3±38.4 to 361.7±47.9 pmol/min, and from 9.7±2.4 to 27.6±3.8 mpH/min, respectively, suggesting that energy required for activation is rapidly provided by changes in glycolytic pathways. When tested in physiological concentrations (0.1‐3 uM), malvidin and, to a certain degree, delphinidin, were more effective than cyaniding or pelargonidin in the reduction of mRNA and protein biomarkers of inflammation. Different effects exerted by individual anthocyanins suggested that the presence of the methylated hydroxyls on the B ring may be critical for their greater biological activity. Anthocyanin‐treated macrophages developed a distinct metabolic profile with respect to glycolysis versus oxidative phosphorylation, in part by increasing spare respiratory capacity and therefore shifting to mitochondria as their main source of ATP.
Grant Funding Source: Supported by NCSU faculty start up funds to SK.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
ABSTRACT
Ghrelin is a unique peptide gut hormone that requires post‐translational modification to stimulate both feeding and growth hormone release. Ghrelin O‐acyltransferase (GOAT) was identified as ...a specific acyl‐transferase for ghrelin, and recent genetic deletion studies of the Goat gene (Goat−/−) uncovered the role of ghrelin in the regulation of glucose homeostasis. To further understand the physiological functions of the GOAT/ghrelin system, we have conducted a metabolomic and microarray profile of Goat‐null mice, as well as determined Goat expression in different tissues using the lacZ reporter gene. Serum metabolite profile analysis revealed that Goat−/− mice exhibited increased secondary bile acids >2.5‐fold. This was attributed to increased mRNA and protein expression of the ileal sodium‐dependent bile acid transporter (ISBT) in the intestinal and biliary tract. Increased expression of additional solute carrier proteins, including Slc5a12 (>10‐fold) were also detected in the small intestine and bile duct. Goat staining was consistently observed in the pituitary glands, stomach, and intestines, and to a lesser extent in the gallbladder and pancreatic duct. This is the first report that the GOAT/ghrelin system regulates bile acid metabolism, and these findings suggest a novel function of GOAT in the regulation of intestinal bile acid reabsorption.—Kang, K., Schmahl, J., Lee, J. ‐M., Garcia, K., Patil, K., Chen, A., Keene, M., Murphy, A., Sleeman, M. W. Mouse ghrelin‐O‐acyltransferase (GOAT) plays a critical role in bile acid reabsorption. FASEB J. 26, 259–271 (2012). www.fasebj.org
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
This paper reports on the improvement of a previously developed InGaP/GaAs HBT for 24-28V linear power operation. The improvements achieved were: application of dynamic bias circuit which improves ...the ACLR under WCDMA modulation; modification of device technology improving ruggedness to sustain 10:1 VSWR at 30V collector bias under P 1dB driving conditions and over 6 dB of gain compression; maintenance of lifetime and reliability simultaneously. Building blocks of HBT were strung together for higher power and good scaling of performance was achieved supporting the validity of the layout approach and the thermal design. Devices delivering P 1dB equiv 8W under CW conditions provided ACLR equiv -50 dBc at 8.5 dB back-off and 16% efficiency for WCDMA signal (PARequiv8.7 dB) at 2.14 GHz. Lifetime test over 3000 hours was repeated for 28V bias and 0.05mA/mum 2 current density at 315 degree C junction temperature. Therefore, the InGaP/GaAs HBT technology is mature now for the high linearity power amplification
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