Reactive Amino Research Articles

Activity-Based Protein Profiling at the Host-Pathogen Interface.

Activity-based protein profiling (ABPP) is a technique for selectively detecting reactive amino acids in complex proteomes with the aid of chemical probes. Using probes that target catalytically active enzymes, ABPP can rapidly define the functional proteome of a biological system. In recent years, this approach has been increasingly applied to globally profile enzymes active at the host-pathogen interface of microbial infections. From in vitro co-culture systems to animal models of infection, these studies have revealed enzyme-mediated mechanisms of microbial pathogenicity, host immunity, and metabolic adaptation that dynamically shape pathogen interactions with the host.

Pathogenic Acanthamoeba castellanii Secretes the Extracellular Aminopeptidase M20/M25/M40 Family Protein to Target Cells for Phagocytosis by Disruption.

Acanthamoeba is free-living protist pathogen capable of causing a blinding keratitis and granulomatous encephalitis. However, the mechanisms of Acanthamoeba pathogenesis are still not clear. Here, our results show that cells co-cultured with pathogenic Acanthamoeba would be spherical and floated, even without contacting the protists. Then, the Acanthamoeba protists would contact and engulf these cells. In order to clarify the contact-independent pathogenesis mechanism in Acanthamoeba, we collected the Acanthamoeba-secreted proteins (Asp) to incubate with cells for identifying the extracellular virulent factors and investigating the cytotoxicity process. The Asps of pathogenic Acanthamoeba express protease activity to reactive Leu amino acid in ECM and induce cell-losing adhesion ability. The M20/M25/M40 superfamily aminopeptidase protein (ACA1_264610), an aminopeptidase be found in Asp, is upregulated after Acanthamoeba and C6 cell co-culturing for 6 h. Pre-treating the Asp with leucine aminopeptidase inhibitor and the specific antibodies of Acanthamoeba M20/M25/M40 superfamily aminopeptidase could reduce the cell damage during Asp and cell co-incubation. These results suggest an important functional role of the Acanthamoeba secreted extracellular aminopeptidases in the Acanthamoeba pathogenesis process. This study provides information regarding clinically pathogenic isolates to target specific molecules and design combined drugs.

Identification of metabolism-associated genes and pathways involved in different stages of clear cell renal cell carcinoma.

The lack of early diagnostic markers and novel therapeutic targets for clear cell renal cell carcinoma (ccRCC) negatively affects patient prognosis. Cancer metabolism is an attractive area for the understanding of the molecular mechanism of carcinogenesis. The present study attempted to identify metabolic changes from the view of the expression of metabolism-associated genes between control samples and those of ccRCC at different disease stages. Data concerning ccRCC gene expression obtained by RNA-sequencing was obtained from The Cancer Genome Atlas and data on metabolism-associated genes were extracted using the Recon2 model. Following analysis of differential gene expression, multiple differentially expressed metabolic genes at each tumor-node-metastasis disease stage were identified, compared with control non-disease samples: Metabolic genes (305) were differentially expressed in stage I disease, 323 in stage II disease, 355 in stage III disease and 363 in stage IV disease. Following enrichment analysis for differential metabolic genes, 22 metabolic pathways were identified to be dysregulated in multiple stages of ccRCC. Abnormalities in hormone, vitamin, glucose and lipid metabolism were present in the early stages of the disease, with dysregulation to reactive oxygen species detoxification and amino acid metabolism pathways occurring with advanced disease stages, particularly to valine, leucine, and isoleucine metabolism, which was substantially dysregulated in stage IV disease. The xenobiotic metabolism pathway, associated with multiple cytochrome P450 family genes, was dysregulated in each stage of the disease. This pathway is worthy of substantial attention since it may aid understanding of drug resistance in ccRCC. The results of the present study offer information to aid further research into early diagnostic biomarkers and therapeutic targets of ccRCC.

Phthalocyanine-Conjugated Upconversion NaYF4 :Yb3+ /Er3+ @SiO2 Nanospheres for NIR-Triggered Photodynamic Therapy in a Tumor Mouse Model.

Photodynamic therapy (PDT) has garnered immense attention as a minimally invasive clinical treatment modality for malignant cancers. However, its low penetration depth and photodamage of living tissues by UV and visible light, which activate a photosensitizer, limit the application of PDT. In this study, monodisperse NaYF4 :Yb3+ /Er3+ nanospheres 20 nm in diameter, that serve as near-infrared (NIR)-to-visible light converters and activators of a photosensitizer, were synthesized by high-temperature co-precipitation of lanthanide chlorides in a high-boiling organic solvent (octadec-1-ene). The nanoparticles were coated with a thin shell (≈3 nm) of homogenous silica via the hydrolysis and condensation of tetramethyl orthosilicate. The NaYF4 :Yb3+ /Er3+ @SiO2 particles were further functionalized by methacrylate-terminated groups via 3-(trimethoxysilyl)propyl methacrylate. To introduce a large number of reactive amino groups on the particle surface, methacrylate-terminated NaYF4 :Yb3+ /Er3+ @SiO2 nanospheres were modified with a branched polyethyleneimine (PEI) via Michael addition. Aluminum carboxyphthalocyanine (Al Pc-COOH) was then conjugated to NaYF4 :Yb3+ /Er3+ @SiO2 -PEI nanospheres via carbodiimide chemistry. The resulting NaYF4 :Yb3+ /Er3+ @SiO2 -PEI-Pc particles were finally modified with succinimidyl ester of poly(ethylene glycol) (PEG) in order to alleviate their future uptake by the reticuloendothelial system. Upon 980 nm irradiation, the intensive red emission of NaYF4 :Yb3+ /Er3+ @SiO2 -PEI-Pc-PEG nanoparticles completely vanished, indicating efficient energy transfer from the nanoparticles to Al Pc-COOH, which generates singlet oxygen (1 O2 ). Last but not least, NaYF4 :Yb3+ /Er3+ @SiO2 -PEI-Pc-PEG nanospheres were intratumorally administered into mammary carcinoma MDA-MB-231 growing subcutaneously in athymic nude mice. Extensive necrosis developed at the tumor site of all mice 24-48 h after irradiation by laser at 980 nm wavelength. The results demonstrate that the NaYF4 :Yb3+ /Er3+ @SiO2 -PEI-Pc-PEG nanospheres have great potential as a novel NIR-triggered PDT nanoplatform for deep-tissue cancer therapy.

A Study for Sensitivity Improvement of 3‐D Lab‐on‐a‐CD‐Based Immunosensor

SUMMARYWe have developed a three‐dimensional (3D) Lab‐on‐a‐CD immunosensor based on a competitive/noncompetitive assay for small endocrine disruptors and biomolecules. To improve the sensitivity of the 3D Lab‐on‐a‐CD immunosensor, an immobilizing method of capturing‐type antibody on the sensor surface was investigated. The method is based on the introduction of a highly reactive amino group to a P(MMA/CEMA) copolymer surface having chlorine, and utilizing a biotin‐streptavidin system. The functionality of the 3D Lab‐on‐a‐CD immunosensor was evaluated by measuring mouse IgG. The detection limit was found to be 3 f g/assay (3 × 10‐12 g/assay). After further modification, the 3D Lab‐on‐a‐CD immunosensor, having some characteristics such as a substrate with highly integrated antibodies, is expected to be applicable for highly sensitive immunoassay.

Synthesis and characterization of hyperbranched polyimides from a novel B’B2-type triamine with tert-butyl side group

A novel triamine (1) with tert-butyl side group, N1,N1-bis(4-aminophenyl)-4-(tert-butyl)benzene-1,3-diamine, is synthesized and then polymerized with the dianhydride 6FDA (A2) at the different feed molar ratio. Monitoring by 1H NMR spectrum, the reactivity of 3-amino group with ortho-tert-butyl is much lower than that of 4′/4″-amino groups in triamine 1. Thus AB2-type amic acid (B’A2 intermediates) can be formed rapidly in situ when the polymerization is processed at 20 °C and the molar ratio of 1/6FDA is 1:2. Subsequently with increasing the polymerization temperature, 3-amino group with ortho-tert-butyl in AB2-type intermediates is activated and self-polycondensed with anhydride groups to produce hyperbranched polyimide (HBPI) without gelation. This indicates that it’s an effective approach to decrease the reactivity of amino groups in triamine by introducing tert-butyl into its ortho-position and HBPIs can be prepared conveniently through the method of ‘A2+B’B2′ based on the principle of unequal reactivity of functional groups.

Performance, carcass traits, meat quality and amino acid profile of different Japanese quails strains.

Poultry production is considered one of the prospective opportunities to accomplish sustainable and quick production of superior protein to challenge the growing mandate for animal protein. Therefore, this study was aimed to explore the difference on growth performance, carcass traits, meat quality and amino acid profile of different Japanese quails strains. A total of 480 quail chicks of four different plumage colors (120 of each white, golden, gray and brown) were collected after hatching. At 6week of age, birds were stunned and decapitated to determine the physical meat quality, thiobarbituric acid reactive substances and amino acid profile. White quails had the highest weight of slaughter, carcass, dressing, carcass yield, liver, gizzard, heart and spleen (197.27g, 169.27g, 91%, 82%, 6.63g, 6.53g, 2.27g and 0.40g, respectively). Also, they had the highest PhU, lightness, yellowness and water holding capacity with the lowest level of redness, cooking losses and thiobarbituric acid in pectoral (6.28, 46.40, 12,46, 22.17, 9.20, 19.21 and 0.44, respectively) and thigh muscles (6.37, 42.30, 11.51, 26.01, 10.12 and 0.93, respectively). Moreover, they possessed the highest level of all essential (11.68 and 10.16g/100g protein in pectoral and thigh muscles, respectively) and non essential amino acids (13.27 and 12.54g/100g protein in pectoral and thigh muscles, respectively). Therefore, the current study revealed that white quails had the heaviest body weight with the best carcass traits and meat quality.

Sequence-Based Prediction of Cysteine Reactivity Using Machine Learning

As one of the most intrinsically reactive amino acids, cysteine carries a variety of important biochemical functions, including catalysis and redox regulation. Discovery and characterization of cysteines with heightened reactivity will help annotate protein functions. Chemical proteomic methods have been used to quantitatively profile cysteine reactivity in native proteomes, showing a strong correlation between the chemical reactivity of a cysteine and its functionality; however, the relationship between the cysteine reactivity and its local sequence has not yet been systematically explored. Herein, we report a machine learning method, sbPCR (sequence-based prediction of cysteine reactivity), which combines the basic local alignment search tool, truncated composition of k-spaced amino acid pair analysis, and support vector machine to predict cysteines with hyper-reactivity based on only local sequence features. Using a benchmark set compiled from hyper-reactive cysteines in human proteomes, our method can achieve a prediction accuracy of 98%, a precision of 95%, and a recall ratio of 89%. We utilized these governing features of local sequence motifs to expand the prediction to potential hyper-reactive cysteines in other proteomes deposited in the UniProt database. We validated our predictions in Escherichia coli by activity-based protein profiling and discovered a hyper-reactive cysteine from a functionally uncharacterized protein, YecH. Biochemical analysis suggests that the hyper-reactive cysteine might be involved in metal binding. Our computational method provides a large inventory of potential hyper-reactive cysteines in proteomes and is highly complementary to other experimental approaches to guidesystematic annotation of protein functions in the postgenome era.

Characterization of Croatian Honeys by Right-Angle Fluorescence Spectroscopy and Chemometrics

The potential of right-angle fluorescence spectroscopy and selected chemical parameters for discrimination of botanical origin of Croatian honey types (n = 55) previously classified by physicochemical and melissopalynological analyses was evaluated. Systematic step-by-step fluorescence analysis included the measurement of complete excitation-emission matrix (EEM) in the range of excitation wavelengths from 260 to 400 nm, and emission wavelengths from 300 to 600 nm, followed by fluorescence intensity measurement at detected peaks of different excitation/emission wavelengths, and emission spectra recordings at selected specific excitation wavelengths of honey solutions in 50 mmol L−1 phosphate buffer pH 7.0 and methanol. A total of five different sets of emission spectral data for buffer and two for methanolic honey solutions were considered for chemometric analysis of original and normalized emission spectra including principal component analysis and linear discriminant analysis. Additionally, chemical analysis of buffer and methanolic honey solutions included determination of protein, total polyphenol and reactive amino group content. Results showed that right-angle fluorescence spectroscopy of honey solutions has great potential for honey botanical origin discrimination, either by visual comparison of excitation-emission spectra landscapes, or even better, by normalized emission fluorescence spectra recordings at 260 and 280 nm of excitation. Moreover, increased honey discrimination was achieved in conjunction with chemometrics of fluorescence spectras. In addition, two rapid markers/indicators of honey authentication were found. Chestnut honey could be clearly discriminated from the other honey types by simple measurement of fluorescence intensity at 390/470 nm, while sage honeys by measurement of reactive amino group content.

Human health risks from Chloramine-T use in food production and food processing industry: Co-induction of cytochrome P4504A1 and peroxisome proliferation

Although organic chloramines are known to form during the disinfection of drinking water with chlorine, little information is currently available on their occurrence or toxicity. In a recent in vitro study, some organic chloramines (e.g. N-chloroglycine) were found to be cytotoxic and genotoxic even at micromolar concentrations. In this paper, the formation and stability of 21 different organic chloramines, from chlorination of simple amines and amino acids, were studied, and the competition between 20 amino acids during chlorination was also investigated. For comparison, chlorination of two amides was also conducted. The formation and degradation of selected organic chloramines were measured using either direct UV spectroscopic or colorimetric detection. Although cysteine, methionine and tryptophan were the most reactive amino acids towards chlorination, they did not form organic chloramines at the chlorine to precursor molar ratios that were tested. Only 6 out of the 21 organic chloramines formed had a half-life of more than 3 h, although this group included all organic chloramines formed from amines. A health risk assessment relating stability and reactivity data from this study to toxicity and precursor abundance data from the literature indicated that only N-chloroglycine is likely to be of concern due to its stability, toxicity and abundance in water. However, given the stability of organic chloramines formed from amines, more information about the toxicity and precursor abundance for these chloramines is desirable.

Photocatalytic degradation of methylene blue dye over novel spherical mesoporous Cr2O3/TiO2 nanoparticles prepared by sol-gel using octadecylamine template

This research work demonstrate a facile, low cost and effective route for synthesis spherical mesoporous Cr2O3/TiO2 nanoparticles by sol-gel method and tailoring the particle structure using octadecylamine as structure and pore directing agent. X-ray diffraction [XRD], Fourier transformer infra-red [FTIR], N2-adsorption-desorption isotherm, Energy dispersive X-ray [EDX], High resolution transmission electron microscope [HRTEM] and Selected area electron diffraction [SAED] were selected to investigate the physicochemical features of the prepared nanoparticles. However, the photocatalytic reactivity was tested by following the photocatalytic degradation of methylene blue dye. Octadecylamine is an effective template with its reactive amino group is selected to manipulate nanoparticle structure with various mesoporous cavities that allow the diffusion the dye molecules. However, incorporation of chromium oxide is remarkably reduce the particle dimension, increase the surface area, create new mesoporous channels, the band gap energy of titania and limiting the electron-hole recombination. The positive synergetic effects of titania nanoparticles and chromium oxide including the electron transfer from titania conduction band to Cr2O3 energy levels was considered a primary cause for reduction in band gap energy and limiting the recombination of the charge carriers which enhance the oxidizing power for dye photodegradation. TOC and COD results indicate the removal of 90% of methylene blue dye into CO2 and H2O. The regeneration of the photocatalyst for 6-successsive repeated cycle indicating removal of 78% of wt after the six cycles revealing the high stability of the photocatalyst against corrosion upon expose to UV irradiations.

Mathematical modeling of CO 2 absorption into reactive DEAB solution in packed columns using surface-renewal penetration theory

Abstract In this work, a comprehensive model has been developed for CO2 absorption into 4-diethylamino-2-butanol (DEAB) as a reactive amino alcohol solution. The mathematical model is developed based on penetration theory by simultaneous considering of mass transfer phenomenon and chemical reactions. The penetration theory provides appropriate absorption rate and enhancement factor for the chemical absorption. A numerical analysis was performed to solve the applied partial differential equations for the liquid and gas phases simultaneously. The model results were validated using the available experimental data in literature. In this study, the absorption of carbon dioxide by monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), methyldiethanolamine (MDEA) and DEAB solutions was compared theoretically in a packed column absorber. The impact of parameters such as DEAB concentration, temperature, liquid flow rate, CO2 loading and CO2 partial pressure on the performance of a split-flow absorber have been examined. The modeling results indicated that the overall mass transfer coefficient (KGav) for CO2 absorption into DEAB solution was lower than MEA and DEA solutions, however much higher than MDEA and TEA solutions in all range of CO2 loading and partial pressure. Increasing the operating temperature, DEAB concentration and liquid flow rate enhanced the overall mass transfer coefficient.

Synthesis of Bifunctional Furano-Allocolchicinoids

An efficient seven-step semisynthetic approach towards non-racemic bifunctional furano-allocolchicinoids, starting from naturally occurring colchicine is presented. The Pd-catalyzed domino Sonogashira coupling/5-endo-dig cyclization was employed as the key step. The prepared compounds exhibited substantial cytotoxicity against T3M4, MiaPaCa-2, Colo-357, and PANC-1 cell lines. The presence of two functionalities with different reactivity (hydroxyl and amino groups) in the target molecules allows for an easy conjugation of furano-allocolchicinoids with drug delivery carriers, and opens promising opportunities for their further exploitation in the search of therapeutics.

Possible consequences of the sucrose replacement by a fructose-glucose syrup

The fructose-glucose syrup is currently used instead of sucrose in bakery products for economic and technological reasons. The authors investigated the extent to which this change affects the formation of non-enzymatic browning products (Advanced Glycation End - AGE-Products and melanoidins). Formation of these products in model systems - mixtures of various sugars (sucrose, fructose, glucose - concentration 6%) with glycine (concentration 0.7%) or/and lysine (concentration 0.3%), heat-treated 60 - 100 °C for 15, 30, 45 and 60 min, was studied. The formation of AGE products and melanoidins was determined on the basis of absorption at 294 nm (AGE-products) and 420 nm (melanoidins), respectively. The results pointed out notable difference in the AGE-products and also melanoidins formation for a variety of sugars. The reactivity of sucrose was low even at 100 °C/60 min. Fructose and glucose originated a significantly increasing of the non-enzymatic browning products formation. The reactivity of fructose was in the caramelisation and also in Maillard reactions the highest in any combination of composition. Lysine is the most reactive amino acid which takes part in Maillard reactions even if it is bound to protein. The non-enzymatic browning reactions result in the formation of non-digestible cross-linked proteins. Lysine is also the limiting essential amino acid of most cereals. Due to the lysine properties, reduction in protein quality is the most important nutritional effect of Maillard reactions in food. The sucrose replacement by fructose-glucose syrup in bakery products leads to more extensive non-enzymatic browning reactions, i.e. caramelisation and also Maillard reactions, while changes are in the Maillard reaction more pronounced.

Preparations of hyperbranched polymer nano micelles and the pH/redox controlled drug release behaviors

Hyperbranched polymer nano micelles (NMs) were prepared through a nucleophilic ring opening polymerization between cystamine and polyethylene glycol diglycidyl ether, followed by a reaction of amino groups and dimethyl maleic anhydride. The NMs showed spheric morphologies with hydrodynamic diameters of 106–120nm. Doxorubicin was loaded in the NMs with loading rate as high as 15.38wt%; The NMs possessed negative zeta potentials in aqueous solutions of pH7.4 due to the carboxyl ions on the particle surfaces, but the zeta potentials were converted to positive ones due to the hydrolysis of amide bonds at pH5.0–6.5, leading to the leaving of carboxyl groups and remaining of amino groups. The disulfide bonds in cystamine were designed in the hyperbranched polymer structures of the NMs, and bonds could be broken by a reducing agent l-glutathione (GSH) (10mM), resulting in a targeted drug release. The smart NMs displayed good biodegradability and biocompatibility, and they could be potentially used in drug controlled release field.

Facile Method for Fluorescent Labeling of Starch Nanocrystal

Fluorescently labeled starch nanocrystal (FL-SNC) was synthesized using a simple, low-cost, and scalable two-step chemical modification process. Reactive amino groups were introduced onto the SNC surface through silanization with 3-aminopropyl triethoxysilane (APTES), and fluorescein isothiocyanate (FITC) groups were covalently attached through thiourea. Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy, solid-state cross-polarization magic-angle spinning 13C NMR, UV–visible absorbance spectrophotometry, and fluorescence emission spectroscopy confirmed the successful introduction of the fluorescent groups. Transmission electron microscopy and X-ray diffraction data indicated that the dispersibility of FL-SNC was significantly improved, and the original crystallinity and morphology were retained. Compared with a mixture of uncoupled FITC and SNC, covalently connected FL-SNC displayed a more obvious fluorescence intensity and higher photostability. Furthermore, FL-SNC was biocompatib...

Fluorescent silica nanoparticles with chemically reactive surface: Controlling spatial distribution in one-step synthesis

The encapsulation of fluorescent dyes inside silica nanoparticles is advantageous to improve their quality as probes. Inside the particle, the fluorophore is protected from the external conditions and its main emission parameters remains unchanged even in the presence of quenchers. On the other hand, the amine-functionalized nanoparticle surface enables a wide range of applications, as amino groups could be easily linked with different biomolecules for targeting purposes. This kind of nanoparticle is regularly synthesized by methods that employ templates, additional nanoparticle formation or multiple pathway process. However, a one-step synthesis will be an efficient approach in this sort of bifunctional hybrid nanoparticles.A co-condensation sol-gel synthesis of hybrid fluorescent silica nanoparticle where developed. The chemical and morphological characterization of the particles where investigated by DRIFTS, XPS, SEM and SAXS. The nanoparticle fluorescent properties were also assessed by excitation-emission matrices and time resolved experiments.We have developed a one-pot synthesis method that enables the simultaneous incorporation of functionalities, the fluorescent molecule and the amino group, by controlling co-condensation process. An exhaustive characterization allows the definition of the spatial distribution of the fluorescent probe, fluorescein isothiocyanate, inside the particle and reactive amino groups on the surface of the nanoparticle with diameter about 100nm.

Reactive sites and course of reduction in the Rieske protein.

Rieske proteins play an essential role in electron transfer in the bc 1 complex. Rieske proteins contain a [2Fe-2S] cluster with one iron ligated by two histidines and the other iron ligated by two cysteines. All Rieske proteins have pH-dependent reduction potentials with the histidines ligating the cluster deprotonating in response to increases in pH. The addition of diethylpyrocarbonate (DEPC) modifies deprotonated histidines. The previous studies on the isolated Thermus thermophilus Rieske protein have used large excesses of DEPC, and this study examines what amino acids become modified under different molar equivalents of DEPC to protein. Increasing amounts of DEPC result in more modification, and higher pH values result in faster reaction. Upon modification, the protein also becomes reduced and ~6 equivalents of DEPC are needed for 50% of the reduction to occur. Which amino acids are modified first also points to the most reactive species on the protein. Mass spectrometry analysis shows that lysine 68 is the most reactive amino acid, followed by the ligating histidine 154 and two other surfaces lysines, 76 and 43. The modification of the ligating histidine at low numbers of DEPC equivalents and correlation with a similar number of equivalents needed to reduce the protein shows that this histidine can interact with neighboring groups, and these results can be extended to the protein within the bc 1 complex, where interaction with neighboring residues or molecules may allow reduction to occur. These results may shed light on how Rieske transfers electrons and protons in the bc 1 complex.

Protein Repair from Glycation by Glyoxals by the DJ-1 Family Maillard Deglycases.

DJ-1 and its prokaryotic homologs, Hsp31, YhbO and YajL from Escherichia coli and PfpI from Pyrococcus furiosus, repair proteins from glycation by glyoxals (R-CO-CHO), which constitute their major glycating agents. Glycation is a non-enzymatic covalent reaction discovered by Louis Camille Maillard in 1912, between reactive carbonyls (reducing sugars and glyoxals) and amino acids (cysteine, arginine and lysine), which inactivates proteins. By degrading Maillard adducts formed between carbonyls and thiols or amino groups, the DJ-1 family Maillard deglycases prevent the formation of the so-called advanced glycation end products (AGEs) that arise from Maillard adducts after dehydrations, oxidations and rearrangements. Since glycation is involved in ageing, cancer, atherosclerosis and cataracts, as well as post-diabetic, neurovegetatives and renal and autoimmune diseases, the DJ-1 deglycases are likely to play an important role in preventing these diseases. These deglycases, especially those from thermophilic organisms, may also be used to prevent the formation of dietary AGEs during food processing, sterilization and storage. They also prevent acrylamide formation in food, likely by degrading the asparagine/glyoxal Maillard adducts responsible for its formation. Since Maillard adducts are the substrates of the DJ-1 family deglycases, we propose renaming them Maillard deglycases.

Preparation of PEI/CS aerogel beads with a high density of reactive sites for efficient Cr(vi) sorption: batch and column studies

PEI/CS aerogel beads with a high density of reactive amino groups, with the aim of efficient Cr(vi) removal from aqueous solutions under column conditions, were easily preparedviacombinational yet controllable sol–gel and freeze drying processes.