Feruloyl esterases (FAEs) are a crucial component of the hemicellulose-degrading enzyme family that facilitates the degradation of lignocellulose while releasing hydroxycinnamic acids such as ferulic acid with high added value. Currently, the low enzyme yield of FAEs is one of the primary factors limiting its application. Therefore, in this paper, we optimized the fermentation conditions for the expression of FAE BpFaeT132C-D143C with excellent thermal stability in Escherichia coli by experimental design. Firstly, we explored the effects of 11 factors such as medium type, isopropyl-β-D-thiogalactopyranoside (IPTG) concentration, and inoculum size on BpFaeT132C-D143C activity separately by the single factor design. Then, the significance of the effects of seven factors, such as post-induction temperature, shaker rotational speed, and inoculum size on BpFaeT132C-D143C activity, was analyzed by Plackett-Burman design. We identified the main factors affecting the fermentation conditions of E. coli expressing BpFaeT132C-D143C as post-induction temperature, pre-induction period, and post-induction period. Finally, we used the steepest ascent path design and response surface method to optimize the levels of these three factors further. Under the optimal conditions, the activity of BpFaeT132C-D143C was 3.58 U/ml, which was a significant 6.6-fold increase compared to the pre-optimization (0.47 U/ml), demonstrating the effectiveness of this optimization process. Moreover, BpFaeT132C-D143C activity was 1.52 U/ml in a 3-l fermenter under the abovementioned optimal conditions. It was determined that the expression of BpFaeT132C-D143C in E. coli was predominantly intracellular in the cytoplasm. This study lays the foundation for further research on BpFaeT132C-D143C in degrading agricultural waste transformation applications.
- MeSH
- Escherichia coli * genetics metabolism enzymology MeSH
- Fermentation * MeSH
- Isopropyl Thiogalactoside metabolism MeSH
- Carboxylic Ester Hydrolases * genetics metabolism chemistry biosynthesis MeSH
- Culture Media chemistry MeSH
- Coumaric Acids metabolism MeSH
- Lignin MeSH
- Recombinant Proteins genetics metabolism biosynthesis chemistry MeSH
- Enzyme Stability MeSH
- Temperature MeSH
- Publication type
- Journal Article MeSH
L-asparaginase is an essential enzyme used in cancer treatment, but its production faces challenges like low yield, high cost, and immunogenicity. Recombinant production is a promising method to overcome these limitations. In this study, response surface methodology (RSM) was used to optimize the production of L-asparaginase 1 from Saccharomyces cerevisiae in Escherichia coli K-12 BW25113. The Box-Behnken design (BBD) was utilized for the RSM modeling, and a total of 29 experiments were conducted. These experiments aimed to examine the impact of different factors, including the concentration of isopropyl-b-LD-thiogalactopyranoside (IPTG), the cell density prior to induction, the duration of induction, and the temperature, on the expression level of L-asparaginase 1. The results revealed that while the post-induction temperature, cell density at induction time, and post-induction time all had a significant influence on the response, the post-induction time exhibited the greatest effect. The optimized conditions (induction at cell density 0.8 with 0.7 mM IPTG for 4 h at 30 °C) resulted in a significant amount of L-asparaginase with a titer of 93.52 μg/mL, which was consistent with the model-based prediction. The study concluded that RSM optimization effectively increased the production of L-asparaginase 1 in E. coli, which could have the potential for large-scale fermentation. Further research can explore using other host cells, optimizing the fermentation process, and examining the effect of other variables to increase production.
- MeSH
- Asparaginase * genetics biosynthesis metabolism MeSH
- Escherichia coli K12 genetics enzymology MeSH
- Escherichia coli genetics metabolism MeSH
- Fermentation MeSH
- Isopropyl Thiogalactoside pharmacology MeSH
- Recombinant Proteins * genetics metabolism MeSH
- Saccharomyces cerevisiae * genetics metabolism MeSH
- Temperature MeSH
- Publication type
- Journal Article MeSH
The binding of human galectins by glycomimetic inhibitors is a promising therapeutic approach. The structurally distinct group of tandem-repeat galectins has scarcely been studied so far, and there is hardly any knowledge on their ligand specificity or their inhibitory potential, particularly concerning non-natural carbohydrates. Here, we present the synthesis of a library of seven 3-O-disubstituted thiodigalactoside-derived glycomimetics and their affinity to two tandem-repeat galectins, Gal-8 and Gal-9. The straightforward synthesis of these glycomimetics involved dibutyltin oxide-catalyzed 3,3́-O-disubstitution of commercially available unprotected thiodigalactoside, and conjugation of various aryl substituents by copper-catalyzed Huisgen azide-alkyne cycloaddition (CuAAC). The inhibitory potential of the prepared glycomimetics for Gal-8 and Gal-9 was assessed, and compared with the established galectins Gal-1 and Gal-3. The introduction of C-3 substituents resulted in an over 40-fold increase in affinity compared with unmodified TDG. The structure-affinity relations within the studied series were discussed using molecular modeling. Furthermore, the prepared glycomimetics were shown to scavenge Gal-8 and Gal-9 from the surface of cancer cells. This pioneering study on the synthetic inhibitors especially of Gal-9 identified lead compounds that may be used in further biomedical research.
- MeSH
- Galectins * metabolism MeSH
- Humans MeSH
- Carbohydrates chemistry MeSH
- Thiogalactosides * chemistry MeSH
- Protein Binding MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Galectin-3 (Gal-3) participates in many cancer-related metabolic processes. The inhibition of overexpressed Gal-3 by, e.g., β-galactoside-derived inhibitors is hence promising for cancer treatment. The multivalent presentation of such inhibitors on a suitable biocompatible carrier can enhance the overall affinity to Gal-3 and favorably modify the interaction with Gal-3-overexpressing cells. We synthesized a library of C-3 aryl-substituted thiodigalactoside inhibitors and their multivalent N-(2-hydroxypropyl)methacrylamide (HPMA)-based counterparts with two different glycomimetic contents. Glycopolymers with a higher content of glycomimetic exhibited a higher affinity to Gal-3 as assessed by ELISA and biolayer interferometry. Among them, four candidates (with 4-acetophenyl, 4-cyanophenyl, 4-fluorophenyl, and thiophen-3-yl substitution) were selected for further evaluation in cancer-related experiments in cell cultures. These glycopolymers inhibited Gal-3-induced processes in cancer cells. The cyanophenyl-substituted glycopolymer exhibited the strongest antiproliferative, antimigratory, antiangiogenic, and immunoprotective properties. The prepared glycopolymers appear to be prospective modulators of the tumor microenvironment applicable in the therapy of Gal-3-associated cancers.
The site-specific chemical modification of proteins through incorporation of noncanonical amino acids enables diverse applications, such as imaging, probing, and expanding protein functions, as well as to precisely engineer therapeutics. Here we report a general strategy that allows the incorporation of noncanonical amino acids into target proteins using the amber suppression method and their efficient secretion in the biotechnological relevant expression host Bacillus subtilis. This facilitates efficient purification of target proteins directly from the supernatant, followed by their functionalization using click chemistry. We used this strategy to site-specifically introduce norbornene lysine into a single chain antibody and functionalize it with fluorophores for the detection of human target proteins.
- MeSH
- Bacillus subtilis genetics metabolism MeSH
- Click Chemistry MeSH
- CRISPR-Cas Systems MeSH
- Enzyme-Linked Immunosorbent Assay MeSH
- Genetic Vectors MeSH
- Genetic Code MeSH
- Isopropyl Thiogalactoside pharmacology MeSH
- Creatine Kinase, MM Form metabolism MeSH
- Humans MeSH
- Lysine chemistry MeSH
- Norbornanes chemistry MeSH
- Protein Engineering methods MeSH
- Gene Expression Regulation, Bacterial drug effects MeSH
- Recombinant Proteins chemistry genetics isolation & purification metabolism MeSH
- Green Fluorescent Proteins genetics metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
PURPOSE: To study new skin penetration/permeation enhancers based on amphiphilic galactose derivatives. METHODS: Two series of alkyl and alkenyl galactosides were synthesized and evaluated for their enhancing effect on transdermal/topical delivery of theophylline (TH), hydrocortisone (HC) and cidofovir (CDV), reversibility of their effects on transepidermal water loss (TEWL) and skin impedance, interaction with the stratum corneum using infrared spectroscopy, and cytotoxicity on keratinocytes and fibroblasts. RESULTS: Initial evaluation identified 1-(α-D-galactopyranosyl)-(2E)-pentadec-2-ene A15 as a highly potent enhancer - it increased TH and HC flux through human skin 8.5 and 5 times, respectively. Compound A15 increased the epidermal concentration of a potent antiviral CDV 7 times over that reached by control and Span 20 (an established sugar-based enhancer). Infrared spectroscopy of human stratum corneum indicated interaction of A15 with skin barrier lipids but not proteins. These effects of A15 on the skin barrier were reversible (both TEWL and skin impedance returned to baseline values within 24 h after A15 had been removed from skin). In vitro toxicity of A15 on HaCaT keratinocytes and 3T3 fibroblasts was acceptable, with IC50 values over 60 μM. CONCLUSIONS: Galactosyl pentadecene A15 is a potent enhancer with low toxicity and reversible action.
- MeSH
- Alkenes administration & dosage chemistry MeSH
- Administration, Cutaneous MeSH
- Cytosine administration & dosage analogs & derivatives chemistry MeSH
- Epidermis metabolism MeSH
- Fibroblasts drug effects metabolism MeSH
- Galactose analogs & derivatives chemistry MeSH
- Galactosides administration & dosage chemistry MeSH
- Hydrocortisone administration & dosage chemistry MeSH
- Keratinocytes drug effects metabolism MeSH
- Skin Absorption drug effects MeSH
- Skin metabolism MeSH
- Humans MeSH
- Lipids chemistry MeSH
- Organophosphonates administration & dosage chemistry MeSH
- Permeability MeSH
- Theophylline administration & dosage chemistry MeSH
- Drug Liberation MeSH
- Water MeSH
- Structure-Activity Relationship MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: Heterologous expression systems based on promoters inducible with isopropyl-β-D-1-thiogalactopyranoside (IPTG), e.g., Escherichia coli BL21(DE3) and cognate LacI(Q)/P(lacUV5)-T7 vectors, are commonly used for production of recombinant proteins and metabolic pathways. The applicability of such cell factories is limited by the complex physiological burden imposed by overexpression of the exogenous genes during a bioprocess. This burden originates from a combination of stresses that may include competition for the expression machinery, side-reactions due to the activity of the recombinant proteins, or the toxicity of their substrates, products and intermediates. However, the physiological impact of IPTG-induced conditional expression on the recombinant host under such harsh conditions is often overlooked. RESULTS: The physiological responses to IPTG of the E. coli BL21(DE3) strain and three different recombinants carrying a synthetic metabolic pathway for biodegradation of the toxic anthropogenic pollutant 1,2,3-trichloropropane (TCP) were investigated using plating, flow cytometry, and electron microscopy. Collected data revealed unexpected negative synergistic effect of inducer of the expression system and toxic substrate resulting in pronounced physiological stress. Replacing IPTG with the natural sugar effector lactose greatly reduced such stress, demonstrating that the effect was due to the original inducer's chemical properties. CONCLUSIONS: IPTG is not an innocuous inducer; instead, it exacerbates the toxicity of haloalkane substrate and causes appreciable damage to the E. coli BL21(DE3) host, which is already bearing a metabolic burden due to its content of plasmids carrying the genes of the synthetic metabolic pathway. The concentration of IPTG can be effectively tuned to mitigate this negative effect. Importantly, we show that induction with lactose, the natural inducer of P lac , dramatically lightens the burden without reducing the efficiency of the synthetic TCP degradation pathway. This suggests that lactose may be a better inducer than IPTG for the expression of heterologous pathways in E. coli BL21(DE3).
Chromatin compaction mediates progenitor to post-mitotic cell transitions and modulates gene expression programs, yet the mechanisms are poorly defined. Snf2h and Snf2l are ATP-dependent chromatin remodelling proteins that assemble, reposition and space nucleosomes, and are robustly expressed in the brain. Here we show that mice conditionally inactivated for Snf2h in neural progenitors have reduced levels of histone H1 and H2A variants that compromise chromatin fluidity and transcriptional programs within the developing cerebellum. Disorganized chromatin limits Purkinje and granule neuron progenitor expansion, resulting in abnormal post-natal foliation, while deregulated transcriptional programs contribute to altered neural maturation, motor dysfunction and death. However, mice survive to young adulthood, in part from Snf2l compensation that restores Engrailed-1 expression. Similarly, Purkinje-specific Snf2h ablation affects chromatin ultrastructure and dendritic arborization, but alters cognitive skills rather than motor control. Our studies reveal that Snf2h controls chromatin organization and histone H1 dynamics for the establishment of gene expression programs underlying cerebellar morphogenesis and neural maturation.
- MeSH
- Adenosine Triphosphatases metabolism MeSH
- Analysis of Variance MeSH
- Bromodeoxyuridine MeSH
- Chromatin Immunoprecipitation MeSH
- Chromosomal Proteins, Non-Histone metabolism MeSH
- Fluorescence MeSH
- Galactosides MeSH
- Histones metabolism MeSH
- Homeodomain Proteins metabolism MeSH
- In Situ Hybridization MeSH
- Immunohistochemistry MeSH
- Indoles MeSH
- In Situ Nick-End Labeling MeSH
- Real-Time Polymerase Chain Reaction MeSH
- Rotarod Performance Test MeSH
- Microarray Analysis MeSH
- Morphogenesis genetics physiology MeSH
- Cerebellum embryology MeSH
- Mice, Transgenic MeSH
- Mice MeSH
- Neural Stem Cells metabolism physiology MeSH
- Image Processing, Computer-Assisted MeSH
- Reverse Transcriptase Polymerase Chain Reaction MeSH
- Purkinje Cells metabolism MeSH
- Chromatin Assembly and Disassembly physiology MeSH
- Tolonium Chloride MeSH
- Microscopy, Electron, Transmission MeSH
- Gene Expression Regulation, Developmental genetics physiology MeSH
- Blotting, Western MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Mice MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, N.I.H., Extramural MeSH
The antiurease activity of the aqueous extracts of 42 plants growing in the Czech Republic was investigated. A phenol-hypochlorite reaction was used for the determination of ammonia produced by urease. The inhibitory activity of the extracts at a concentration of 0.2 mg/mL varied from 17.8% to 80.0%. Extracts from six Potentilla species expressed inhibitory activity against jack bean urease. They were further investigated for their phenolic constituents and the major compounds were subjected to molecular docking. The results revealed that both jack bean urease and Helicobacter pylori urease were inhibited by quercetin-3-O-β-D-galactopyranoside-6″-gallate (1), myricetin-3-O-β-D-glucuronide (2), tiliroside (3) and B-type procyanidin (4). The antiurease activity of the investigated Potentilla species is probably due to the presence of complex phenolic constituents such as flavonoid glycosides and catechin dimers.
- MeSH
- Algorithms MeSH
- Canavalia enzymology MeSH
- Phenols chemistry isolation & purification pharmacology MeSH
- Flavonoids chemistry isolation & purification pharmacology MeSH
- Galactosides chemistry isolation & purification pharmacology MeSH
- Helicobacter pylori drug effects MeSH
- Helicobacter Infections drug therapy MeSH
- Plants, Medicinal chemistry MeSH
- Potentilla chemistry MeSH
- Quercetin analogs & derivatives MeSH
- Urease antagonists & inhibitors MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Czech Republic MeSH
Invazívne mykotické infekcie predstavujú závažnú infekčnú komplikáciu imunokompromitovaných pacientov. V porovnaní s bakteriálnymi infekciami je ich výskyt menej častý, na druhú stranu mortalita s nimi spojená je výrazne vyššia než je tomu u infekcií bakteriálnych. Posledné dve desaťročia priniesli významné zmeny v epidemiológii invazívnych mykóz a behom posledných niekoľkých rokov došlo k značným pokrokom v diagnostike a liečbe.
Invasive fungal infections are serious life-threatening complication in immunocompromised patients. They are rare in comparison with bacterial infection but attributable mortality is higher. Last two decades brought significant changes in epidemiology of invasive fungal diseases and the last few years brought much progress in diagnostics and treatment.
- MeSH
- Antigens, Fungal analysis MeSH
- Aspergillosis etiology pathology transmission MeSH
- beta-Glucans diagnostic use MeSH
- Candida classification pathogenicity growth & development MeSH
- Diagnostic Techniques and Procedures MeSH
- Diagnosis, Differential MeSH
- Galactosides diagnostic use MeSH
- Hematologic Neoplasms * immunology complications MeSH
- Immunosuppression Therapy adverse effects MeSH
- Candidiasis, Invasive diagnosis etiology therapy MeSH
- Humans MeSH
- Mannans diagnostic use blood MeSH
- Mycoses * diagnosis epidemiology mortality therapy MeSH
- Opportunistic Infections diagnosis complications MeSH
- Rhizomucor pathogenicity MeSH
- Risk Factors MeSH
- Sensitivity and Specificity MeSH
- Zygomycosis diagnosis etiology therapy MeSH
- Check Tag
- Humans MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
