Azalomycin F4a 2-ethylpentyl ester,a new 36-membered macrocyclic lactone antibiotic,was isolated from mangrove actinomycete Streptomyces sp.211726.Its structure was elucidated on the basis of spectroscopic data.The co...Azalomycin F4a 2-ethylpentyl ester,a new 36-membered macrocyclic lactone antibiotic,was isolated from mangrove actinomycete Streptomyces sp.211726.Its structure was elucidated on the basis of spectroscopic data.The compound showed broad-spectrum antifungal activity and moderate cytotoxicity against human colon tumor cell HCT-116.展开更多
Inoculation density has a marked effect on nodulation and N fixation in soybean (Glycine max L.). Therefore, we conducted this study to determine the optimal inoculation density of Bradyhizobium japonicum SAY3-7 (SAY3...Inoculation density has a marked effect on nodulation and N fixation in soybean (Glycine max L.). Therefore, we conducted this study to determine the optimal inoculation density of Bradyhizobium japonicum SAY3-7 (SAY3-7) and Streptomyces griseoflavus P4 (P4) for plant growth, nodulation, and N fixation, and to investigate the effect of co-inoculation on selected soybean cultivars, using the optimal inoculation density. Nitrogen fixation, in terms of an acetylene reduction activity value, was measured using a flame ionization gas chromatograph. In this study, low-density single inoculation with P4 (10<sup>5</sup> or 10<sup>6</sup> cells mL<sup>-1</sup>) was associated with the highest plant biomass, compared with normal- and high-density single inoculation with P4 (10<sup>7</sup> or 10<sup>8</sup> cells mL<sup>-1</sup>). Moreover, low-density single or co-inoculations with SAY3-7 and/or P4 produced the highest nodule biomass and highest nitrogenase activity, compared with single or dual inoculation at other inoculation densities. Therefore, we evaluated low-density co-inoculation with P4 and SAY3-7, at the rate of 10<sup>5</sup> cells mL<sup>-1</sup>, on selected soybean cultivars. Low-density co-inoculation increased the plant biomass, compared with un-inoculated plants. The effects of single and co-inoculation on nodulation did not differ significantly for any of the cultivars, except “Yezin-9” in the first experiment and “Shan Seine” in the second experiment. Low-density inoculation with both bacteria increased N fixation by 15% - 75% for seven of the cultivars in the first experiment and by 15% - 39% for three of the cultivars in the second experiment, compared with single inoculation with SAY3-7. Based on the overall results, we concluded that low-density co-inoculation with P4 and SAY3-7 gave improved plant growth and N fixation.展开更多
(4S,5R)-5-Hydroxy-4-decanolide ,the proposed autoregulator from streptomyces Griseus was synthesized from an allyl alcohol 2,employ- ing the Sharpless kinetic resolution and the reaction of diethyl malonate with the ...(4S,5R)-5-Hydroxy-4-decanolide ,the proposed autoregulator from streptomyces Griseus was synthesized from an allyl alcohol 2,employ- ing the Sharpless kinetic resolution and the reaction of diethyl malonate with the epoxy compound as two key steps.展开更多
A new degraded sesquiterpene was isolated from the marine actinomycete Streptomyces sp. 0616208. Its structure was elucidated as （1α; 4aα; 5α, 7β, 8aβ）-5, 8a-dimethyl-decahydrona- phthalene-1, 4a, 7-triol on th...A new degraded sesquiterpene was isolated from the marine actinomycete Streptomyces sp. 0616208. Its structure was elucidated as （1α; 4aα; 5α, 7β, 8aβ）-5, 8a-dimethyl-decahydrona- phthalene-1, 4a, 7-triol on the basis of spectroscopic data.展开更多
Four groups of antibiotic activity compounds were separated and purified from the ethyl acetate fraction of a broth culture of Streptomyces herbaricolor HNS2-2.Trace analyses were performed and anti-microbial activiti...Four groups of antibiotic activity compounds were separated and purified from the ethyl acetate fraction of a broth culture of Streptomyces herbaricolor HNS2-2.Trace analyses were performed and anti-microbial activities were determined. The antibiotic activity compounds were identified as quercetin dehydrate ①, p-hydroxyphenyl ②, 4’-hydroxyflavanone ③, and 3-hydroxyflavone ④ based on spectroscopic data. Compounds 1-4 showed significant antimicrobial activities against Staphylococcus aureus and the tobacco mosaic virus in vitro, suggesting their potential agricultural and medical applications.展开更多
otrA resembles elongation factor G （EF-G） and is considered to be an oxytetracycline （OTC）-resistance determinant in Streptomyces rimosus. In order to determine whether otrA also conferred resistance to OTC and ot...otrA resembles elongation factor G （EF-G） and is considered to be an oxytetracycline （OTC）-resistance determinant in Streptomyces rimosus. In order to determine whether otrA also conferred resistance to OTC and other aminoglycosides to Streptomyces coelicolor, the otrA gene from S. rimosus M527 was cloned under the control of the strong ermE promoter. The resulting plasmid, pIB139-otrA, was introduced into S. coeficolor M145 by intergenedc conjugation, yielding the recombinant strain S. coelicolor M145-OA. As expected S. coelicolor M145-OA exhibited higher resistance levels specifically to OTC and aminoglycosides gentamycin, hygromycin, streptomycin, and spectinomycin. However, unexpectedly, S. coelicolor M14-~OA on solid medium showed an accelerated aerial mycelia formation, a precocious sporulation, and an enhanced actinorhodin （Act） production. Upon growth in 5-L fermentor, the amount of intra- and extracellular Act production was 6-fold and 2-fold higher, respectively, than that of the original strain. Consistently, reverse transcription polymerase chain reaction （RT-PCR） analysis revealed that the transcrip- tional level of pathway-specific regulatory gene acUl-orf4 was significantly enhanced in S. coelicolor M145-OA compared with in S. coelicolor M145.展开更多
For the sake of searching new methods of high-throughput screening of mutant strains,the strains were screened by applying the technology of metabolomics.Through using Fourier Transformation Infrared spectroscope(FTIR...For the sake of searching new methods of high-throughput screening of mutant strains,the strains were screened by applying the technology of metabolomics.Through using Fourier Transformation Infrared spectroscope(FTIR) accompanied with Principal Component Analysis(PCA) and Hierachical Cluster Analysis(HCA),the experiment successfully distinguished Streptomyces lydicus AS 4.2501 strains at different times of fermentation,and found the possible biomarkers when Streptomyces lydicus AS 4.2501 synthesized streptolydigin.The experiment,which attempted to use FTIR accompanied with Artificial Neural Network(ANN) to forecast Streptomyces lydicus AS 4.2501 mutation strains with different capacities of streptolydigin biosynthesis also obtained satisfying result.The results suggested that the combination of FTIR of metabolomics analysis with the data analysis of stoichiometric methods have prospective future in high-throughput screening of mutant strains.展开更多
基金supported by The National High Technology Development Project(863)(No. 2007AA09Z415)The National Natural Science Foundation of China(No.U0633008)
文摘Azalomycin F4a 2-ethylpentyl ester,a new 36-membered macrocyclic lactone antibiotic,was isolated from mangrove actinomycete Streptomyces sp.211726.Its structure was elucidated on the basis of spectroscopic data.The compound showed broad-spectrum antifungal activity and moderate cytotoxicity against human colon tumor cell HCT-116.
文摘Inoculation density has a marked effect on nodulation and N fixation in soybean (Glycine max L.). Therefore, we conducted this study to determine the optimal inoculation density of Bradyhizobium japonicum SAY3-7 (SAY3-7) and Streptomyces griseoflavus P4 (P4) for plant growth, nodulation, and N fixation, and to investigate the effect of co-inoculation on selected soybean cultivars, using the optimal inoculation density. Nitrogen fixation, in terms of an acetylene reduction activity value, was measured using a flame ionization gas chromatograph. In this study, low-density single inoculation with P4 (10<sup>5</sup> or 10<sup>6</sup> cells mL<sup>-1</sup>) was associated with the highest plant biomass, compared with normal- and high-density single inoculation with P4 (10<sup>7</sup> or 10<sup>8</sup> cells mL<sup>-1</sup>). Moreover, low-density single or co-inoculations with SAY3-7 and/or P4 produced the highest nodule biomass and highest nitrogenase activity, compared with single or dual inoculation at other inoculation densities. Therefore, we evaluated low-density co-inoculation with P4 and SAY3-7, at the rate of 10<sup>5</sup> cells mL<sup>-1</sup>, on selected soybean cultivars. Low-density co-inoculation increased the plant biomass, compared with un-inoculated plants. The effects of single and co-inoculation on nodulation did not differ significantly for any of the cultivars, except “Yezin-9” in the first experiment and “Shan Seine” in the second experiment. Low-density inoculation with both bacteria increased N fixation by 15% - 75% for seven of the cultivars in the first experiment and by 15% - 39% for three of the cultivars in the second experiment, compared with single inoculation with SAY3-7. Based on the overall results, we concluded that low-density co-inoculation with P4 and SAY3-7 gave improved plant growth and N fixation.
文摘(4S,5R)-5-Hydroxy-4-decanolide ,the proposed autoregulator from streptomyces Griseus was synthesized from an allyl alcohol 2,employ- ing the Sharpless kinetic resolution and the reaction of diethyl malonate with the epoxy compound as two key steps.
文摘A new degraded sesquiterpene was isolated from the marine actinomycete Streptomyces sp. 0616208. Its structure was elucidated as （1α; 4aα; 5α, 7β, 8aβ）-5, 8a-dimethyl-decahydrona- phthalene-1, 4a, 7-triol on the basis of spectroscopic data.
文摘Four groups of antibiotic activity compounds were separated and purified from the ethyl acetate fraction of a broth culture of Streptomyces herbaricolor HNS2-2.Trace analyses were performed and anti-microbial activities were determined. The antibiotic activity compounds were identified as quercetin dehydrate ①, p-hydroxyphenyl ②, 4’-hydroxyflavanone ③, and 3-hydroxyflavone ④ based on spectroscopic data. Compounds 1-4 showed significant antimicrobial activities against Staphylococcus aureus and the tobacco mosaic virus in vitro, suggesting their potential agricultural and medical applications.
基金Project supported by the National Natural Science Foundation of China(No.31772213)the Excellent Youth Fund of Zhejiang Province,China(No.LR17C140002)
文摘otrA resembles elongation factor G （EF-G） and is considered to be an oxytetracycline （OTC）-resistance determinant in Streptomyces rimosus. In order to determine whether otrA also conferred resistance to OTC and other aminoglycosides to Streptomyces coelicolor, the otrA gene from S. rimosus M527 was cloned under the control of the strong ermE promoter. The resulting plasmid, pIB139-otrA, was introduced into S. coeficolor M145 by intergenedc conjugation, yielding the recombinant strain S. coelicolor M145-OA. As expected S. coelicolor M145-OA exhibited higher resistance levels specifically to OTC and aminoglycosides gentamycin, hygromycin, streptomycin, and spectinomycin. However, unexpectedly, S. coelicolor M14-~OA on solid medium showed an accelerated aerial mycelia formation, a precocious sporulation, and an enhanced actinorhodin （Act） production. Upon growth in 5-L fermentor, the amount of intra- and extracellular Act production was 6-fold and 2-fold higher, respectively, than that of the original strain. Consistently, reverse transcription polymerase chain reaction （RT-PCR） analysis revealed that the transcrip- tional level of pathway-specific regulatory gene acUl-orf4 was significantly enhanced in S. coelicolor M145-OA compared with in S. coelicolor M145.
文摘For the sake of searching new methods of high-throughput screening of mutant strains,the strains were screened by applying the technology of metabolomics.Through using Fourier Transformation Infrared spectroscope(FTIR) accompanied with Principal Component Analysis(PCA) and Hierachical Cluster Analysis(HCA),the experiment successfully distinguished Streptomyces lydicus AS 4.2501 strains at different times of fermentation,and found the possible biomarkers when Streptomyces lydicus AS 4.2501 synthesized streptolydigin.The experiment,which attempted to use FTIR accompanied with Artificial Neural Network(ANN) to forecast Streptomyces lydicus AS 4.2501 mutation strains with different capacities of streptolydigin biosynthesis also obtained satisfying result.The results suggested that the combination of FTIR of metabolomics analysis with the data analysis of stoichiometric methods have prospective future in high-throughput screening of mutant strains.
