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1.
筛选具有较好生物学功能的芽胞杆菌(Bacillus),用以改善池塘养殖过程饲料等有机物降解、抑制水体中的病原菌,对从健康养殖鱼虾塘水体中分离的菌株,进行生化试验和16S rDNA序列分子鉴定;通过产酶、耐酸、耐高温试验,抑菌试验以及安全性试验研究分离菌株的生物学功能。试验共筛选出8株细菌,经生化试验及16S rDNA序列的分子鉴定,确定菌株ZHX17、ZHX18、ZHX31为贝莱斯芽胞杆菌(Bacillus velezensis),菌株ZHX14、ZHX15为地衣芽胞杆菌(Bacillus licheniformis)、菌株NSX4、NSX7、NSX9为枯草芽胞杆菌(Bacillus subtilis)。试验结果表明,8株芽胞杆菌均具有较强的耐酸、耐高温特性,其中3株贝莱斯芽胞杆菌具有较强的分泌淀粉酶、纤维素酶、蛋白酶的能力,抑菌效果好于其他5株芽胞杆菌。安全性试验结果表明,8株芽胞杆菌对草鱼、罗非鱼相对安全。8株芽胞杆菌同时具备分泌淀粉酶、纤维素酶和蛋白酶3种胞外酶的能力,其中贝莱斯芽胞杆菌具有较强的病原菌抑菌能力,可以作为病原拮抗益生菌做进一步研究。  相似文献   

2.
灰肉红菇(Russula griseocarnosa)是岭南地区著名的野生食药用真菌。本研究通过组织分离的方法,从灰肉红菇子实体分离获得一株内生真菌,经形态学和分子生物学分析鉴定为爪哇虫草(Cordyceps javanica)。以牛津杯抑菌圈法及二倍稀释法测试了其菌丝体胞内和胞外多糖粗提物对金黄色葡萄球菌(Staphylococcus aureus)和铜绿假单胞菌(Pseudomonas aeruginosa)的抑菌活性。结果表明:水溶性胞内、胞外多糖对金黄色葡萄球菌及铜绿假单胞菌均具有抑菌活性,最低抑菌浓度(MIC)为37.5 mg/mL。  相似文献   

3.
通过比较四种品系小鼠对炭疽芽胞杆菌(Bacillus anthracis)(简称炭疽杆菌)弱毒株芽胞的敏感性,确定炭疽杆菌弱毒株芽胞攻毒合适的动物模型。采用炭疽杆菌弱毒株A16Q1(pXO1-、pXO2+)和A16PI2(pXO1+、pXO2-)的芽胞对四种品系小鼠(DBA/2、KM、ICR和BALB/c)进行腹腔攻毒,记录小鼠死亡时间,计算LD50、绘制存活曲线并统计分析。运用较敏感的KM小鼠研究不同canSNP基因型毒素缺陷株(含pXO2拷贝数不同)芽胞的毒力差异。利用更为敏感的DBA/2小鼠评价S-层蛋白BA3338对荚膜缺陷株芽胞毒力的影响。结果表明,在四种品系小鼠中,毒素缺陷株芽胞的毒力均高于荚膜缺陷株芽胞的毒力。DBA/2小鼠对炭疽杆菌弱毒株芽胞的剂量依赖关系最好,最为敏感,其次是KM小鼠,而ICR小鼠和BALB/c小鼠对炭疽杆菌弱毒株芽胞不敏感。确定了DBA/2小鼠和KM小鼠在炭疽杆菌弱毒株芽胞研究中的适用性。使用KM小鼠评价了不同canSNP基因型炭疽杆菌芽胞的毒力差异,结果表明,不同canSNP基因型炭疽杆菌由于所含pXO2质粒拷贝数的差异导致芽胞的毒力不同。使用DBA/2小鼠评价了S-层蛋白BA3338缺失对炭疽杆菌芽胞毒力的影响,表明BA3338基因的缺失导致炭疽杆菌芽胞毒力降低。  相似文献   

4.
从鸟类苔藓和草叶巢材中分离出6株优势细菌和8株放线菌,采用传统表观型特征观察和16SrRNA基因序列分析法对其进行菌种鉴定。结果表明:草叶巢材中的优势细菌分别为霍氏肠杆菌(Enterobacter hormaechei)、麝香石竹假单胞菌(Pseudomonas caryophyUi)和丁香假单胞菌(Pseudomonas syringae);苔藓巢材中的优势细菌分别为苏云金芽胞杆菌(Bacillus thuringiensis)、阴沟肠杆菌(Enterobacter cloacae)和马氏棒杆菌(Corynebacteriu matruchotii);从2种巢材中分离出的8株放线菌均为链霉菌属(Streptomyces),其中4株分另q为金色链霉菌(Streptomyces aureus)、红色淡紫灰链霉菌(Streptomyces rubrolavendulae)、胶样链霉菌(Streptomyces gelaticus)和灰色链霉菌(Streptomyces griseus),另外4株链霉菌有待于进一步鉴定。  相似文献   

5.
筛选得到对慢性创面中铜绿假单胞菌(Pseudomonas aeruginosa)和金黄色葡萄球菌(Staphylococcus aureus)生物膜形成具有抑制作用的乳杆菌(Loctobacillus)。测定不同种乳杆菌对铜绿假单胞菌和金黄色葡萄球菌双菌生物膜量、生长及群体感应信号分子AI-2的影响,并采用主成分分析和菌株特性综合分析确定效果最佳的菌株,最后通过荧光定量PCR的方式探究该菌株对生物膜和群体感应相关基因表达的影响。结果表明,植物乳杆菌(Lactobacillus plantarum)、卷曲乳杆菌(Loctobacillus crispatus)、嗜酸乳杆菌(Loctobacillus acidophilus)、鼠李糖乳杆菌(Loctobacillus rhamnosus)、瑞士乳杆菌(Loctobacillus helveticus)、短乳杆菌(Loctobacilkus brevis)具有不同程度的抑菌、抑制生物膜形成的能力,且同种不同株的乳杆菌抑制生物膜形成的能力也有所差异。其中,植物乳杆菌CCFM233产生的AI-2信号分子较多,具有良好的抑菌能力,可使致病菌生物膜形成量降低,铜绿假单胞菌的LasRrhlI基因表达水平和金黄色葡萄球菌的SarA基因表达水平显著下调。本研究旨在揭示植物乳杆菌CCFM233具有抗铜绿假单胞菌和金黄色葡萄球菌感染的潜力,为其应用于慢性创面敷料提供参考。  相似文献   

6.
对3种具有土壤中多种重金属污染修复和病虫害防治功能的光合细菌(Photosynthetic bacteria,PSB,包括Rhodobacter sphaeroides H菌株、Rhodopseudomonas palustris N菌株和Rhodospirillium rubrum M菌株)、枯草芽胞杆菌(Bacillus subtilis, BS)和植物乳酸杆菌(Lactobacillus plantarum, LP)进行混合培养,利用单因素和响应面试验优化培养基配方以及培养条件。确定功能菌混合培养的最佳条件:以光合细菌培养基为基础培养基,外加碳源为10 g/L蔗糖、氮源为1.25 g/L硫酸铵、培养温度为31.5 ℃、初始pH值为7.1、接种量为接种后的初始培养活菌数1.90×109cfu/mL、培养时间为28.0 h。通过功能菌的加性模型法、生长动力学以及混合培养的生长关系分析表明,光合细菌、枯草芽胞杆菌和植物乳酸杆菌的生长均存在互惠互利关系。  相似文献   

7.
昆虫肠道微生物对其寄主的生长发育、营养代谢、免疫以及农药抗性等方面都发挥着重要作用。为研究斜纹夜蛾Spodoptera litura幼虫肠道细菌的多样性,并为其功能验证做准备,本文利用传统微生物分离纯培养方法从斜纹夜蛾4龄幼虫肠道中共分离鉴定得到10株细菌,分别为属于变形菌门(Proteobacteria)的脱氮假单胞菌(Pseudomonas denitrificans),不动细菌(Acinetobacter sp.),肺炎克雷伯氏菌(Klebsiella pneumoniae)和肠杆菌(Enterobacter sp.);属于厚壁菌门(Firmicutes)的鸡葡萄球菌(Staphylococcus gallinarum),蒙氏肠球菌(Enterococcus mundtii),蜡样芽胞杆菌(Bacillus cereus)和枯草芽胞杆菌(Bacillus subtilis)以及放线菌门(Actinobacteria)的微杆菌(Microbacteriums sp.)和乳酪棒杆菌(Corynebacterium casei)。变形菌门和厚壁菌门是斜纹夜蛾肠道可培养细菌中的优势菌群。功能验证实验表明肠杆菌具备纤维素降解能力,微杆菌具备很强的苯酚降解能力。本研究为未来深入研究斜纹夜蛾肠道微生物的功能提供了方向和菌株材料。  相似文献   

8.
探讨耐亚胺培南铜绿假单胞菌的耐药性及其产超广谱β-内酰胺酶基因型。收集2011年7月至2013年12月上海市中医药大学附属曙光医院临床分离的铜绿假单胞菌共1 125株,筛选亚胺培南耐药株,常规纸片法检测其耐药性,并用E-test检测金属β-内酰胺酶(MBL),采用PCR法检测耐药基因型。结果显示,1 125株铜绿假单胞菌中耐亚胺培南铜绿假单胞菌共计617株,占54.8%;亚胺培南敏感铜绿假单胞菌共计508株,占45.2%。617株亚胺培南耐药铜绿假单胞菌100%为多重耐药,而亚胺培南敏感铜绿假单胞菌的多重耐药率仅为13.78%,明显较前者低(χ2=871.15,P<0.05);亚胺培南耐药的铜绿假单胞菌中MBL表型阳性共126株,阳性率为15.4%,94株(74.60%)表现为VIM-2阳性,10株(7.94%)表现为IMP-1阳性,1株检出OXA-10,〖WTBZ〗且该例菌株同时表达VIM-2。临床分离的耐亚胺培南的铜绿假单胞菌多为多重耐药,其产MBL的主要基因型是VIM-2。  相似文献   

9.
广东南岭森林土壤中蕴藏着丰富的生物资源,但对其中的可培养细菌种类仍缺乏系统了解。本研究采用贫营养型的R2A培养基和富营养型的TSA培养基对南岭森林土壤中细菌进行了分离,获得细菌408株,分别从属于厚壁菌门、变形菌门、放线菌门和拟杆菌门的35属。其中的优势类群为厚壁菌门,占分离总数量的71%。在属水平,芽胞杆菌及其近缘属为优势类群。除芽胞杆菌外,假单胞菌、伯克霍尔德氏菌草酸杆菌科Collimonas属和罗丹诺杆菌科Dyella属是分离获得的主要类群。R2A培养基在分离革兰氏阴性的变形菌门菌株方面表现出一定的偏好性,而TSA培养基分离得到的更多为快速生长的芽胞杆菌及其近缘的革兰氏阳性细菌。发现了15属的菌株具有一定的水解酶活性,大多表现出对淀粉和牛奶的水解活性,对有机磷的水解性能优于对无机磷的水解。降解纤维素的菌株则主要集中于芽胞杆菌及其近缘属中。发现了潜在新物种26株,分布于芽胞杆菌、Dyella、类芽孢杆菌等9属中。本研究仅使用了两种营养类型的培养基,进一步借助培养组学技术有望能更加全面反映南岭森林土壤中的可培养微生物多样性。  相似文献   

10.
垃圾微生物除臭剂的筛选、复配及其培养条件的优化   总被引:1,自引:0,他引:1  
为了获取作为除臭微生物制剂的候选菌株,从垃圾渗滤液中分离筛选了4株具有对硫化氢和氨气高效降解菌株,分别标记为CC3、CC7、CC13和CC16。通过形态、生理生化和16S rDNA序列分析,分别鉴定为乳酸片球菌(Pediococcus acidilactici)、巨大芽胞杆菌(Bacillus megaterium)、嗜酸乳杆菌(Lactobacillus acidophilus)、粪产碱杆菌(Alcaligenes faecalis),并确定复配菌剂的除臭能力。实验结果表明:菌株CC7、CC13和CC16组成的复配组合除臭效率最优,其最佳复配比例为1:1.5:0.5,接种量为5%,培养温度为30 ℃,初始培养基pH值为6.5,培养时间为60 h时,对氨气和硫化氢的去除率为最大值,可达到83.56%和70.25%。  相似文献   

11.
《环境昆虫学报》2014,(5):790-804
综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生(宾主共栖和异种共栖)、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌(原生动物、细菌、真菌和放线菌)和外生菌(蚁巢伞菌等)间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用(如纤维素酶)及今后研究物种间的协同进化提供了基础资料。  相似文献   

12.
New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn2NPSCH2CH2Sa(P-Sa) (Bn = benzyl, 4), Bn2NPSCHCHSa(CH2)3CaH2(P-Sa)(Ca-Sa) (6) and Bn2NP(4-XC6H4OMe)2 (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)2] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl2Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the νCO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The 1JPRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the 1JPSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh3. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh3.  相似文献   

13.
Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.  相似文献   

14.
The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.  相似文献   

15.
To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.  相似文献   

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18.
The ability of partially purified human and guinea-pig haematogenous cell populations, when cultured in vitro, to metabolise arachidonic acid (AA) has been studied. Supernatants from 24 hour cell culture have been subjected to analysis for products of AA metabolism by gas chromatography with electron-capture detection.The cell types studied were human peripheral blood monocytes (both glass adherent and non-adherent), neutrophils, eosinophils and leukemic leucocytes; thoracic duct lymphocytes and lung alveolar macrophages. From the guinea-pig, induced and non-induced macrophage or neutrophil enriched peritoneal exudate populations, lymph node cells, peritoneal eosinophils and peripheral blood platelets were examined. Supernatants were assayed for the presence of PGE2, PGD2, PGF, TXB2 and 6-keto-PGF. In all types studied PGE2 and TXB2 were the major products formed. The identification of PGE2 and TXB2 was confirmed by GC/MS with multiple ion monitoring.The results have been compared with other reports and their possible significance discussed in relation to the proposed role of prostaglandins as mediators and modulators in immunopathology.  相似文献   

19.
Allergic asthma can be precipitated by many factors. For the atopic person, fungus, pollen, dust mites, cockroach antigens, and diesel exhaust are all agents that may trigger an allergic attack. Cytokines and chemokines are integral mediators of fungal asthma. From the earliest time points, they recruit and activate the cells required for the clearance of fungus as well as being critical factors involved in the immunopathology of this disease. In the final analysis, it is clear that these mediators can act to the benefit or the detriment of the host.  相似文献   

20.
In spite of the many studies on protein modifications by reactive species, knowledge about the products resulting from the oxidation of protein-aromatic residues, including protein-derived radicals and their stable products, remains limited. Here, we compared the oxidative modifications promoted by peroxynitrite and myeloperoxidase/hydrogen peroxide/nitrite in two model proteins, ribonuclease (6Tyr) and lysozyme (3Tyr/6Trp). The formation of protein-derived radicals and products was higher at pH 5.4 and 7.4 for myeloperoxidase and peroxynitrite, respectively. The main product was 3-nitro-Tyr for both proteins and oxidants. Lysozyme rendered similar yields of nitro-Trp, particularly when oxidized by peroxynitrite. Hydroxylated and dimerized products of Trp and Tyr were also produced, but in lower yields. Localization of the main modified residues indicates that peroxynitrite decomposes to radicals within the proteins behaving less specifically than myeloperoxidase. Nitrogen dioxide is emphasized as an important protein modifier.  相似文献   

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