裙带菜基因工程选择标记的研究

研究了裙带菜幼孢子体对10种选择试剂的敏感性。结果发现裙带菜幼孢子体对氯霉素、潮霉素敏感,对除草剂草丁膦极敏感(2天的LD50为8.57mg/L)。根据统计学的要求得出了这3种选择试剂对裙带菜幼孢子体的半致死剂量和95％可信限。本文的结果能为裙带菜基因工程选择标记的建立提供依据。

β-半乳糖苷酶基因(lacZ)在大型经济海藻裙带菜中的瞬间表达

用高压氦气式基因枪将SV4 0启动子驱动下的 β 半乳糖苷酶基因 (lacZ)导入大型经济海藻裙带菜不同部位的组织切块中 ,4 8小时后染色检测 ,在假根、孢子叶和叶片中均检测到了lacZ的瞬间表达。研究还发现 ,对于裙带菜组织块的基因枪法转化 ,压强130 0psi优于 110 0psi。另外在裙带菜中没有发现半乳糖苷酶的染色本底。本文结果提示 :基因枪法是有效的裙带菜遗传转化方法 ;lacZ可以作为裙带菜基因工程研究的报告基因 ,SV4 0启动子能有效驱动外源基因在裙带菜中表达 ,没有组织特异性。这是lacZ在裙带菜中表达的首次报道 。

β-半乳糖苷酶基因(lacZ)在海藻裙带菜中的稳定表达

借鉴海带遗传转化模式 ,利用基因枪法将 β 半乳糖苷酶基因 (lacZ)导入裙带菜雄配子体中 ,一部分诱导形成营养增殖的丝状体 ,另一部分和雌配子体受精生成孢子体。五个月后组织化学染色结果表明 5 %的孢子体个体和 30 %的丝状体细胞表现了lacZ的稳定表达 ,利用PCR和PCR Southern检测得到了预期的阳性信号。本文结果提示了利用基因枪转化方法 。

EFFECT OF LIGHT INTENSITY ON THE TOTAL LIPID AND FATTY ACID COMPOSITION OF SIX STRAINS OF MARINE DIATOMS

The effect of light intensity (1500 lx and 5000 lx) on the total lipid and fatty acid composition of six strains of marine diatoms Cylindrotheca fusiformis (B211), Phaeodactylum tricornutum (B114, B118 and B221) Nitzschia closterium (B222) and Chaetoceros gracilis (B13) was investigated. The total lipids of B13, B114, and B211 grown at 5000 lx were lower than those grown at 1500 lx. No evident changes were observed in B118, B221 and B222. Fatty acid composition changed considerably at different light intensity although no consistent correlation between the relative proportion of a single FA and light intensity. The major fatty acids of the 6 strains were 14:0, 16:0, 16:1(n-7) and 20:5(n-3). Cylindrotheca fusiformis had high percentage of 20:4n-6 (9.2-10.9%). The total polyunsaturated fatty acid in all 6 strains decreased with increasing light intensity. The percentage of the highly unsaturated fatty acid eicosapentaenoic acid (EPA) decreased with increasing light intensity in all strains except Chaetoceros gracilis.