This study aims to delve into the influences and underlying mechanisms of Banxia Xiexin Decoction(BXD) on the proliferation, apoptosis, invasion, and migration of colon cancer cells. Firstly, the components of BXD in blood were identified by UPLC-MS/MS, and subsequently the content of these components were determined by HPLC. Then, different concentrations of BXD were used to treat both the normal intestinal epithelial cells(NCM460) and the colon cancer cells(HT29 and HCT116). The cell viability and apoptosis were examined by the cell counting kit-8(CCK-8) and flow cytometry, respectively. Western blot was employed to determine the expression of the apoptosis regulators B-cell lymphoma-2(Bcl-2) and Bcl-2-associated X(Bax). The cell wound healing assay and Transwell assay were employed to measure the cell migration and invasion, respectively. Additionally, Western blot was employed to determine the expression levels of epithelial-mesenchymal transition(EMT)-associated proteins, including epithelial cadherin(E-cadherin), neural cadherin(N-cadherin), and vimentin. The protein and mRNA levels of the factors in the poly(ADP-ribose) glycohydrolase(PARG)/poly(ADP-ribose) polymerase 1(PARP1)/nuclear factor kappa-B p65(NF-κB p65) signaling pathway were determined by Western blot and RT-qPCR, respectively. The results demonstrated that following BXD intervention, the proliferation of HT29 and HCT116 cells was significantly reduced. Furthermore, BXD promoted the apoptosis, enhanced the expression of Bcl-2, and suppressed the expression of Bax in colon cancer cells. At the same time, BXD suppressed the cell migration and invasion and augmented the expression of E-cadherin while diminishing the expression of N-cadherin and vimentin. In addition, BXD down-regulated the protein and mRNA levels of PARG, PARP1, and NF-κB p65. In conclusion, BXD may inhibit the malignant phenotypes of colon cancer cells by mediating the PARG/PARP1/NF-κB signaling pathway.
Colonic Neoplasms/pathology* ; Drugs, Chinese Herbal/pharmacology* ; Phenotype ; Signal Transduction/drug effects* ; Cell Proliferation/drug effects* ; Apoptosis ; Cell Movement/drug effects* ; Neoplasm Invasiveness ; HCT116 Cells ; Proto-Oncogene Proteins c-bcl-2/biosynthesis* ; Humans ; Poly (ADP-Ribose) Polymerase-1 ; Glycoside Hydrolases ; bcl-2-Associated X Protein ; NF-kappa B p50 Subunit

To screen and identify a chitosanase with high stability, we cloned the chitosanase gene from Bacillus atrophaeus with a high protease yield from the barren saline-alkali soil and expressed this gene in Escherichia coli. The expressed chitosanase of B. atrophaeus (BA-CSN) was purified by nickel-affinity column chromatography. The properties including optimal temperature, optimal pH, substrate specificity, and kinetic parameters of BA-CSN were characterized. The results showed that BA-CSN had the molecular weight of 31.13 kDa, the optimal temperature of 55 ℃, the optimal pH 5.5, and good stability at temperatures below 45 ℃ and pH 4.0-9.0. BA-CSN also had good stability within 4 h of pH 3.0 and 10.0, be activated by K⁺, Na⁺, Mn²⁺, Ca²⁺, Mg²⁺, and Co²⁺, (especially by Mn²⁺), and be inhibited by Fe³⁺, Cu²⁺, and Ag⁺. BA-CSN showcased the highest relative activity in the hydrolysis of colloidal chitosan, and it had good hydrolysis ability for colloidal chitin. Under the optimal catalytic conditions, BA-CSN demonstrated the Michaelis constant K_m and maximum reaction rate V_max of 9.94 mg/mL and 26.624 μmoL/(mL·min), respectively, for colloidal chitosan. In short, BA-CSN has strong tolerance to acids and alkali, possessing broad industrial application prospects.
Bacillus/genetics* ; Hydrogen-Ion Concentration ; Escherichia coli/metabolism* ; Glycoside Hydrolases/biosynthesis* ; Substrate Specificity ; Enzyme Stability ; Chitosan/metabolism* ; Temperature ; Kinetics ; Cloning, Molecular ; Bacterial Proteins/biosynthesis* ; Recombinant Proteins/genetics*

Glycoside compounds are widely used in medicine, food, surfactant, and cosmetics. The glycosidase-catalyzed synthesis of glycoside can be operated at mild reaction conditions with low material cost. The glycosidase-catalyzed processes include reverse hydrolysis and transglycosylation, appropriately reducing the water activity in both processes may effectively improve the catalytic efficiency of glucosidase. However, glucosidase is prone to be deactivated at low water activity. Thus, glucosidase was immobilized to maintain its activity in the low water activity environment, and even in neat organic solvent system. This article summarizes the advances in glycosidase immobilization in the past 30 years, including single or comprehensive immobilization techniques, and immobilization techniques combined with genetic engineering, with the aim to provide a reference for the synthesis of glycosides using immobilized glycosidases.
Catalysis ; Enzymes, Immobilized ; Glycoside Hydrolases/genetics* ; Glycosides/biosynthesis* ; Hydrolysis

The xylanolytic enzymes found in Thermotoga maritima showed extremely high thermostability and considerable potential in industrial application. Yet expression level of the genes encoding these enzymes was very low. The alpha-glucuronidase gene aguA from T. maritima ATCC 43589 was cloned and expressed in several E. coli strains with different vector. The alpha-glucuronidase was overexpressed in E. coli BL21-CodonPlus(DE3)-RIL with plasmid pET-28a(+), and made up about 20% of the total proteins present in the intracellular soluble fraction. The results proved the assumption that rare codons for arginine (AGA/AGG) and isoleucine (AUA) affect the expression of aguA gene from hyperthermophilic bacterium T. maritima in E. coli. Purification procedure included two steps, heat treatment and immobilized metal affinity chromatography, and over 13.5mg of pure enzyme was obrained from 1L of induced culture. The purified enzyme showed a single band on SDS polyacrylamide gel electrophoresis with a purification of 5.1 fold, and a yield of 55.1%. The optimum activity of recombinant alpha-glucuronidase was found at pH 6.0 and 85 degrees C, the enzyme retained 70% of its activity after 1 h of incubation at 85 degrees C. The induction conditions for expression of recombinant strain BL21-CodonPlus(DE3)-RIL/pET-28a-aguA were studied on induction time and duration by IPTG. The results showed that the activity of thermostable alpha-glucuronidase reach the maximum in 5-hour after inducted at the exponential phase (OD600 of 0.7 - 0.8).
Escherichia coli ; genetics ; Glycoside Hydrolases ; genetics ; isolation & purification ; metabolism ; Plasmids ; Recombinant Proteins ; biosynthesis ; isolation & purification ; Thermotoga maritima ; enzymology

The gene coding for beta-glycosidase (EC3.2.1.21) from Thermus nonproteolyticus HG102 has been cloned and expressed in E. coli. The gene open reading frame was 1311 bp and it codes for 436 amino acids. The deduced amino acid sequence of the enzyme showed identity with members of glycosyl hydrolase family I. The enzyme had high content of hydrophobic amino acid (Ala 12.8%, Leu 10.9%), Arg(9.6%), Glu(9.4%) and Pro(8.0%), but low content Cys(0.45%) and Met (0.9%). From the alignment of enzyme amino acid sequence with other glycosyl hydrolase family I members, Glu164 and Glu338 were predicated as the proton donor and nucleophile group. The DNASTAR program was used to predict the secondary structure. According to the Chou-Fasman model, the enzyme has 41.4% of alpha-helics, 16.2%, beta-strands, 14.4%, beta-turns. 14 of the 35 Pro were located at the second sites of beta-turns. Hydrophobic interaction, ion bond, alpha-helics and Pro had important contribution to Tn-gly thermostability.
Amino Acid Sequence ; Cloning, Molecular ; Escherichia coli ; genetics ; Glycoside Hydrolases ; biosynthesis ; classification ; genetics ; Hot Temperature ; Molecular Sequence Data ; Open Reading Frames ; genetics ; Phylogeny ; Protein Structure, Secondary ; physiology ; Recombinant Proteins ; biosynthesis ; genetics ; Sequence Analysis, DNA ; methods ; Sequence Homology ; Thermus ; enzymology ; beta-Glucosidase