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1.
刘天贵  胡尚勤   《微生物学通报》2000,27(5):349-352
报道了地衣芽孢杆菌对不同抑制剂的反应。结果表明,当pH在7.0时,链霉素浓度为500μg/mL,青霉素浓度1000μg/mL,头孢唑啉钠浓度为500μg/mL时对地衣芽孢杆菌有明显抑制作用。这对正确使用地衣芽孢杆菌制剂(整肠生)提供了可靠的理论依据。  相似文献   

2.
微生态系统中地衣芽孢杆菌消长的研究   总被引:1,自引:1,他引:0  
采用不同接种培养方法,研究了地衣芽孢杆菌在微生态系统的消长状况.结果表明,在健康人体内该菌能迅速增殖,菌数为1.49×108~1.83×108个·g-1,并能较长时间定植下来,30d后菌数为1.27×107~1.51×107个·g-1.在病人体内增殖相对较慢些,菌数为1.40×108~1.67×108个·g-1,30d后菌数为1.15×107~1.31×107个·g-1.在人工模拟微生态系统中,当pH为5.0~9.0,营养物为食物匀浆培养基、牛肉膏蛋白胨培养基时,其菌数为3.05×108、3.42×108个·ml-1.  相似文献   

3.
本文重点在于提高酪酸梭状芽孢杆菌活菌数量,降低发酵培养基成本。通过对发酵培养基中不同碳源、氮源、生长因子等进行单因素研究,得到最佳培养基组成:可溶性淀粉10/L,豆粕(中性蛋白酶水解3h)20g/L,玉米浆3g/L。用此培养基在37℃培养24h,采用高层半固体琼脂试管法对酪酸梭状芽孢杆菌进行活菌计数,活菌数可达8.2×10^8cfu/mL.培养基中添加K2HPO45g/L、MgSO4·7H2O0.2g/L、MnSO3·H2O0.2g/L培养32h时,酪酸梭状芽孢杆菌芽孢转化率可达95%。  相似文献   

4.
地衣芽孢杆菌是一种革兰氏染色呈阳性的益生菌,俗称整肠生,其细胞呈杆状排列、单生,能产生近中生的芽孢,形态为椭圆状,孢囊稍膨大。它在生活中主要应用于饲料添加、医药、工业等方面,本文综述了地衣芽孢杆菌的主要应用。  相似文献   

5.
整肠生是应用二十多年的地衣芽胞杆菌活菌制剂,已有大量的研究报道其临床有效性和安全性。地衣芽胞杆菌大量分泌种类丰富的消化酶,通过抑制肠道有害菌生长和促进有益菌增殖调节肠道菌群,并产生杆菌肽、地衣素和乙酸等生物活性物质发挥益生作用。本文总结了益生菌的益生特点,并重点分析了芽胞杆菌的益生特点,归纳了整肠生的作用机制与临床研究现状,揭示了其在肝脏疾病、溃疡性结肠炎、肠易激综合征、幽门螺旋杆菌感染以及病毒感染等疾病中的治疗作用,并对整肠生未来的临床应用方向进行了展望。  相似文献   

6.
从皖北盐碱地土样中分离到 0 1 1菌株 ,对其进行了菌种鉴定以及胞外碱性蛋白酶的初步研究。结果表明 :0 1 1菌株符合地衣芽孢杆菌种的特征 ,但该菌芽孢端生、孢囊膨大、中度耐盐、高度耐碱 ,可在NaCl浓度为 1 3%和pH1 1的培养基中生长 ,这些特征又不同于该种几个模式株 ,因而将 0 1 1菌株鉴定为地衣芽孢杆菌的一个亚种 ,命名为地衣芽孢杆菌砀山亚种(Bacilluslicheniformissubsp .dangshanensis)。该菌在发酵培养基中能产生较高产量的胞外碱性蛋白酶 ( 72 5u/mL)。酶的最适作用条件 :60℃、pH9.0 ,该酶在pH6.0~ 1 1范围内稳定  相似文献   

7.
一株地衣芽孢杆菌碱性蛋白酶的研究Ⅰ.   总被引:17,自引:1,他引:16  
从皖北盐碱地土术中分离到011菌株,对其进行了菌种鉴定以及胞外碱性蛋白酶的初步研究。结果表明:011菌株符合地衣芽孢杆菌种的特征,但该菌芽孢端生、孢囊膨大、中度耐盐、高度耐碱,可在NaCl浓度为13%和pH11的培养基中生长,这些特征又不同于该种几个模式株,因而将011菌株鉴定为地衣芽孢杆菌的一个亚种,命名为地衣芽孢杆菌砀山亚种(Bacillus licheniformis subsp.dangshanensis)。该菌在发酵培养基中能产生较高产量的胞外碱性蛋白酶(725u/mL)。酶的最适作用条件:60℃、pH9.0,该酶在pH6.0-11范围内稳定。  相似文献   

8.
整肠生菌细胞融合子的发酵及产物分析研究   总被引:3,自引:0,他引:3  
利用细胞融合技术,将整肠生菌高芽孢形成率的菌株B1和低芽孢形成率和菌数产量都低的菌株B2进行细胞融合,经芽孢数测定和发酵产物测定与遗传分析鉴别,得到了代谢产物量不同于亲本和芽孢形成率高的新菌株B1-2。该融合子乳酸产量是亲本的1.2~1.6倍,丁二醇产量是亲本的1.5~2.3倍。芽孢形成率是亲本的1.2~2.1倍。  相似文献   

9.
从皖北盐碱地土样中分离到 011菌株 ,对其进行了菌种鉴定以及胞外碱性蛋白酶的初步研究。结果表明 :011菌株符合地衣芽孢杆菌种的特征 ,但该菌芽孢端生、孢囊膨大、中度耐盐、高度耐碱 ,可在NaCl浓度为 13%和pH11的培养基中生长 ,这些特征又不同于该种几个模式株 ,因而将 011菌株鉴定为地衣芽孢杆菌的一个亚种 ,命名为地衣芽孢杆菌砀山亚种(Bacilluslicheniformissubsp .dangshanensis)。该菌在发酵培养基中能产生较高产量的胞外碱性蛋白酶 ( 72  相似文献   

10.
生物素对地衣芽孢杆菌生长和乳酸形成的影响   总被引:3,自引:0,他引:3  
生物素对地衣芽孢杆菌生长和乳酸形成的影响胡尚勤(重庆师范学院生物系重庆630047)地衣芽孢杆菌(Baciluslicgeniformis)是我国90年代首次从正常待产妇阴道拭子分离出来的一个无毒新菌株。现在国内已经用它来生产“整肠生”活菌剂。它是一...  相似文献   

11.
The molecular structure of the intron of the mitochondrial gene coding for cytochrome oxidase susbunit II has been investigated by sequence analysis in eight angiosperm orders. Comparison of the overall primary structure of the intron, made with respect to Magnoliales, the ancestor group of all the angiosperms, reveals a high conservation among dicot plants. On the contrary, the introns of both ancient and advanced monocot orders show relevant divergences represented by insertions and deletions in conserved specific regions of the introns. As a consequence of some of these rearrangements, a structure similar to a transposable element is generated in advanced monocots. This specific structure, common in all the analyzed species of Poales, seems to be generated by a stepwise process and it is not dependent on an insertion event.  相似文献   

12.
13.
Summary Hepatopancreas from Acellus intermedius, a small freshwater isopod, was examined by light and electron microscopy. Of particular interest are the two cell types present in the hepatopancreas. Their ultrastructural features indicate that the major role of the large alpha cells is to absorb material from the lumen as well as secrete materials into the lumen while the major role of the small beta cells is to store the absorbed materials as well as break down stored materials before transport.  相似文献   

14.
N. V. Aladin 《Hydrobiologia》1995,307(1-3):85-97
Results of five expeditions to the Caspian Sea and 17 expeditions to the Aral Sea from 1976–1993 are presented. In these two large salt lakes, nine species of Podonidae were found, all of which were fairly euryhaline, except Caspievadne maximowitschi. Further, all of them were thermophilic, except Cornigerius bicornis, Caspievadne maximowitschi, and Pleopis polyphemoides. Sexual reproduction of the Podonidae in these two salt lakes appears to be insignificant. The possibility exists that parthenogenetic females of some species can live and reproduce even during the winter in the southern parts of the lakes. The complete disappearance of the Podonidae from the Aral Sea in 1989–1990 and the later reappearance of Podonevadne camptonyx in the north Aral in 1991, demonstrates that today it is possible to rehabilitate and conserve a small part of this lake.This paper is dedicated to the memory of David Frey, who gave the author the idea for this study, and discussed its main conclusions  相似文献   

15.
本文研究无花果蛋白酶(EC.3.4.4.12)在不同浓度盐酸胍溶液中分子构象与活力变化关系。酶的内源荧光光谱,圆二色光谱与酶活力的变化表明:荧光光谱呈现二个明显的变化区域,低浓度胍(低于2mol/L)中,荧光发射峰基本不变,但荧光强度随胍浓度上升,随胍浓度断续增大(高于2mol/L),酶的最大发射波长明显红移。当胍浓度低于1mol/L时,不仅不会使酶失活,反而使酶激活,当胍浓度高于1mol/L以上时,酶逐渐失活,使酶完全失活的胍浓度为6mol/L酶的圆二色光谱也随着胍浓度的改变而发生复杂的变化。将荧光变化,CD谱变化及活力改变结合起来,表明活力的激活与构象的明显变化似是同步发生的,从另一角度进一步说明酶活性部位柔性是充分表现酶活力所必需。  相似文献   

16.
本文旨在探明夏季不同昼夜温度模式对广聚萤叶甲发育及繁殖的影响。在实验室条件下,模拟了夏季常规的昼夜气温变化模式32℃±4℃、白天均温升高2℃及极端高温升高2℃,以恒温28℃为对照,研究上述温度模式对广聚萤叶甲的生长发育及繁殖动态的影响,并组建了广聚萤叶甲实验种群生命表。随日平均温度的增加,广聚萤叶甲卵的孵化率和幼虫存活率降低,发育历期缩短,成虫寿命及产卵量减少,但是对蛹的羽化率影响不大。白天均温升高2℃时,尽管广聚萤叶甲生殖力最低,但是其内禀增长率最高,种群加倍时间短。广聚萤叶甲能根据昼夜温度变化来改变生长发育特点以适应外环境界,通过缩短种群加倍时间来维持一定的种群数量。  相似文献   

17.
History of the montane forests of the northern Andes   总被引:2,自引:0,他引:2  
From the vascular plant genera of the tropical Andean montane forests about 65% have a tropical-neotropical, 15% tropical-Andean, 5% amphi-pacific (Malayo-American), 5% Austral-antarctic and 10% Holarctic distribution. The explosive evolution of Andean centred taxa probably started in the lower Tertiary from tropical Gondwana stock, when in the area of the present day Andes, locally there may have been hills up to 1 000m. With the final upheaval between the Late Miocene and Late Pliocene, extensive areas with a montane climate were created and populated from the low mountain flora by evolutionary radiation. Taxa of Austral-antarctic origin migrated along the Andean chain to the tropics. At the same time the formation of the Panama isthmus connected N. and S. America, and enabled many plants to enter the tropical Andes from the north. First to cross were tropical to subtropical and warm-temperate species from the Tertiary Laurasian flora that had migrated southward during the period of Miocene cooling, taking refuge in the montane tropics. Because the same happened in SE. Asia there is a good number of amphi-pacific taxa known as fossils from Tertiary Laurasia but largely extinct in the present-day Holarctic (e.g.,Trigonobalanus). Later to cross were cool-temperate to cold elements that still exist in the Holarctic (e.g.,Alnus andQuercus).  相似文献   

18.
The effect of methylmercury (MM) and MM plus sodium selenite (SE) on the activity of various GSH-dependent enzymes was studied in the liver and kidney of mice. Ten groups of mice were fed diets containing graded proportions of MM, alone or with graded quantities of SE. GST, GSH-Px, and GSSG-RED were assayed in the cytosolic fraction of liver and kidney homogenates. After treatment with MM, instead of the expected decrease in enzyme activities, an increase was observed in the kidney and a small decrease in the liver with no dose-response relation in either organ. In protected groups, a general pattern of induction was observed in both organs, but again there was little evidence of dose-response relationships. Detailed analysis of the results suggests that the effects observed were not directly caused by MM or SE but are the resultant of complex interactions presumably related to contemporaneous mechanisms of damage and repair.  相似文献   

19.
C-phycocyanin (CPC) and allophycocyanin (APC) were purified from Spirulina platensis, then the CPC was attached covalently to the APC by reacting their ∈-amino groups. The excitation energy could be transferred from the CPC to the APC in the CPC-APC conjugate. Intact phycobilisomes (PBS), consisting of CPC, APC, colourless linker polypeptides, and APC B or Lcm, were isolated from S. platensis. Spectroscopic properties of the isolated PBSs kept at 20 °C for various times showed that the connection between the APC and the APC B or Lcm was looser than that between the CPC and the APC in the isolated PBSs. The CPC-APC conjugate was more stable than the isolated PBSs, and the linker polypeptides had a minor influence on the excitation energy transfer characteristic between different phycobiliproteins in the PBS. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

20.
报道了缢蛏碱性磷酸酶(简称ALP)经不同浓度盐酸胍处理时酶的分子构象所发生的变化以及酶变化和失活的动力学过程。在胍中酶荧光发射峰强度下降,紫外差光谱在246nm和285nm处出现2个负峰,CD谱中酶的α螺旋度下降,且随浓度增大,变化程度也加大。动力学研究表明,酶在0.5mol/L、1.0mol/L、2.0mol/L3.0mol/L、4.0mol/L盐酸胍中的变性速度常数分别为3.21×10~(-4)s~(-1)、6.38×10~(-4)s~(-1)、2.17×10~(-3)s~(-1)、2.33×10~(-3)s~9-1)、5.17×10~(-3)s~(-1);而酶在相应盐酸胍中的失活速度常数分别为2.33×10~(-4)s~(-1)、3.57×10~(-4)s~(-1)、5.86×10~(-4)s~(-1)、1.14×10~(-3)s~(-1)、3.45×10~(-3)s~(-1);表现为失活与构象伸展变化基本平行。  相似文献   

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