Activity

In addition, an intrinsic ChrB protein fluorescence assay suggested that pH and salinity may influence the Cr(VI) adsorption capacity of ChrB-expressing E. coli cells by modulating the ChrB protein conformation. Although the characteristics of ChrB may not be universal for all metal-binding proteins, our study provides new insights into different engineering strategies for whole-cell biosorbents for removing heavy metals from industrial effluents.This study aimed to determine the immune-stimulating effects of heat-killed Lactobacillus plantarum Ln1 (HK-Ln1) through the production of nitric oxide (NO) and pro-inflammatory cytokine achieved by inducing NF-κB and mitogen-activated protein kinase (MAPK)-signaling pathways in macrophages. learn more HK-Ln1 showed higher NO and cytokine production compared to control (non-stimulated lipopolysaccharide); in addition, the expression of inducible nitric oxide synthase (iNOS) was induced through HK-Ln1treatment. The phosphorylation of IκB-α and p65 increased following treatment by HK-Ln1, which implicates IκB-α degradation and the translocation of p65 to nucleus. In addition, the phosphorylation of MAPKs, ERK 1/2, JNK, and p38 was induced following HK-Ln1 treatment.Land subsidence induced by underground coal mining leads to severe ecological and environmental problems. Arbuscular mycorrhizal (AM) fungi have the potential to improve plant growth and soil properties. We aimed to assess the effects of AM fungi on the growth and soil properties of sea buckthorn under field conditions at different reclamation times. Inoculation with arbuscular mycorrhizal fungi significantly promoted the survival rate over a 50-month time period. Inoculation significantly increased plant height after 14, 26, and 50 months. Crown width after 14 months and ground diameter after 50 months of inoculation treatment were significantly higher than in the uninoculated treatment. AMF inoculation significantly increased plant mycorrhizal colonization rate and promoted an increase in mycelial density in the rhizosphere soil. The pH and electrical conductivity of rhizosphere soil increased after inoculation. After 26 and 50 months the soil organic matter in the inoculation treatment was significantly higher than in the control. The number of inoculated soil rhizosphere microorganisms increased and acid phosphatase activity increased. AMF inoculation may play an active role in promoting plant growth and improving soil quality in the long term and is conducive to the rapid ecological restoration of damaged mining areas.Bicarbonate has been considered as a better approach to supply CO2 to microalgae cells’ microenvironment than gas bubbling owing to cost-effectiveness and easy operation. However, the β-carotene production was too low in D. salina cultivated with bicarbonate in previous studies. Also, the difference on photosynthetic efficiency between these two carbon sources (bicarbonate and CO2) was seldom discussed. In this study, the culture conditions, including NaHCO3, Ca2+, Mg2+ and microelements’ concentrations, were optimized when bicarbonate was used as carbon source. Under optimized condition, the maximum biomass concentration of 0.71 g·L-1 and corresponding β-carotene content of 4.76% was obtained, with β-carotene yield of 32.0 mg·L-1, much higher than previous studies with NaHCO3. Finally, this optimized conditions with bicarbonate were compared with CO2 bubbling by online monitoring. There is notable difference in Fv/Fm value between cultivations with bicarbonate and CO2, but there was no difference in the Fv/Fm periodic changing patterns. This indicates that high concentration of NaHCO3 used in this study played as a stress factor for β-carotene accumulation, although high productivity of biomass still obtained.Monoclonal antibodies are widely used as diagnostic reagents and for therapeutic purposes, and their demand is increasing extensively. To produce these proteins in sufficient quantities for commercial use, it is necessary to raise the output by scaling up the production processes. This review describes recent trends in high-density cell culture systems established for monoclonal antibody production that are excellent methods to scale up from the lab-scale cell culture. Among the reactors, hollow fiber bioreactors contribute to a major part of high-density cell culture as they can provide a tremendous amount of surface area in a small volume for cell growth. As an alternative to hollow fiber reactors, a novel disposable bioreactor has been developed, which consists of a polymer-based supermacroporous material, cryogel, as a matrix for cell growth. Packed bed systems and disposable wave bioreactors have also been introduced for high cell density culture. These developments in high-density cell culture systems have led to the monoclonal antibody production in an economically favourable manner and made monoclonal antibodies one of the dominant therapeutic and diagnostic proteins in biopharmaceutical industry.Platycodon grandiflorum root (Platycodi radix) saponins, platycosides, have been used as health supplements and food items for the treatment of respiratory disorders and pulmonary diseases. Deglycosylated saponins have been known to exert stronger biological effects than their glycosylated forms. In the present study, glycosylated platycosides in Platycodi radix extract were biotransformed into deglycosylated 3-O-β-D-glucopyranosyl platycosides, including 3-O-β-D-glucopyranosyl platycodigenin, 3-O-β-D-glucopyranosyl polygalacic acid, and 3-O-β-D-glucopyranosyl platyconic acid, by pectinase from Aspergillus aculeatus. This is the first report on the quantitative enzymatic production of 3-O-β-D-glucopyranosyl platycosides. The chemical structures of 3-O-β-D-glucopyranosyl platycosides were identified with LC/MS. The biotransformation pathways of three-type platycosides in Platycodi radix into 3-O-β-D-glucopyranosyl platycosides were established.Mycobacterium tuberculosis produce mycolic acids which are relevant for persistence, recalcitrance to antibiotics and defiance to host immunity. c-di-GMP is a second messenger involved in transition from planktonic cells to biofilms, whose levels are controlled by diguanylate cyclases (DGC) and phosphodiesterases (PDE). The transcriptional regulator dosR, is involved in response to low oxygen, a condition likely happening to a subset of cells within biofilms. Here, we found that in M. bovis BCG, expression of both BCG1416c and BCG1419c genes, which codes for a DGC and a PDE, respectively, decreased in both stationary phase and during biofilm production. The kasA, kasB, and fas genes, which are involved in mycolic acid biosynthesis, were induced in biofilm cultures, as it was dosR, therefore suggesting an inverse correlation in their expression compared with that of genes involved in c-di-GMP metabolism. The relative abundance within trehalose dimycolate (TDM) of α-mycolates decreased during biofilm maturation, with methoxy mycolates increasing over time, and keto species remaining practically stable.