【作者】 杨春香；

【导师】 林跃鑫； 林新坚；

【作者基本信息】 福建师范大学 ， 生物化学与分子生物学， 2004， 硕士

【摘要】 本文报道了镉对姬松茸菌丝生长、细胞结构和氨基酸组分等方面的影响，比较不同姬松茸菌株菌丝体的富镉特性，并利用氨基酸分析和RAPD分析初步探讨不同菌株富镉特性的分子机制。 不同姬松茸菌株接种在添加不同浓度镉的斜面培养基中生长，在(0～1mg／L)低镉浓度下，镉对菌丝的生长有一定的刺激作用，当镉浓度超过2mg／L时，菌丝生长受到明显的毒害作用。不同姬松茸菌株的菌丝生长受镉的影响程度明显不同，表明不同菌株对镉的耐受程度有明显差异。 在确立镉影响菌丝生长域值的基础上，以液体培养的方式探讨镉对菌丝体生长的影响。菌丝体镉含量测定结果表明，不同姬松茸菌株的富镉性存在明显差别，A28的富镉能力为A13的1.4～2.3倍：电镜观察证实，1mg／L的镉浓度即可对菌丝细胞产生毒害作用；氨基酸成分分析发现，富镉菌丝体内与镉结合蛋白紧密相关的胱氨酸含量显著减少。 对9个不同菌株的基因组进行RAPD扩增，并以平均连锁聚类分析法(Unweighted Pair Group Method Arithmetic Clustering，UPGMA)进行分析，结果表明：当遗传系数为0.87时，所有供试的菌株可分为四类，A13与A28分别属于第三类和第二类。 氨基酸含量的明显变化和RAPD分析结果提示，不同菌株的耐镉性和富镉性差异可能与其基因型有关。更多还原

【Abstract】 The effects of cadmium on the mycelia growth, amino acid content and the ability of accumulation cadmium in Agaricus blazei Murill were studied. The relationship between the genome of different strains and their accumulation cadmium properties also been discussed on molecular level.Different strains of Agaricus blazei were cultivated with linear concentration of cadmium culture media. The results showed that Cd could influence the mycelium growth of Agaricus blazei. At low concentration (0~ 1mg/L), Cd had stimulatory and poisonous effects on the mycelium growth. When Cd concentration was higher than 2mg/L, the mycelia appeared evidently phyto-toxicity symptoms. The sensitivity of the mycelium growth of different strains of Agaricus blazei to Cadmium was different.Base on the establishment of the certain concentration of cadmium that effected the mycelia growth, the different strains were cultivated with linear concentration of Cd by submerged fermentation. And the cadmium contents in mycelia were tested. The result showed that the strain A28 surpass A13 on the ability of accumulation cadmium. When Cd concentration was higher than 1mg/kg, the toxicity symptoms of mycelia were observed by scanning electron. The analysis of amino acid revealed that the cysteine was evidently reduceed in accumulation cadmium mycelia.The genome of different strains were further discussed by means of Random Amplified Polymophic DNA(RAPD). Unweighted Pair Group Method Arithmetic Clustering(UPGMA)were used to analysis the PCR electrophotogram which seven strains of Agaricus blazei genome amplified by 20 random primers. The results indicated that the tested strains can be dividedinto four classes when the similarity coefficient matrix is 0.87, A13 and A28which are quite difference in the accumulation of Cd are belonged to differentgroups.更多还原