Background: Streptomyces lincolnensis is well known for producing the clinically important antimicrobial agent lincomycin. The synthetic and regulatory mechanisms on lincomycin biosynthesis have been deeply explored in recent years. However, the regulation involved in primary metabolism have not been fully addressed.
View Article and Find Full Text PDFA generalized nonlinear Schrödinger equation is studied with the interplay between Kerr nonlinearity and intensity-dependent dispersion. The supported soliton solutions are characterized analytically in different families by the pseudo-potential method, in terms of Maimistov and Cuspon solitons for different ratio between the intensity-dependent dispersion and Kerr nonlinearity. Direct numerical simulations also agree with our analytical formulas.
View Article and Find Full Text PDFAntibiotic fermentation residue flocculated by polymeric ferric sulfate (PFS) has been classified as a "hazardous waste" in China. In this study, it was recycled into antibiotic fermentation residue biochar (AFRB) by pyrolysis and used as a heterogeneous electro-Fenton (EF) catalyst for ciprofloxacin (CIP) degradation. The results show that PFS was reduced to Fe and FeS during pyrolysis, which was beneficial for the EF process.
View Article and Find Full Text PDFAn efficient and thorough water disinfection is critical for human health. In this study, UVA-LEDs, nitrilotriacetic acid (NTA) and a boron-doped diamond anode were respectively used as the UVA source, the iron chelator and the anode for the UVA/electro-Fenton (E-Fenton) reaction to treat wastewater. The disinfection performance of the UVA/E-Fenton had been investigated.
View Article and Find Full Text PDFMitochondrial DNA B Resour
February 2020
We reported the first mitogenome of from (Orobanchaceae), which is endemic to SW China. The complete mitochondrial genome (mitogenome or chondriome) was a single circular chromosome that was 219,859 bp in length. It contains 56 genes, including 34 protein-coding ( and with two copies), 19 transfer RNA (tRNA), and three ribosomal RNA (rRNA) genes.
View Article and Find Full Text PDFSoliton solutions are studied for paraxial wave propagation with intensity-dependent dispersion. Although the corresponding Lagrangian density has a singularity, analytical solutions, derived by the pseudo-potential method and the corresponding phase diagram, exhibit one- and two-humped solitons with almost perfect agreement to numerical solutions. The results obtained in this work reveal a hitherto unexplored area of soliton physics associated with nonlinear corrections to wave dispersion.
View Article and Find Full Text PDFMonensin, produced by Streptomyces cinnamonensis, is a polyether ionophore antibiotic widely used as a coccidiostat and a growth-promoting agent in agricultural industry. In this study, cyclic AMP receptor protein (Crp), the global transcription factor for regulation of monensin biosynthesis, was deciphered. The overexpression and antisense RNA silencing of crp revealed that Crp plays a positive role in monensin biosynthesis.
View Article and Find Full Text PDFBackground: Lincomycin, produced by Streptomyces lincolnensis, is a lincosamide antibiotic and widely used for the treatment of the infective diseases caused by Gram-positive bacteria. The mechanisms of lincomycin biosynthesis have been deeply explored in recent years. However, the regulatory effects of LmbU that is a transcriptional regulator in lincomycin biosynthetic (lmb) gene cluster have not been fully addressed.
View Article and Find Full Text PDFZhongguo Shi Yan Xue Ye Xue Za Zhi
December 2018
To explore resonance phenomena in the nonlinear region, we show by experimental measurements and theoretical analyses that resonance happens in modulation instability from non-instantaneous nonlinearities in photorefractive crystals. With a temporally periodic modulation in the external bias voltage, corresponding to a modulation in the nonlinear strength, an enhancement in the visibility of MI at resonant frequency is reported through spontaneous optical pattern formations. Theoretical curves obtained from a nonlinear non-instantaneous Schrödinger equation give good agreement to experimental data.
View Article and Find Full Text PDFJ Ind Microbiol Biotechnol
December 2016
The polyether ionophore antibiotic monensin is produced by Streptomyces cinnamonensis and is used as a coccidiostat for chickens and growth-promoting agent for cattle. Monensin biosynthetic gene cluster has been cloned and partially characterized. The GntR-family transcription factor DasR regulates antibiotic production and morphological development in Streptomyces coelicolor and Saccharopolyspora erythraea.
View Article and Find Full Text PDFFisetin is an effective compound extracted from lacquer which has been used in the treatment of various diseases. Preliminary data indicate that it also exerts specific anti-cancer effects. However, the manner in which fisetin regulates cancer growth remains unknown.
View Article and Find Full Text PDFWe report experimental observation of lasing on surface states, in the form of standing waves at the termination of a defect-free photonic crystal on top of vertical-cavity surface-emission lasers. Direct images of lasing modes at the truncated periodic potential, along one side of a square lattice, are demonstrated by collecting near-field radiation patterns, as well as in numerical simulations. Our results provide a step toward realizing surface and edge states in optical cavities.
View Article and Find Full Text PDFObjective: To explore the safety and efficacy of a therapeutic regimen for treating severe aplastic anemia (SAA) in its early stage.
Methods: Two groups of SAA patients were enrolled in the present study. One was a treatment group including 21 patients being treated with anti-CD(4), CD(8) monoclonal antibodies as well as cyclosporine A.