Boron-doped sulfonated graphitic carbon nitride as a highly efficient catalyst for the production of 5-hydroxymethylfurfural from carbohydrates.

The presence of humins during the conversion of concentrated fructose presents a major obstacle in the large-scale production of 5-hydroxymethylfurfural (HMF) from fructose. Herein, we reported a boron-doped graphitic carbon nitride sulfonated (BGCN-SOH) as an excellent catalyst for the synthesis of HMF from fructose. The BGCN-SOH catalyst structures were analyzed using various characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDX), elemental mapping analysis, and Fourier-transform infrared spectroscopy (FT-IR).

The Safety and Feasibility of Ambulatory Minimally Invasive Partial Nephrectomy: A Systematic Review and Meta-Analysis.

Emerging evidence supports the use of minimally invasive partial nephrectomy (MIPN) in ambulatory settings. We conducted a systematic review and meta-analysis to evaluate differences in perioperative characteristics, complication/readmission rates and satisfaction/cost data between ambulatory and standard-length discharge (SLD) MIPN. This study was prospectively registered in PROSPERO (CRD42023429854).

One-Pot Effective Approach to 2,5-Diformylfuran From Carbohydrates Using MoS-Decorated Carbonaceous Sugarcane Bagasse.

Exploring the transformation of carbohydrates into valuable chemicals offers a promising and eco-friendly method for utilizing renewable biomass resources. Developing a bi-functional, sustainable heterogeneous catalyst is of utmost importance to attain a high level of selectivity for the desired product, 2,5-diformylfuran (DFF), in this direct conversion process. In this study, we developed a highly effective catalytic system to convert diverse carbohydrates into DFF.

Food Fingerprinting: Using a Two-Tiered approach to Monitor and Mitigate Food Fraud in Rice.

Background: Rice is an important staple food that is consumed around the world. Like many foods, the price of rice varies considerably, from very inexpensive for a low-quality product to premium pricing for highly prized varieties from specific locations. Therefore, like other foods it is vulnerable to economically motivated adulteration through substitution or misrepresentation of inferior-quality rice for more expensive varieties.

Computational design of protein-based inhibitors of Plasmodium vivax subtilisin-like 1 protease.

Background: Malaria remains a major global health concern. The development of novel therapeutic strategies is critical to overcome the selection of multiresistant parasites. The subtilisin-like protease (SUB1) involved in the egress of daughter Plasmodium parasites from infected erythrocytes and in their subsequent invasion into fresh erythrocytes has emerged as an interesting new drug target.

N-truncated Aβ peptides in complex fluids unraveled by new specific immunoassays.

Previous studies have highlighted the potential physiopathological and diagnostic role of N- and C-terminally truncated amyloid-β (Aβ) peptides in Alzheimer's disease. However, our knowledge about their production remains incomplete, in part due to the lack of very specific and sensitive tools for their detection. We thus developed specific monoclonal antibodies that target either Aβ11-x or Aβ17-x species, which result from the combined cleavages by β/γ- or α/γ-secretases, respectively.

Knottin cyclization: impact on structure and dynamics.

Background: Present in various species, the knottins (also referred to as inhibitor cystine knots) constitute a group of extremely stable miniproteins with a plethora of biological activities. Owing to their small size and their high stability, knottins are considered as excellent leads or scaffolds in drug design. Two knottin families contain macrocyclic compounds, namely the cyclotides and the squash inhibitors.

Cell-permeable peptide-based disruption of endogenous PKA-AKAP complexes: a tool for studying the molecular roles of AKAP-mediated PKA subcellular anchoring.

Stimulation of numerous G protein-coupled receptors leads to the elevation of intracellular concentrations of cAMP, which subsequently activates the PKA pathway. Specificity of the PKA signaling module is determined by a sophisticated subcellular targeting network that directs the spatiotemporal activation of the kinase. This specific compartmentalization mechanism occurs through high-affinity interactions of PKA with A-kinase anchoring proteins (AKAPs), the role of which is to target the kinase to discrete subcellular microdomains.

KNOTTIN: the knottin or inhibitor cystine knot scaffold in 2007.

The KNOTTIN database provides standardized information on the small disulfide-rich proteins with a knotted topology called knottins or inhibitor cystine knots. Static pages present the essential historical or recent results about knottin discoveries, sequences, structures, syntheses, folding, functions, applications and bibliography. New tools, KNOTER3D and KNOTER1D, are provided to determine or predict if a user query (3D structure or sequence) is a knottin.

Role of Asn(2) and Glu(7) residues in the oxidative folding and on the conformation of the N-terminal loop of apamin.

The X-ray structure of [N-acetyl]-apamin has been solved at 0.95 A resolution. It consists of an 1-7 N-terminal loop stabilized by an Asn-beta-turn motif (2-5 residues) and a helical structure spanning the 9-18 residues tightly linked together by two disulfide bonds.

Trypsin inhibition by macrocyclic and open-chain variants of the squash inhibitor MCoTI-II.

MCoTI-I and MCoTI-II from the seeds of Momordica cochinchinensis are inhibitors of trypsin-like proteases and the only known members of the large family of squash inhibitors that are cyclic and contain an additional loop connecting the amino- and the carboxy-terminus. To investigate the contribution of macrocycle formation to biological activity, we synthesized a set of open-chain variants of MCoTI-II that lack the cyclization loop and contain various natural and non-natural amino acid substitutions in the reactive-site loop. Upon replacement of P1 lysine residue #10 within the open-chain variant of MCoTI-II by the non-natural isosteric nucleo amino acid AlaG [beta-(guanin-9-yl)-L-alanine], a conformationally restricted arginine mimetic, residual inhibitory activity was detected, albeit reduced by four orders of magnitude.

Evaluation of lactoperoxidase system treatment to reduce anthracnose, stem-end rot, and bacterial black spot development during storage of mangoes.

The lactoperoxidase system (LPS) was evaluated for the prevention of postharvest diseases caused by Xanthomonas campestris, Botryodiplodia theobromae, and Colletotrichum gloeosporioides in 'Keitt' and 'Kent' mangoes. The LPS treatment significantly reduced the disease development on both cultivars after storage at 12 degrees C for 2 weeks, which was followed by a ripening at 25 degrees C. The LPS treatment did not alter the sensory quality of mango fruits (color, firmness, titrable acidity, and total soluble solids) when compared to untreated fruits.

Effect of the lactoperoxidase system against three major causal agents of disease in mangoes.

The antibacterial activity of the lactoperoxidase system (LPS) on the growth of Xanthomonas campestris, the causal agent of bacterial black spot in mangoes, Botryodiplodia theobromae, the causal agent of stem-end rot disease in mangoes, and Colletotrichum gloeosporioides, the causal agent of anthracnose disease in mangoes, was determined during culture at 30 degrees C and at several pH values (4.5, 5.5, and 6.

Contraction induced by glicentin on smooth muscle cells from the human colon is abolished by exendin (9-39).

Unlabelled: Glicentin and glucagon-like peptide-1 (7-36) amide (GLP-1) are gut hormones released during digestion. Glicentin and GLP-1 slow down gastric emptying and glicentin can switch off the duodenojejunal fed motor pattern. The effect of glicentin on the motor activity of colon has never been reported in humans.

Squash inhibitors: from structural motifs to macrocyclic knottins.

In this article, we will first introduce the squash inhibitor, a well established family of highly potent canonical serine proteinase inhibitors isolated from Cucurbitaceae. The squash inhibitors were among the first discovered proteins with the typical knottin fold shared by numerous peptides extracted from plants, animals and fungi. Knottins contain three knotted disulfide bridges, two of them arranged as a Cystine-Stabilized Beta-sheet motif.

Miniglucagon (MG)-generating endopeptidase, which processes glucagon into MG, is composed of N-arginine dibasic convertase and aminopeptidase B.

Miniglucagon (MG), the C-terminal glucagon fragment, processed from glucagon by the MG-generating endopeptidase (MGE) at the Arg17-Arg18 dibasic site, displays biological effects opposite to that of the mother-hormone. This secondary processing occurs in the glucagon- and MG-producing alpha-cells of the islets of Langerhans and from circulating glucagon. We first characterized the enzymatic activities of MGE in culture media from glucagon and MG-secreting alphaTC1.

Oxyntomodulin and glicentin are potent inhibitors of the fed motility pattern in small intestine.

Glicentin (GLIC) and oxyntomodulin (OXM or GLIC 33-69) are gut hormones which regulate digestion. They are known to reduce digestive secretions and to delay gastric emptying. Their biological activities on intestinal motility are still unknown.

The KNOTTIN website and database: a new information system dedicated to the knottin scaffold.

The KNOTTIN website and database organize information about knottins or inhibitor cystine knots, small disulfide-rich proteins with a knotted topology. Thanks to their small size and high stability, knottins provide appealing scaffolds for protein engineering and drug design. Static pages present the main historical and recent results about knottin discoveries, sequences, structures, folding, functions, applications and bibliography.

Miniglucagon (glucagon 19-29): a novel regulator of the pancreatic islet physiology.

Miniglucagon, the COOH-terminal (19-29) fragment processed from glucagon, is a potent and efficient inhibitor of insulin secretion from the MIN 6 beta-cell line. Using the rat isolated-perfused pancreas, we investigated the inhibitory effect of miniglucagon on insulin secretion and evaluated the existence of an inhibitory tone exerted by this peptide inside the islet. Miniglucagon dose-dependently inhibited insulin secretion stimulated by 8.

Solution structure of the squash trypsin inhibitor MCoTI-II. A new family for cyclic knottins.

The "knottin" fold is a stable cysteine-rich scaffold, in which one disulfide crosses the macrocycle made by two other disulfides and the connecting backbone segments. This scaffold is found in several protein families with no evolutionary relationships. In the past few years, several homologous peptides from the Rubiaceae and Violaceae families were shown to define a new structural family based on macrocyclic knottin fold.

Oxyntomodulin inhibits pancreatic secretion through the nervous system in rats.

Glicentin (GLIC), oxyntomodulin (OXM), and peptide YY (PYY) released in blood by ileocolonic L-cells after meals may inhibit pancreatic secretion. Whereas OXM interacts with glucagon and tGLP-1 receptors, OXM 19-37, a biologically active fragment, does not. The purpose of this study was to measure the effect of OXM, OXM 19-37, GLIC, tGLP-1, and PYY on pancreatic secretion stimulated by 2 deoxyglucose (2DG), electrical stimulation of the vagus nerves (VES), acetylcholine and cholecystokinin octapeptide (CCK8) in anesthetized rats.

Squash trypsin inhibitors from Momordica cochinchinensis exhibit an atypical macrocyclic structure.

Three trypsin inhibitors (TIs), from the seeds of the squash Momordica cochinchinensis (MCo), have been isolated and purified using gel filtration, ion exchange chromatography, and reverse-phase HPLC. Their sequences could be determined only after proteolytic cleavages. In the case of MCoTI-I and -II, it was shown that their polypeptide backbones are cyclic, a structure that has never been described in squash TIs.

Min-21 and min-23, the smallest peptides that fold like a cystine-stabilized beta-sheet motif: design, solution structure, and thermal stability.

Small disulfide-rich proteins provide examples of simple and stable scaffolds for design purposes. The cystine-stabilized beta-sheet (CSB) motif is one such elementary structural motif and is found in many protein families with no evolutionary relationships. In this paper, we present NMR structural studies and stability measurements of two short peptides of 21 and 23 residues that correspond to the isolated CSB motif taken from a 28-residue squash trypsin inhibitor.