Genes for the biosynthesis of spinosyns: applications for yield improvement in Saccharopolyspora spinosa

Spinosyns A and D are the active ingredients in an insect control agent produced by fermentation of Saccharopolyspora spinosa. Spinosyns are macrolides with a 21-carbon, tetracyclic lactone backbone to which the deoxysugars forosamine and tri-O-methylrhamnose are attached. The spinosyn biosynthesis genes, except for the rhamnose genes, are located in a cluster that spans 74 kb of the S. spinosa genome. DNA sequence analysis, targeted gene disruptions and bioconversion studies identified five large genes encoding type I polyketide synthase subunits, and 14 genes involved in sugar biosynthesis, sugar attachment to the polyketide or cross-bridging of the polyketide. Four rhamnose biosynthetic genes, two of which are also necessary for forosamine biosynthesis, are located outside the spinosyn gene cluster. Duplication of the spinosyn genes linked to the polyketide synthase genes stimulated the final step in the biosynthesis — the conversion of the forosamine-less pseudoaglycones to endproducts. Duplication of genes involved in the early steps of deoxysugar biosynthesis increased spinosyn yield significantly. Journal of Industrial Microbiology & Biotechnology (2001) 27, 399–402. Received 31 May 2001/ Accepted in revised form 09 July 2001     

ESI-Q-TOF-MS直接进样法比较陕西五个不同地区丹参的化学成分差异（英文）

该研究采用ESI-Q-TOF-MS直接进样分析法对陕西商州、洛南、大荔、丹凤和铜川等五个地区丹参的化学成分进行了比较分析,通过丹参水溶性和脂溶性成分的质谱丰度差异评价了不同地区丹参化学成分含量的变化,对不同产地丹参的化学成分进行了鉴定,综合分析选出了最优的丹参种植产地。结果表明:五地丹参均含有丹参酮ⅡA、隐丹参酮、丹参酮Ⅰ、二氢丹参酮、丹参酚酮、次丹参醌、丹参醌Ⅱ等9种脂溶性化学成分和丹参素、咖啡酸、阿魏酸、迷迭香酸、原紫草酸、紫草酸、原儿茶醛、丹酚酸A、丹酚酸B等9种水溶性化学成分,其中丹参素钠、紫草酸、丹酚酸B和隐丹参酮的含量普遍较高,质谱丰度均大于30%。但是,随着种植环境不同,不同地区丹参的化学成分含量差异很大,如商州产丹参中含有较多具有生物活性的丹参酮类物质,其中丹参酮Ⅰ含量远远高于其他四个产地,质谱丰度达到72.6%,而其他地区丹参酮Ⅰ的质谱丰度为1.8%～11.3%。这表明丹参质量按照地区排序为商州>铜川>大荔>洛南>丹凤。该方法为中药药材质量评价提供了科学、可靠、便捷的途径,为药材规格等级的制定提供了新途径,为陕西丹参种植区域的选择提供了重要信息。     

多杀菌素生产菌种复壮方法及其效应的研究

用分离纯化复壮、淘汰法复壮及虫体复壮三种复壮方法对一株多杀菌素生产能力已经衰退的刺糖多孢菌进行复壮研究。结果显示：淘汰法复壮可显著提高菌株的杀虫毒力及多杀菌素的产量。通过红霉素抗性复壮筛选得到菌株杀虫死亡率达到100％,多杀菌素相对效价达1058．83％;通过NaCl抗性复壮筛选得到一菌株杀虫死亡率达到95％,多杀菌素相对效价达825．80％,因此淘汰法可作为有效的复壮方法。     

In Vitro Effects of Ginseng and the Seed of Zizyphus jujuba var. spinosa on Gut Microbiota of Rats with Spleen Deficiency

Ginseng and the seed of Zizyphus jujuba var. spinosa, which are traditional Chinese medicinal materials, were often used in ancient Chinese recipes as a pair of medicines. They can replenish the primordial qi and tonify the spleen. This study investigated the effects of ginseng and the seed of Zizyphus jujuba var. spinosa (GS) extract on gut microbiota diversity in rats with spleen deficiency syndrome (SDS). A total of 52 compounds (including 16 flavonoids, 35 saponins, and 1 alkaloid) were identified and analyzed from the GS extract by UPLC‐Q‐Orbitrap‐MS/MS. The GS extract significantly increased the relative abundance of Firmicutes and Bacteroidetes in rats with SDS but decreased that of Proteobacteria and Actinobacteria. At the genus level, the GS extract significantly increased the relative abundance of Lactobacillus and Bifidobacterium in rats with SDS but decreased that of Streptococcus, Escherichia‐Shigella, Veillonella, and Enterococcus. In addition, the GS extract influenced glucose and amino acid metabolism. In summary, the results showed that the GS extract changed the structure and diversity of gut microbiota in rats with SDS and balanced the metabolic process.     

Isolation and chemical modification of clerodane diterpenoids from Salvia species as potential agonists at the kappa-opioid receptor

The clerodane diterpenoid salvinorin A (1), the main active component of the psychotropic herb Salvia divinorum, has been reported to be a potent agonist at the kappa-opioid receptor. Computer modeling suggested that splendidin (2) from S. splendens, as well as related compounds, might possess similar activities. In the present study, this hypothesis was tested by determination of the binding properties of a series of structural congeners, compounds 2-8, at the mu-, delta-, and kappa-opioid receptors. However, none of these compounds showed significant binding to any of the opioid-receptor subtypes, thus disproving the above hypothesis. The novel compounds 7 and 8 were obtained semi-synthetically by selective modification of salvifarin (5), isolated from Salvia farinacea, upon epoxide-ring opening with AcOH in the presence of indium(III) triflate. Also, the X-ray crystal structure of salvifaricin (6; Fig.), obtained from S. farinacea, was determined for the first time and used, in combination with in-depth NMR experiments, to elucidate the absolute configurations of the new products. Our experiments demonstrate that the relatively well-accessible diterpenoid 6 could be used as starting material for future studies into the structure-activity relationship at the kappa-opioid receptor.     

丹参氮、磷肥效效应及最佳施肥模式研究

在陕西省商州市山阳县不同肥力土壤上,采用N、P二因素五水平最优设计,进行了丹参氮、磷优化配方施肥模式研究的多点田问试验。根据田间试验结果,求得不同土壤肥力水平下的N、P肥效反应方程,根据方程提出丹参不同产量水平的N、P合理配比和肥料用量。寻优结果表明,在山阳低肥力土壤目标产量10000～11500kg／hm^2之间的施氮为88．17～165．7kg／hm^2,施磷(P2O4)为88．18～165．7kg／hm^2;中肥力土壤目标产量在11000～14000kg／hm^2之间的施N量为108．5～187．4kg／hm^2,施磷(P2O5)为105．1～179．5kg／hm^2;高肥力土壤目标产量在20000～25000kg／hm^2之间的施N量为85．4～173．1kg／hm^2,施磷(P2O5)为121．95～179．01kg／hm^2。合理施用N、P肥有利于提高丹参产量,但过量施肥会造成丹参减产。