Effective adsorption of Pb(II) ion from aqueous solution onto ZSM-5 zeolite synthesized from Vietnamese bentonite clay.

ZSM-5 zeolite was successfully synthesized from bentonite clay sourced from Lam Dong Province, Vietnam, using the hydrothermal method at 170 °C for 18 h. The synthesized ZSM-5 (SiO/AlO ratio ~ 34) exhibited a single phase with high crystallinity (91.8%), and a clear and uniform shape.

Kinetic studies of the removal of methylene blue from aqueous solution by biochar derived from jackfruit peel.

Kinetic studies play an instrumental role in determining the most appropriate reaction rate model for industrial-scale applications. This study focuses on the kinetics of methylene blue (MB) adsorption from aqueous solutions by biochar derived from jackfruit peel. Various kinetic models, including pseudo-first-order (PFO), pseudo-second-order (PSO), intra-diffusion, and Elovich models, were applied to study MB adsorption kinetics of jackfruit peel biochar.

The effective Ni(II) removal of red mud modified chitosan from aqueous solution.

This study used red mud modified with chitosan (RM/CS) as a novel adsorbent to remove Ni(II) ions from an aqueous solution. The adsorbent was characterized by the techniques of the BET method, X-ray diffraction (XRD), and scanning electron microscopy (SEM) analysis. According to the findings, the surface area of RM/CS is nearly doubled compared to CS, from 68.

Crystallization Pathways and Evolution of Morphologies and Structural Defects of α-MnO under Air Annealing.

Manganese dioxide nanomaterials have wide applications in many areas from catalysis and Li-ion batteries to gas sensing. Understanding the crystallization pathways, morphologies, and formation of defects in their structure is particularly important but still a challenging issue. Herein, we employed an arsenal of X-ray diffraction (XRD), scanning electron microscopy (SEM), neutron diffraction, positron annihilation spectroscopies, and calculations to investigate the evolution of the morphology and structure of α-MnO nanomaterials prepared via reduction of KMnO solution with CHOH prior to being annealed in air at 200-600 °C.

Pb(II) adsorption mechanism and capability from aqueous solution using red mud modified by chitosan.

Red mud modified by chitosan (RM/CS) was utilized as an adsorbent to effectively remove Pb(II) from aqueous solution. The surface area of RM/CS was found to significantly increase by more than 50% compared to that of original red mud. Different factors that affected the Pb(II) removal on this material, such as initial Pb(II) concentration, pH, and contact time, were investigated.

Fructuronate-tagaturonate epimerase UxaE from Cohnella laeviribosi has a versatile TIM-barrel scaffold suitable for a sugar metabolizing biocatalyst.

Xylan and pectin are major structural components of plant cell walls. There are two independent catabolic pathways for xylan and pectin. UxaE bridges these two pathways by reversibly epimerizing D-fructuronate and D-tagaturonate.

Chitosan-MnO nanocomposite for effective removal of Cr (VI) from aqueous solution.

In this report, the adsorption of Cr(VI) onto MnO/CS nanocomposite material from aqueous solution is investigated. All the factors, which affect the adsorption, such as pH, adsorption time, Cr(VI) initial concentration and adsorbent dosage, are also examined. The results obtained show that the Cr(VI) uptake is strongly affected by pH and ion strength.

Inhibitory effect of α-terpinyl acetate on cytochrome P450 2B6 enzymatic activity.

Human cytochrome P450 2B6 is an important hepatic enzyme for the metabolism of xenobiotics and clinical drugs. Recently, more attention has been paid to P450 2B6 because of the increasing number of drugs it metabolizes. It has been known to interact with terpenes, the major constituents of the essential oils used for various medicinal purposes.

Crystal structures of an atypical aldehyde dehydrogenase having bidirectional oxidizing and reducing activities.

Aldehyde dehydrogenases (ALDHs) are NAD(P)-dependent oxidoreductases that catalyze the oxidation of a variety of aldehydes to their acid forms. In this study, we determined the crystal structures of ALDH from Bacillus cereus (BcALDH), alone, and in complex with NAD and NADP. This enzyme can oxidize all-trans-retinal to all-trans-retinoic acid using either NAD or NADP with equal efficiency, and atypically, as a minor activity, can reduce all-trans-retinal to all-trans-retinol using NADPH.

Catalytic Intermediate Crystal Structures of Cysteine Desulfurase from the Archaeon NA1.

NA1 is an anaerobic archaeon usually found in a deep-sea hydrothermal vent area, which can use elemental sulfur (S) as a terminal electron acceptor for energy. Sulfur, essential to many biomolecules such as sulfur-containing amino acids and cofactors including iron-sulfur cluster, is usually mobilized from cysteine by the pyridoxal 5'-phosphate- (PLP-) dependent enzyme of cysteine desulfurase (CDS). We determined the crystal structures of CDS from NA1 (ToCDS), which include native internal aldimine (NAT), gem-diamine (GD) with alanine, internal aldimine structure with existing alanine (IAA), and internal aldimine with persulfide-bound Cys356 (PSF) structures.

Improvement of enzyme activity of β-1,3-1,4-glucanase from Paenibacillus sp. X4 by error-prone PCR and structural insights of mutated residues.

β-1,3-1,4-Glucanase (BGlc8H) from Paenibacillus sp. X4 was mutated by error-prone PCR or truncated using termination primers to improve its enzyme properties. The crystal structure of BGlc8H was determined at a resolution of 1.

Crystallographic snapshots of active site metal shift in E. coli fructose 1,6-bisphosphate aldolase.

Fructose 1,6-bisphosphate aldolase (FBA) is important for both glycolysis and gluconeogenesis in life. Class II (zinc dependent) FBA is an attractive target for the development of antibiotics against protozoa, bacteria, and fungi, and is also widely used to produce various high-value stereoisomers in the chemical and pharmaceutical industry. In this study, the crystal structures of class II Escherichia coli FBA (EcFBA) were determined from four different crystals, with resolutions between 1.

Crystal Structures of Peptide Deformylase from Rice Pathogen Xanthomonas oryzae pv. oryzae in Complex with Substrate Peptides, Actinonin, and Fragment Chemical Compounds.

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight on rice; this species is one of the most destructive pathogenic bacteria in rice cultivation worldwide. Peptide deformylase (PDF) catalyzes the removal of the N-formyl group from the N-terminus of newly synthesized polypeptides in bacterial cells and is an important target to develop antibacterial agents.

Expression, crystallization and preliminary X-ray crystallographic analysis of DNA-directed RNA polymerase subunit L from Thermococcus onnurineus NA1.

RNA polymerase (RNAP) plays a crucial role in gene expression in all organisms. It is a multiprotein complex that produces primary transcript RNA. Generally, the basal transcription apparatus in archaea is simpler than the eukaryotic RNA polymerase II counterpart.