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BACKGROUND Smilax china root, which is rich in resveratrol and oxyresveratrol, has been used as emergency foods as well as folk medicine. This study investigated changes in concentration of bioactive components and the free-radical scavenging capacity of Smilax china root during fermentation by Aspergillus usami and Saccharomyces cerevisiae. RESULTS Resveratrol, oxyresveratrol and piceid were quantified as major constituents in Smilax china root by using UPLC-ESI-MS. The concentration of oxyresveratrol and resveratrol remarkably increased through fermentation and the transformation of piceid to resveratrol. Its concentration in 4% Smilax china root was 1.16-2.95 times higher than that of a 2% preparation throughout fermentation. The vitamin C equivalent antioxidant capacity of 2% Smilax china root was 1.51-1.91 times higher than that of 4% Smilax china root during fermentation. Meanwhile, ABTS free-radical scavenging capacity was enhanced up to 95.07 and 99.35% for 2% and 4% Smilax china root, respectively. CONCLUSION Results from our study propose that bioactive components in Smilax China root were highly extracted by fermentation followed by saccharification and ethanol production, resulting in enhanced free-radical scavenging capacity. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Bacteriophytochromes (BphP) are phytochrome-like light sensing proteins in bacteria, which use biliverdin as a chromophore. In order to study the biochemical properties of the DrBphP protein, five (2B8, 2C11, 3B2, 3D2, and 3H7) anti-DrBphP monoclonal antibodies were produced through the immunization of mice with purified full-length DrBphP and DrBphN (1-321 amino acid) proteins, and epitope mapping was then carried out. Among the five antibodies, 2B8 and 2C11 preferentially recognized the N-terminal region of BphP whereas 3B2, 3D2, and 3H7 showed preference for the C-terminal region. We performed further epitope mapping using recombinant truncated BphP proteins to narrow down their target sequences. The results demonstrated that each of the five monoclonal antibodies recognized different regions on the DrBphP protein. Additionally, epitopes of 2B8 and 3H7 antibodies were discovered to be shorter than 10 amino acids (2B8: RDPLPFFPP, 3H7: PGEIEEA). These two antibodies with such specific recognition epitopes could be especially valuable for developing new peptide tags for protein detection and purification. [ABSTRACT FROM AUTHOR]

The pharmacokinetic interaction of enrofloxacin and trimethoprim was evaluated after single-dose intraperitoneal or oral co-administration in rats. Plasma concentrations of the two drugs were determined by high-performance liquid chromatography. Following intraperitoneal combination, a significant ( P < 0.05) increase in mean values of plasma half-life ( t) and maximum plasma concentration ( C) was observed for enrofloxacin and trimethoprim, respectively. There was a significant ( P < 0.05) increase in mean values of area under the plasma drug concentration versus time from time zero to infinity (AUC) and C between combined oral doses (10, 30 and 100 mg/kg) of both antibacterial drugs. Also, after oral conjugation a significant difference in mean values of MRT was observed between lower (10 mg/kg) and higher (100 mg/kg) doses of both drugs. A significant increase in pharmacokinetic parameters of both drugs in combined intraperitoneal and oral doses indicated pharmacokinetic interaction of enrofloxacin and trimethoprim. Further study is recommended in other species of animals. [ABSTRACT FROM AUTHOR]

The production of cellulase using solid-state fermentation of rice straw by the mutant strain Hypocrea koningii RSC1 was studied. Optimization of culture conditions, such as the nitrogen source, pH, and temperature, resulted in a maximum filter paper cellulase activity of 44.15 U g−1 substrate, a carboxymethylcellulase activity of 324.6 U g−1 substrate, and a β-glucosidase activity of 7.45 U g−1 substrate. Saccharification of untreated, 1% H2SO4-treated, and 2.5% NaOH-treated rice straw using the RSC1 cellulase resulted in 19, 17, and 34 g L−1 of reducing sugar, respectively. Further studies on the morphological and compositional changes of rice straw upon treatment with the cellulase by scanning electron microscopy analysis and Fourier transform infrared spectroscopy revealed the disruption of the arrangement of fibers and changes in the functional groups that occur in cellulose. X-ray diffraction analysis revealed a reduction in crystallinity of the rice straw upon treatment with the cellulase. Our study shows that H. koningii RSC1 could be a good choice for the production of cellulase and reducing sugars from rice straw. [ABSTRACT FROM AUTHOR]

Biological control and plant growth promotion by plant beneficial microbes has been viewed as an alternative to the use of chemical pesticides and fertilizers. Bacteria and fungi that are naturally associated with plants and have a beneficial effect on plant growth by the alleviation of biotic and abiotic stresses were isolated and developed into biocontrol (BCA) and plant growth-promoting agents (PGPA). Actinobacteria are a group of important plant-associated spore-forming bacteria, which have been studied for their biocontrol, plant growth promotion, and interaction with plants. This review summarizes the effects of actinobacteria as BCA, PGPA, and its beneficial associations with plants. [ABSTRACT FROM AUTHOR]

Due to the increasing emergence of drug-resistant bacteria and tumor cell lines, novel antibiotics with antibacterial and cytotoxic activities are urgently needed. Marine actinobacteria are rich sources of novel antibiotics, and here we report the discovery of a novel alkaloid, xinghaiamine A, from a marine-derived actinomycete Streptomyces xinghaiensis NRRL B24674T. Xinghaiamine A was purified from the fermentation broth, and its structure was elucidated based on extensive spectroscopic analysis, including 1D and 2D NMR spectrum as well as mass spectrometry. Xinghaiamine A was identified to be a novel alkaloid with highly symmetric structure on the basis of sulfoxide functional group, and sulfoxide containing compound has so far never been reported in microorganisms. Biological assays revealed that xinghaiamine A exhibited broad-spectrum antibacterial activities to both Gram-negative persistent hospital pathogens (e.g. Acinetobacter baumannii, Pseudomonas aeruginosa and Escherichia coli) and Gram-positive ones, which include Staphylococcus aureus and Bacillus subtilis. In addition, xinghaiamine A also exhibited potent cytotoxic activity to human cancer cell lines of MCF-7 and U-937 with the IC50 of 0.6 and 0.5 µM, respectively. [ABSTRACT FROM AUTHOR]

FK506 production by a mutant strain ( Streptomyces sp. RM7011) induced by N-methyl- N′-nitro- N-nitrosoguanidine and ultraviolet mutagenesis was improved by 11.63-fold (94.24 mg/l) compared to that of the wild-type strain. Among three different metabolic pathways involved in the biosynthesis of methylmalonyl-CoA, only expression of propionyl-CoA carboxylase (PCC) pathway led to a 1.75-fold and 2.5-fold increase in FK506 production and the methylmalonyl-CoA pool, respectively, compared to those of the RM7011 strain. Lipase activity of the high FK506 producer mutant increased in direct proportion to the increase in FK506 yield, from low detection level up to 43.1 U/ml (12.6-fold). The level of specific FK506 production and lipase activity was improved by enhancing the supply of lipase inducers. This improvement was approximately 1.88-fold (71.5 mg/g) with the supplementation of 5 mM Tween 80, which is the probable effective stimulator in lipase production, to the R2YE medium. When 5 mM vinyl propionate was added as a precursor for PCC pathway to R2YE medium, the specific production of FK506 increased approximately 1.9-fold (71.61 mg/g) compared to that under the non-supplemented condition. Moreover, in the presence of 5 mM Tween 80, the specific FK506 production was approximately 2.2-fold (157.44 mg/g) higher than that when only vinyl propionate was added to the R2YE medium. In particular, PCC expression in Streptomyces sp. RM7011 (RM7011/pSJ1003) together with vinyl propionate feeding resulted in an increase in the FK506 titer to as much as 1.6-fold (251.9 mg/g) compared with that in RM7011/pSE34 in R2YE medium with 5 mM Tween 80 supplementation, indicating that the vinyl propionate is more catabolized to propionate by stimulated lipase activity on Tween 80, that propionyl-CoA yielded from propionate generates methylmalonyl-CoA, and that the PCC pathway plays a key role in increasing the methylmalonyl-CoA pool for FK506 biosynthesis in RM7011 strain. Overall, these results show that a combined approach involving classical random mutation and metabolic engineering can be applied to supply the limiting factor for FK506 biosynthesis, and vinyl propionate could be successfully used as a precursor of important methylmalonyl-CoA building blocks. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the reaction of extracellular Adenosine triphosphatase (extATP) concentration to hypertonic stress and its functions in stress protection. It made used of seeds of Arabidopsis thaliana and methods such as hypertonic stress treatments and quantitative analysis of exATP concentration. It was found out that changes in its concentration are transient and seeds reduce its concentration. ExATP was found out as protection from hydrogen peroxide stress.

In this study, three trehalose gene clusters, treX- Y- Z, tpS1, and treS, of the acarbose-producing strain, Actinoplanes sp. SN223/29, have been identified. In particular, five trehalose synthetic genes were sequenced and characterized in detail. They were cloned and expressed in Escherichia coli BL21(DE3)pLysS using the His-tag vector pET19b. The recombinant proteins were purified by Ni2+-nitrilotriacetic acid agarose affinity chromatography, and their functions were characterized biochemically. Both the maltooligosyltrehalose synthase (TreY–TreZ) pathway and the trehalose synthase (TreS) pathway have maximum activity at 40°C and at pH 7.5 and 7.0, respectively, in 100-mM phosphate buffer. Meanwhile, the trehalose-6-phosphate synthase (TpS1) showed maximum activity at 35°C and at pH 7.5 in 100 mM Tris–HCl. As a cofactor candidate, Mg2+ enhanced the activities of all three trehalose synthetic reactions significantly. TreY produced component C from acarbose by its proposed isomerase activity, but TreS did not. This study suggests that the mutation of treY can improve acarbose production by repressing component C production. Based on the data obtained in this study, a model for component C production in Actinoplanes sp. SN 223/29 is proposed. [ABSTRACT FROM AUTHOR]

Because ATP is an extracellular effector in animal and plant systems and derivatives of ATP, such as S-adenosylmethionine and cAMP, can control antibiotic production and morphological differentiation in Streptomyces, we hypothesized that extracellular ATP (exATP) can also affect physiologies of Streptomyces. We found that the addition of 10 μM exATP to Streptomyces coelicolor A3(2) cultures resulted in enhanced actinorhodin and undecylprodigiosin production and morphological differentiation on solid medium. However, these phenotypes were reduced by the addition of a 10-fold higher concentration of exATP (100 μM). Intracellular ATP concentrations were also modulated in response to changes in exATP. ATP analogs, added at a 100-fold lower concentration, affected Streptomyces similarly to that seen for 10 μM exATP. The enhanced promoter activity of actII-orf4 indicated that 10 μM exATP affect the transcriptional level for actinorhodin production. Results from this study suggest that exATP is an effector for the physiology of S. coelicolor and careful manipulation of exATP may significantly enhance the high-yield production of antibiotics by S. coelicolor. [ABSTRACT FROM AUTHOR]

Abstract: S-Adenosylmethionine (SAM), the major methyl donor in diverse biological processes, was recently found to be involved in the regulation of differentiation in streptomycetes. Exogenous SAM, in a quantity as low as 2μM, enhanced antibiotic production and inhibited morphological development of Streptomyces coelicolor M145. Total protein profiling of S. coelicolor M145 revealed that SAM enhanced the expression of oligopeptide-binding components related to ABC transporters that included BldK, a well-known regulatory factor in S. coelicolor differentiation. A radiolabeled SAM feeding experiment verified that exogenous SAM can be imported into the cell, which is under the control of the bld cascade. This study substantiated that BldK serves as a transducer of the SAM signal and uncovered the possible role of oligopeptide import in the regulation of Streptomyces differentiation, particularly in relation to SAM. [Copyright &y& Elsevier]

The effect of S-adenosylmethionine (SAM) on the production of various antibiotics was investigated to determine whether SAM-dependent methylation is required in biosynthetic pathways of antibiotics. Pristinamycin IIB and granaticin do not require SAM-dependent methylation in their biosynthesis pathways, and production of these two antibiotics was increased about 2-fold when a low concentration (50 and 10 μM, respectively) of SAM was treated; in contrast, oleandomycin and avermectin B1a require SAM as a methyl donor in their biosynthesis, and production of these two antibiotics was increased 5-fold and 6-fold, depending on the SAM concentration within a certain range. We also found that the transcription of a pathway-specific regulator, gra-ORF9, was activated by exogenous SAM treatment. Production of oleandomycin and avermectin B1a was decreased by using a methyltransferase inhibitor, sinefungin, but the production levels of these antibiotics were restored to the control level by simultaneously adding SAM and sinefungin. Interestingly, we have found a similar stimulatory effect of S-adenosylhomocysteine (SAH), the methylation product of SAM, on antibiotic production in the four strains. Our results clearly demonstrate the widespread activation of antibiotic production using SAM in streptomycetes. [Copyright &y& Elsevier]

The catabolism of branched chain amino acids, especially valine, appears to play an important role in furnishing building blocks for macrolide and polyether antibiotic biosyntheses. To determine the active site residues of ValDH, we previously cloned, partially characterized, and identified the active site (lysine) of Streptomyces albus ValDH. Here we report further characterization of S. albus ValDH. The molecular weight of S. albus ValDH was determined to be 38 kDa by SDS-PAGE and 67 kDa by gel filtration chromatography indicating that the enzyme is composed of two identical subunits. Optimal pHs were 10.5 and 8.0 for dehydrogenase activity with valine and for reductive amination activity with α-ketoisovaleric acid, respectively. Several chemical reagents, which modify amino-acid side chains, inhibited the enzyme activity. To examine the role played by the residue for enzyme specificity, we constructed mutant ValDH by substituting alanine for glycine at position 124 by site-directed mutagenesis. This residue was chosen because it has been considered to be important for substrate discrimination by phenylalanine dehydrogenase (PheDH) and leucine dehydrogenase (LeuDH). The Ala-124–Gly mutant enzyme displayed lower activities toward aliphatic amino acids, but higher activities toward L-phenylalanine, L-tyrosine, and L-methionine compared to the wild type enzyme suggesting that Ala-124 is involved in substrate binding in S. albus ValDH. [ABSTRACT FROM AUTHOR]

The genetic region (sitISR) located in a putative integrating element of Streptomyces albus ATCC 21838 was able to enhance biosyntheses of actinorhodin and undecylprodigiosin when introduced into Streptomyes lividans TK-24. The heterologous expression in S. lividans TK-24 indicated that sitS and sitR activated the antibiotic productions and sitI repressed the productions. The sitI-expression also repressed morphological development on regeneration agar. Promoter activity assay showed that the sitS-transcription was repressed by SitR. When sitI and sitR were co-expressed, the SitR-mediated activation of antibiotic production was repressed but derepressed after the growth ceased, resulting in growth-dissociated overproduction of undecylprodigiosin. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases, such as stroke, are the most common causes of death in developed countries. Ischemic stroke accounts for 85% of the total cases and is caused by abnormal thrombus formation in the vessels, causing deficient blood and oxygen supply to the brain. Prophylactic treatments include the prevention of thrombus formation, of which the most used is acetylsalicylic acid (ASA); however, it is associated with a high incidence of side effects. Angelica gigas Nakai (AG) is a natural herb used to improve blood circulation via anti-platelet aggregation, one of the key processes involved in thrombus formation. We examined the antithrombotic effects of AGE 232, the ethanol extract of A. gigas Nakai. AGE 232 showed a significant reduction in death or paralysis in mice caused by collagen/epinephrine-induced thromboembolism in a dose-dependent manner and inhibition of collagen-induced human platelet aggregation in a concentration-dependent manner. Additionally, AGE 232-treated mice did not show severe bleeding in the gut compared to ASA-treated mice. AGE 232 resulted in a decrease in the number of neutrophils attached to the human umbilical vein endothelial cells (HUVECs) and lower inhibition of COX-1 in response to bleeding and damage to blood vessels, a major side effect of ASA. Therefore, AGE 232 can prevent thrombus formation and stroke. [ABSTRACT FROM AUTHOR]

Chemotherapy-induced neuropathic pain (CINP) is a severe adverse effect of platinum- and taxane-derived anticancer drugs. The pathophysiology of CINP includes damage to neuronal networks and dysregulation of signal transduction due to abnormal Ca2+ levels. Therefore, methods that aid the recovery of neuronal networks could represent a potential treatment for CINP. We developed a mouse model of paclitaxel-induced peripheral neuropathy, representing CINP, to examine whether intrathecal injection of decursin could be effective in treating CINP. We found that decursin reduced capsaicin-induced intracellular Ca2+ levels in F11 cells and stimulated neurite outgrowth in a concentration-dependent manner. Decursin directly reduced mechanical allodynia, and this improvement was even greater with a higher frequency of injections. Subsequently, we investigated whether decursin interacts with the transient receptor potential vanilloid 1 (TRPV1). The web server SwissTargetPrediction predicted that TRPV1 is one of the target proteins that may enable the effective treatment of CINP. Furthermore, we discovered that decursin acts as a TRPV1 antagonist. Therefore, we demonstrated that decursin may be an important compound for the treatment of paclitaxel-induced neuropathic pain that functions via TRPV1 inhibition and recovery of damaged neuronal networks. [ABSTRACT FROM AUTHOR]

The efficient culture and purification of antimicrobial peptides (AMPs), along with intense antioxidant activity, have drawn the interest to study antioxidant activity mechanism. We report the culture conditions optimization, efficient biosynthesis, and purification of an antioxidant peptide MS15 from Bacillus velezensis obtained from fermented food that would generate heme oxygenase-1 (HO-1) expression and lead to nuclear factor erythroid 2-related factor-2 (Nrf2) nuclear translocation. We explored the ability of kinetics and potency for the bacterial killing to work against various pathogenic bacteria. A bioassay showed the lysis zone of MS15 by tricine SDS-PAGE near at 6 kDa. MALDI-TOF/MS verified molecular weight, and the existence of a molecular mass of 6091 Da was reported by purity. The MIC of MS15 ranged from 2.5–160 μg/mL for many pathogenic bacteria, showing greater potency. In macrophage RAW 264.7 cells, MS15 was exposed to assess its inhibitory effect against the generation of reactive oxygen species (ROS) in oxidative stress. In the sample treated group, the translation, and transcriptional levels of CAT (catalase), GPx (glutathione peroxidase), and SOD (superoxide dismutase) were significantly greater. In short, MS15 has significant antioxidant properties, reducing ROS production in RAW 264.7 cells, and raising the translation and transcriptional rates of antioxidant enzymes with stimulating HO-1 induction facilitated by Nrf2. [ABSTRACT FROM AUTHOR]