BDSF抑制白色念珠菌菌丝生长
发布时间：2018-10-15 10:12
【摘要】：白色念珠菌(Candida albicans),又称白色假丝酵母(以下简称白念),是人体一种极其重要的条件致病真菌。在正常人体中,白念是一种无害的共生真菌,其广泛地定植于人体的各种生态位,其中包括健康人体的口腔、胃肠道、阴道和皮肤。但是,在免疫力低下的人群中,如乙肝病人、艾滋病人以及长期罹患糖尿病的病人,白念可引起感染甚至念珠菌病,轻者可导致表面黏膜感染、重者可发展为系统疾病危及生命。在众多致病因素当中,形态转变即从酵母形态转变为菌丝形态,是极其重要的因素之一。 BDSF是一种小分子钻链脂肪酸,来自Burkholderia cenocepacia。在结构上,BDSF与DSF (diffusibe signal factor)十分相似,而DSF是由来自Xanthomonas campestris的RpfF酶合成。基因Bcam0581编码RpfF酶的同源物,对于BDSF的合成是必需的。该基因在Burkholderia cenocepacia中高度保守且广泛分布。外源添加BDSF,可使DSF缺陷的Xanthomonas campestris的生物膜和胞外多糖表型得以恢复。 本论文实验可分为两部分。第一部分,首先以白念的酵母相为起点,对BDSF抑制白念菌丝的生长进行了验证；第二部分,以白念的菌丝相为起点,检测BDSF是否能促进白念的菌丝相向酵母相转变。实验过程中,我们选择GS培养基作为菌丝诱导培养基。GS培养基具有较好的诱导白色念珠菌的酵母态向菌丝态转化的能力,白色念珠菌在该培养基中三小时菌丝形成率高达90%以上,四小时菌丝形成率高达95%以上。 实验表明,以白念的酵母态为起点,当浓度≥30μM时BDSF具有强烈地抑制白念菌丝生长的能力。对于已经形成的菌丝,在30μM和60μM时,BDSF并不抑制菌丝进一步生长和分支,但随着菌丝的生长,新生的菌丝则不断地转变为酵母态,尽管早期生成的少量的菌丝并未转变为酵母态；当BDSF浓度增加至120μM时,BDSF几乎完全抑制了菌丝生长和分支。
[Abstract]:Candida albicans (Candida albicans), also known as Candida albicans, is an extremely important conditional pathogenic fungus. In the normal human body, Bai Nian is a harmless symbiotic fungus, which is widely located in various ecological sites of the human body, including the oral cavity, gastrointestinal tract, vagina and skin of the healthy human body. However, in people with low immunity, such as hepatitis B patients, AIDS patients and patients with chronic diabetes, candida albicans can cause infections and even candidiasis, and mild cases can lead to superficial mucosal infections. Serious diseases can develop into systemic diseases that are life-threatening. Among the many pathogenic factors, morphological transformation from yeast to hyphae is one of the most important factors. BDSF is a small molecular fatty acid from Burkholderia cenocepacia.. The structure of BDSF is similar to that of DSF (diffusibe signal factor), and DSF is synthesized by RpfF enzyme from Xanthomonas campestris. The gene Bcam0581 encodes the congeners of RpfF enzymes, which are necessary for the synthesis of BDSF. The gene is highly conserved and widely distributed in Burkholderia cenocepacia. Exogenous addition of BDSF, could restore the biofilm and extracellular polysaccharide phenotype of DSF deficient Xanthomonas campestris. The experiment can be divided into two parts. In the first part, the inhibitory effect of BDSF on the growth of the mycelium was verified by using the yeast phase as the starting point, and in the second part, the effect of BDSF on the transformation of the hyphae from the white to the yeast was examined. During the experiment, we chose GS medium as the hyphal induction medium. GS medium had better ability of inducing Candida albicans yeast to hyphae transformation. The mycelium formation rate of Candida albicans was above 90% in three hours and 95% in four hours. The results showed that BDSF had strong ability to inhibit mycelium growth when the concentration was more than 30 渭 M. For the formed hyphae, at 30 渭 M and 60 渭 M, BDSF did not inhibit the further growth and branching of the mycelium, but with the growth of the hyphae, the new hyphae changed to yeast state continuously, although a small amount of hyphae produced in the early stage did not change to yeast state. When the concentration of BDSF increased to 120 渭 M, BDSF almost completely inhibited the mycelium growth and branching.
【学位授予单位】：复旦大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：R379.4
本文编号：2272216
[Abstract]:Candida albicans (Candida albicans), also known as Candida albicans, is an extremely important conditional pathogenic fungus. In the normal human body, Bai Nian is a harmless symbiotic fungus, which is widely located in various ecological sites of the human body, including the oral cavity, gastrointestinal tract, vagina and skin of the healthy human body. However, in people with low immunity, such as hepatitis B patients, AIDS patients and patients with chronic diabetes, candida albicans can cause infections and even candidiasis, and mild cases can lead to superficial mucosal infections. Serious diseases can develop into systemic diseases that are life-threatening. Among the many pathogenic factors, morphological transformation from yeast to hyphae is one of the most important factors. BDSF is a small molecular fatty acid from Burkholderia cenocepacia.. The structure of BDSF is similar to that of DSF (diffusibe signal factor), and DSF is synthesized by RpfF enzyme from Xanthomonas campestris. The gene Bcam0581 encodes the congeners of RpfF enzymes, which are necessary for the synthesis of BDSF. The gene is highly conserved and widely distributed in Burkholderia cenocepacia. Exogenous addition of BDSF, could restore the biofilm and extracellular polysaccharide phenotype of DSF deficient Xanthomonas campestris. The experiment can be divided into two parts. In the first part, the inhibitory effect of BDSF on the growth of the mycelium was verified by using the yeast phase as the starting point, and in the second part, the effect of BDSF on the transformation of the hyphae from the white to the yeast was examined. During the experiment, we chose GS medium as the hyphal induction medium. GS medium had better ability of inducing Candida albicans yeast to hyphae transformation. The mycelium formation rate of Candida albicans was above 90% in three hours and 95% in four hours. The results showed that BDSF had strong ability to inhibit mycelium growth when the concentration was more than 30 渭 M. For the formed hyphae, at 30 渭 M and 60 渭 M, BDSF did not inhibit the further growth and branching of the mycelium, but with the growth of the hyphae, the new hyphae changed to yeast state continuously, although a small amount of hyphae produced in the early stage did not change to yeast state. When the concentration of BDSF increased to 120 渭 M, BDSF almost completely inhibited the mycelium growth and branching.
【学位授予单位】：复旦大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：R379.4
【参考文献】
相关期刊论文 前1条
1 陈静,陈江野;CEK2和CSK1基因的敲除对白色念珠菌形态的影响[J];实验生物学报;2001年01期
，本文编号：2272216
本文链接：https://www.wllwen.com/xiyixuelunwen/2272216.html
最近更新
教材专著
