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周林朱爽潘敏芬蔡泽加许尧滨 《现代生物医学进展》2011,11(8):1436-1439
目的:采用双亲灭活原生质体技术制备粘质沙雷氏菌和红曲霉的跨界产色素融合子,并测定其抑菌活性。方法:经0.2%溶菌酶处理获得粘质沙雷氏菌的原生质体并热灭活;经混合酶(0.8%溶菌酶+1.2%蜗牛酶+1.6%纤维素酶)处理获得红曲霉的原生质体并紫外灭活;用含25%PEG的原生质体融合剂进行促融合与再生。观察融合子的菌落形态和色素合成能力,测定融合子色素提取物对金黄色葡萄球菌的抑制活性。结果:在优化条件下,粘质沙雷氏菌原生质体的形成率为92.58%,红曲霉原生质体形成数约为106个/mL,两菌原生质体灭活率均为100%。共获得13个融合子,9个能产红色素,融合率为1×10-5%。其中8个融合子的95%乙醇提取物对金黄色葡萄球菌表现出不同程度的抑制。结论:采用双亲灭活原生质体技术,能够制备具有抑菌活性的粘质沙雷氏菌和红曲霉的跨界产色素融合子。 相似文献
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用扫描电镜和透射电镜对粘质沙雷氏菌(Serratia marcescens)的临界点干燥标本和负染标本作了观察,均可见到细胞表面常有一至二个直径为0.12~0.24μm的颗粒。在超薄切片中颗粒则有两种不同的结构:一种是外膜泡(Outer membrane vesicle);另一种是致密体(Dense body)。致密体可能是一种分泌性颗粒,它既不是内部的贮存物,也不似外部进来的异物。它们看来形成于细胞质内后分泌到细胞外。在细菌中这是一种罕见现象。有关致密体的化学性质和功能尚不清楚。文中指出粘质沙雷氏菌的纲胞表面也具有茂密的菌毛(Pili)。 相似文献
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目的:确定菌株S418产生灵菌红素的最优培养基配方及其的分类地位。方法:以花生粉为基础培养基,通过单因素试验和四因素三水平正交试验筛选出了菌株S418产灵菌红素的最佳培养基配方;根据该菌株的16S rRNA基因序列系统发育树分析初步确定了菌株S418的分类地位。结果:培养基最优配方为:花生粉2%,花生油0.5%,L-脯氨酸1%,硫酸镁0.025%。在28℃、pH7.5、250r/min振荡培养24h,灵菌红素产量达67.92mg/L。菌株S418初步鉴定为粘质沙雷氏菌(Serratia marcescensS418)。结论:花生粉培养基是一种适合粘质沙雷氏菌产灵菌红素的优良培养基。 相似文献
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目的:通过对产脂肪酶粘质沙雷氏菌发酵条件的优化,使其酶活力得到大幅度提高。方法:用响应面法对产脂肪酶粘质沙雷氏菌的发酵产酶培养条件进行了优化。首先通过逐因子实验考察了该菌株产酶所需的最适碳源和氮源,在此基础上通过Plackett-burman法设计实验,考察了几种因素对产酶影响的大小,然后用最陡爬坡实验逼近以上几种因子的最大响应区域后,采用Box-Behnken设计25组实验,并利用Design-Expert对实验结果进行二次回归分析。结果:对产酶具有显著效应的4个因素为:蛋白胨、CaCl2、吐温、大豆油。实验优化到最佳的产酶条件为:糊精1%,蛋白胨0.7%、CaCl20.3%、吐温-80 1.68%、大豆油1.81%、K2HPO40.05%、MgSO40.05%、FeSO40.1%。结论:优化后发酵液上清的脂肪酶活力可达97.52U/ml,比优化前提高了10倍。 相似文献
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本文对粘质沙雷氏菌发酵生产D-乳酸进行了研究。以粘质沙雷氏菌G1(Serratia marcescens G1)为出发菌种,摇瓶试验确定了发酵培养方式:前12 h为菌体生长阶段,有氧培养,温度28℃,pH值7.0;后36 h为D-乳酸合成积累阶段,无氧培养,温度44℃,pH值6.0。且发现使用葡萄糖为碳源时更有利于D-乳酸的合成积累。采用缺失2,3-丁二醇合成能力的基因工程菌株R1为出发株,经筛选后得到耐受较高浓度乳酸盐的菌株R150,以R150为发酵菌种,在3.7 L发酵罐上采用两阶段发酵法,并通过增加起始菌体浓度的方法,发酵生成的D-乳酸浓度达到83.5 g/L,光学纯度达到98.9%。本研究成果为使用粘质沙雷氏菌发酵生产D-乳酸的深入研究打下了基础。 相似文献
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灵菌红素是由微生物产生的一种红色次级代谢产物,因其具有抗菌、抗癌和抗疟疾等功效,受到了生物医药领域的广泛关注。微生物发酵是当前产灵菌红素的主要方法,分离筛选高产灵菌红素的微生物、优化发酵条件是提高灵菌红素产率的重要途径。本研究从深圳湾筛选出一株含有红色色素的菌株,并基于16S rRNA基因序列对该菌株进行了系统发育分析和物种鉴定。紫外可见光全波长扫描和HPLC-MS图谱分析证明,该菌株所产红色色素为灵菌红素。进一步通过单因素试验和正交优化法优化了该菌产灵菌红素的发酵条件和发酵培养基组分。系统发育分析表明,该菌株为一株海洋粘质沙雷氏菌(Serratia marcescens),并将其命名为S. marcescens SOCE 001。产灵菌红素的最佳发酵条件为:温度28 ℃、振荡培养转速220 r/min、培养基pH 7。发酵培养基最佳组合为:果糖添加量2 g/L、蛋白胨添加量10 g/L,MgSO4添加量2 g/L。优化发酵条件后,经24 h培养, 灵菌红素产量可达2.468 g/L。 相似文献
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以黏质沙雷菌jn01株为宿主菌,从环境污水中分离噬菌体,经反复挑取噬菌斑,获得1株纯化的噬菌体,定名为SmPjn。SmPjn在双层琼脂平板上可形成直径约2mm,圆形、透明的噬菌斑,边缘清晰。透射电镜观察,该噬菌体有一短尾,长(7± 1.25)nm,头部长、宽分别为(58± 2.16)nm×(55±0.47)nm,属短尾噬菌体科(Podoviridae)。可裂解jn01以外的2株黏质沙雷菌;与宿主菌共培养4h后的最佳感染复数为1;一步生长曲线表明该噬菌体的潜伏期约为50min,平均爆发量约为1125pfu/cell。基因组为大于27 kb的DNA,可分别被HindⅢ、EcoRⅠ切成11和9个电泳片段。本报道为国内首次分离黏质沙雷菌短尾噬菌体。 相似文献
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Stimulation and inhibition of polymorphonuclear leukocytes phagocytosis by lipoamino acids isolated from Serratia marcescens 总被引:1,自引:0,他引:1
Yoshiko Miyazaki Shiro Oka Hisako Hara-Hotta Ikuya Yano 《FEMS immunology and medical microbiology》1993,6(4):265-271
Abstract The role of the lipoamino acids (serratamolide and ornithine lipid), membrane lipid components of Serratia marcescens , was examined in phagocytosis and phagosome-lysosome fusion of human peripheral polymorphonuclear leukocytes. A mutant strain of Serratia marcescens (NS 38-09) lacking serratamolide was actively phagocytosed by human PMN, while the wild-type strain (NS 38) producing serratamolide was more resistant to phagocytosis by human PMN. Phagocytosis of killed Staphylococcus aureus coated with lipoamino acid (serratamolide), showed that they were more resistant to phagocytosis by PMN, while the cells coated with ornithine lipid or serratamic acid were phagocytosed more actively. Staphylococci coated with phosphatidylethanolamine or phosphatidylglycerol had no significant effect on phagocytosis by PMN. Phagosome-lysosome fusion by PMN labelled with acridine orange was examined by fluorescence microscopy. The fusion indices of lipoamino acid-coated staphylococci were the same as that of controls. Further, ornithine lipid-coated staphylococci stimulated the release of superoxide anion from PMN slightly, but serratamolide did not. These results suggested that serratamolide may contribute to the virulence of S. marcescens in vitro. 相似文献
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为获得高产MonacolinK的红曲菌菌株,将经农杆菌介导转化获得的携带潮霉素抗性基因且以甘油为原料液态发酵高产MonacolinK的发白红曲菌H2和以大米为原料固态发酵产Monaco-1inK的烟色红曲菌9908作为亲本,对其原生质体分别进行热灭活及紫外灭活,然后对灭活双亲用PEG作融合剂进行原生质体融合。从融合子中选出有潮霉素抗性的突变株,通过发酵与亲本对比,筛选得到一株以大米为原料固态发酵高产MonacolinK的融合株F12.11,其MonacolinK产量达到8.73mg/g;较发白红曲菌H2与烟色红曲菌9908分别提高了100.23%和48.98%;一株以甘油为原料液态发酵高产MonacolinK的融合株F13-2,其MonacolinK的产量达到1752.46mg/L,较发白红曲菌H2与烟色红曲菌9908分别提高了32.98%和1979.33%。 相似文献
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考察了不同的短链有机酸对粘质沙雷氏菌合成2,3-丁二醇的影响,结果表明乙酸、乳酸、丙酮酸、琥珀酸、延胡索酸和柠檬酸均能在一定程度上提高2,3-丁二醇的产量,其中乙酸的效果最为明显,在基础培养基中添加6g/L乙酸,与对照相比,2,3.丁二醇的产量提高了91.06%,此外菌体干重也提高了58.28%。为了揭示其中的调控机制,构建了启动子:lacZ融合报告载体,fncz活性测定显示六种有机酸均可提高报告基因B.半乳糖苷酶的表达,其中乙酸可提高B.半乳糖苷酶活性近4倍,暗示六种有机酸促进2,3-丁二醇的合成可能与诱导该合成途径相关基因的表达有关。 相似文献
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Qun Yan Peter Hoi-Fu Yu Hua-Zhong Li 《World journal of microbiology & biotechnology》2005,21(6-7):1255-1258
Summary A simplified HPLC detection method for tetrodotoxin and its biosynthesis by Serratia marcescens was investigated. With 0.04% phosphoric acid as mobile phase, tetrodotoxin could be detected by HPLC equipped with a UV detector
at a lower limit of 1 mg/l. After being cultivated in an improved ORI medium for a few days, Serratia marcescens was found to be capable of producing tetrodotoxin, and this was confirmed by both HPLC, and mouse bioassay. 相似文献
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为提高红曲色素的液态发酵水平,降低生产成本,采用Plackett-Burman试验与Box-Benhnken试验对红曲霉MY-03液态发酵生产红曲色素的工艺条件进行了优化,获得了最佳工艺条件:葡萄糖50 g/L、蛋白胨58.07 g/L、Mg SO4 2 g/L、Na NO3 2g/L、Mn SO4 0.3 g/L、Zn SO4 0.1 g/L、装瓶量50.8 m L、接种量10.0%(V/V),于150 r/min、30℃恒温培养7 d,红曲色素色价可达342.24±2.88 U/m L,比基础培养基提高了86.9%。 相似文献
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S. J. Horn M. Sørlie G. Vaaje-Kolstad A. L. Norberg B. Synstad K. M. Vårum 《Biocatalysis and Biotransformation》2013,31(1-2):39-53
Serratia marcescens produces three chitinases, ChiA, ChiB and ChiC which together enable the bacterium to efficiently degrade the insoluble chitin polymer. We present an overview of the structural properties of these enzymes, as well as an analysis of their activities towards artificial chromogenic chito-oligosaccharide-based substrates, chito-oligosaccharides, chitin and chitosan. We also present comparative inhibition data for the pseudotrisaccharide allosamidin (an analogue of the reaction intermediate) and the cyclic pentapeptide argadin. The results show that the enzymes differ in terms of their subsite architecture and their efficiency towards chitinous substrates. The idea that the three chitinases play different roles during chitin degradation was confirmed by the synergistic effects that were observed for certain combinations of the enzymes. Studies of the degradation of the soluble heteropolymer chitosan provided insight into processivity. Taken together, the available data for Serratia chitinases show that the chitinolytic machinery of this bacterium consists of two processive exo-enzymes that degrade the chitin chains in opposite directions (ChiA and ChiB) and a non-processive endo-enzyme, ChiC. 相似文献