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The morphology of Spirulina during cultivation is susceptible to external interferences, but the morphogenesis mechanism is still unclear. Here the proteomic changes of linear Spirulina and spiral Spirulina were comparatively investigated via isobaric tag for relative and absolute quantitation (iTRAQ). Totally 165 and 167 differences in proteins expression were screened out from the TJSD2/TJSD3 and TJBC4-1/TJBC4-2 groups, respectively. Gene ontology and metabolic pathway analysis of differences in proteins expression uncovered the metabolic pathways (photosynthesis, carbon fixation, sugar metabolism) that were significantly enriched with the proteins correlated with Spirulina morphogenesis. The results of differences in proteins expression in metabolic pathway were verified by quantitative real-time PCR. We also built a putative model of Spirulina morphogenesis mechanism and thought multiple metabolic pathways interact and take part in Spirulina morphogenesis.

High PMIn Guangzhou, from March 5Among the Guangzhou samples,In conclusion, the diversity and specificity of microbial components in Guangzhou PM

Marine Streptomyces sp. CC0208 isolated from the Bohai Bay showed high efficiency of cellulose degradation under optimized fermentation parameters. Also, as one of the bioinformatics-based approaches for the discovery of novel natural product and enzyme effectively, genome mining has been developed and applied widely. Herein, we reported the complete genome sequence of Streptomyces sp. CC0208.Whole-genome sequencing analysis revealed a genome size of 9,325,981 bp with a linear chromosome, GC content of 70.59% and 8487 protein-coding genes. Abundant genes have predicted functions in antibiotic metabolism and enzymes. A 20 enzymes closely associated with cellulose degradation were discovered. A total of 25 biosynthetic gene clusters (BGCs) of secondary metabolites were identified, including diverse classes of natural products. The availability of genome sequence of Streptomyces sp. CC0208 not only will assist in cracking the mechanism of cellulose degradation but also will provide the insights into the significant secondary metabolic potentials for the production of diverse compound classes based on rational strategies.

Two kinds of Yb3+ doped silicate laser glass with little difference were produced by high temperature of melting process. The absorption and emission spectra of the two glass samples were tested by the correlative spectrographs; the integral absorption cross section, stimulated emission cross section, fluorescence line-width, fluorescence lifetime, least particle count, saturation pump intensity and least pump intensity of the Yb3+ -doped laser glasses were calculated respectively, and by comparison it was found that the chart of the absorption cross section is similar to the stimulated emission cross section calculated by the reciprocity method, and is very different from the stimulated emission cross section calculated by the Fuchbauer-Ladenburger method. This result is precisely in line with the theoretical analysis. The line-types of the absorption spectra of the two glass samples are almost the same, and the first peak value of absorption is located at 975 nm while the second peak value is at 908 nm. As the two components of the samples are not very different, the accord of the line-types of the absorption spectra indicates that the makeup of the glass material is the primary factor influencing the line-type of the absorption spectra. The fluorescence spectra of the two glass samples are very different, and the first fluorescence peak value of sample one is located at 993 nm with the second peak value at 1029 nm, while the first fluorescence peak value of sample two is located at 1 035 nm with the second peak value at 994 nm. The cause of the major difference in the fluorescence spectra of two samples lies in the different doping density of Yb3+. By comparison we found that the laser performance of sample two is better than that of sample one. The test shows that both samples are suitable for drawing fiber.

The cadmium silicate glass samples of 40SiO 2 -14Al 2 O 3 -(40-x) CdO-2Li 2 O-2K 2 O-2Na 2 O-xEr 2 O 3 (x=0.15, 0.20, 0.25, 0.30, 0.35, 0.40 mol) was prepared by high-temperature solid-state reaction method, and it is pumped at 488 nm, 532 nm and 800 nm respectively. The results indicate that the main peak wavelengths are at 547 nm, 731 nm and 1534 nm excited at 488 nm. The relationship of the intensity between the emission light of 731 nm and Er3 + -doped concentration is nonlinear. Near-infrared light nearby 1534 nm is excited at 532 nm and 800 nm, but it is weaker at 800 nm. The glass samples open a outlook of application for conversion luminescence materials.

The glass samples of SiO 2 -Al 2 O 3 -CdO-Li 2 O-K 2 O-Na 2 O with different Nd 3+ -doped concentration are prepared by high-temperature solid-state reaction method, and test the absorption spectrums as well as emission spectrum excited at 488 nm, 532 nm and 808 nm. The third-order optical nonlinear properties of glasses samples are investigated by the z-scan technique. With the increment of doping concentration of Nd 3+ , the third-order nonlinear refractive index and the absorption index increase, so it belongs to the self-focusing and reverse saturated absorption medium. The glass samples open a outlook of application for nonlinear optical medium and excellent luminescence materials.