脂肪酸对纽莫康定B0生物合成的影响

脂肪酸对纽莫康定B0生物合成的影响(任务书,论文9000字)
摘 要
纽莫康定B0是由丝状真菌Glarea lozoyensis发酵产生的脂肽,是抗真菌药物卡泊芬净的前体。该酯肽由六肽环和脂肪酸链组成,其脂肪酸链和六肽环分别通过聚酮合酶和非核糖体肽合成酶合成。外源脂肪酸对纽莫康定B0的合成有着重要作用:一方面它可以作为碳源参与到TCA循环中,另一方面可以为纽莫康定B0的合成提供乙酰辅CoA等聚酮合成前体,显著提高其产量。因此,本文考察了添加不同的外源脂肪酸对G. lozonolysis发酵的影响。
本文以G. lozonolysis菌株为材料,首先考察了豆油和豆油中主要成分油酸(油酸甲酯)、棕榈酸(棕榈酸甲酯)、硬脂酸(单硬脂酸甘油酯)、亚油酸三种脂肪酸对G. lozonolysis发酵生产纽莫康定B0的影响。结果表明:棕榈酸、硬脂酸、亚油酸及豆油都促进了纽莫康定B0的生产。其中棕榈酸甲酯0.5 g/L的促进作用最明显,当棕榈酸甲酯添加至终浓度为0.5 g/L时,纽莫康定B0产量最高,产量达到最大值963.1 mg/L,相比对照组的产量增长了45.34 %。
微生物利用油脂的过程是先将长链油脂降解成脂肪酸和甘油,长链脂肪酸进而被降解成短链脂肪酸。通过对比较油酸钠、油酸甲酯、甘油和乙酸钠对G. lozonolysis发酵生产纽莫康定B0的影响,发现他们对发酵产量的影响由高到低排序为乙酸钠>油酸钠>油酸甲酯>对照>甘油。结果表明:盐比油脂好;短链脂肪酸比长链脂肪酸好;甘油对发酵起抑制作用。当乙酸钠添加至终浓度为0.1 g/L时,产量提高最多,产值为1268 mg/L,相比对照提高了91.5 %。
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关键词:Glarea lozoyensis 纽莫康定B0 外源脂肪酸
The effect of fatty acid on Pneumocandin B0 biosynthesis
ABSTRACT
Glarea lozoyensis is a production strain of Pneumocandin B0 , which is an antifungal-active lipopeptide that can cause damage to the fungal cell wall , but not on the human body . Pneumocandin B0 is an ester peptide consisting of hexapeptide loops and fatty acids , and its fatty acid and hexapeptide loops are synthesized by polyketone synthase and non-ribose peptide synthetase . Exogenous fatty acids play an important role in the synthesis of Pneumocandin B0 : on the one hand , it can be used as a carbon source to participate in the TCA cycle ; on the other hand , it can provide polyketone synthesis precursors such as acetylene coA for the synthesis of Pneumocandin B0 , significantly increase its production . Therefore , this paper investigated the effect of adding different exogenous fatty acids on the fermentation of G. lozoyensis .
In this paper , G. lozonolysis was used as the material , and it investigated the effects of soybean oil , oleic acid (sodium oleate) , palmitic acid (methyl palmitate) , stearic acid (glyceryl monostearate) and linoleic acid on fermentation . The results showed that methyl palmitate had the most better effect on the production of Pneumocandin B0 , and when the final concentration was 0.5 g/L by adding soybean oil , the yield of Pneumocandin B0 reached the highest value of 963.1 mg/L , and the output with an increase of 45.34 % . [资料来源:http://www.doc163.com]
Finally , the results showed that the salt was better than the oil ; the glycerin had the inhibitory effect on the fermentation . The best condition of improve Pneumocandin B0 fermentation yield was 0.1 g/L sodium acetate , the output value was 1268 mg/L , which was 91.5 % higher than the control .
Keywords: Glarea lozoyensis; Pneumocandin B0;Exogenous fatty acid


目 录
摘 要 I
ABSTRACT II
第一章 文献综述 1
1.1 棘白菌素类抗生素 1
1.2 纽莫康定B0合成机制 1
1.2.1 纽莫康定B0的结构 1
1.2.2 主链的合成 3
1.3 前体添加对PKS途径的影响 4
1.4 前体添加对NRPS途径的影响 5 [来源:http://www.doc163.com]
1.5 研究意义 6
第二章 实验材料 7
2.1 菌株来源 7
2.2 实验器材 7
2.3 实验试剂 8
第三章 实验方法 9
3.1 发酵方法 9
3.1.1 培养基配方 9
3.2 培养方式 9
3.3 实验方法 9
3.3.1 纽莫康定B0标准曲线制备 9
3.3.2 葡萄糖、果糖、甘露醇标准曲线制备 9
3.3.3 测纽莫康定B0发酵液中纽莫康定B0含量 10
3.3.4 发酵液中残余糖类含量测定 10
3.3.5 生物干重测定 10
第四章 实验结果与讨论 11
4.1 标准曲线测定结果 11
4.1.1 纽莫康定B0标准曲线制备结果 11
4.1.2 葡萄糖、果糖、甘露醇曲线制备结果 11 [来源:http://Doc163.com]
4.2 豆油及豆油主要成分对纽莫康定B0发酵产量的影响。 12
4.2.1 豆油的主要成分 12
4.2.2 豆油及豆油主要成分对纽莫康定B0的影响 13
4.3 前体添加对纽莫康定B0发酵产量的影响 14
4.3.1 脂肪酸两种形式对纽莫康定B0的影响 14
结语 16
5.1 结论 16
5.2 展望 16
参考文献 17
致谢 20 [版权所有:http://DOC163.com]
