Carbon-ion irradiation is a technique for trait improvement in the microalgae,but the underlying mechanisms that how it altered the biomass,and photosynthetic pigments accumulation were unclear.One mutant(DS240G-1)was...Carbon-ion irradiation is a technique for trait improvement in the microalgae,but the underlying mechanisms that how it altered the biomass,and photosynthetic pigments accumulation were unclear.One mutant(DS240G-1)was obtained from Dunaliella salina by heavy ion irradiation mutagenesis.Compared to the wild type,the biomass accumulation and maximum growth rate of DS240G-1 were increased by 34%and 55%respectively,and itsβ-carotene content was 21%higher than the wild type.Subsequent analysis of the chlorophyll fluorescence parameters indicated that higherβ-carotene productivity was likely owing to the improved maximum quantum efficiency(Fv/Fm)and decreased thermal dissipation of photosynthesis in DS240G-1 than that of wild type during cultivation.In addition,the result of this study revealed that high content of ROS may induceβ-carotene accumulation in mutant DS240G-1.Also,the total fatty acid(TFA)content in mutant DS240G-1 was 79%higher than that in wild type.Owing to its highβ-carotene productivity and total fatty acid content,DS240G-1 could be considered as a promising candidate for microalgaeβ-carotene and biodiesel production.This work provided the first insight into the biological effects involved in carbon-ions irradiation on the photosynthetic activity of D.salina.展开更多
Using Rapid Amplification of cDNA ends (RACE) technique, the full-length cDNA en-coding a NaCl-induced fructose-1, 6- diphosphate aldolase (DsALDP) was obtained. It was shown that the DsALDP had a relatively high homo...Using Rapid Amplification of cDNA ends (RACE) technique, the full-length cDNA en-coding a NaCl-induced fructose-1, 6- diphosphate aldolase (DsALDP) was obtained. It was shown that the DsALDP had a relatively high homology (66%—73%) to chloroplast fructose-1, 6-diphos- phate aldolase (AldP) in many plants according to their amino acid sequences. The phylogenetic analysis further confirmed that AldP in alga is the nearest to DsALDP. As to its expression pattern, DsALDP was de novo synthesized by NaCl induction. Its expression level was significantly changed with inducing time. After the selected DsALDP cDNA subcloned into a binary vector pBI121, the new construct was introduced into tobacco by Agrobacterium tumefaciens. The results of Southern blot and RT-PCR analysis of four transgenic T1 plants indicated that DsALDP was integrated into genome of these transgenic plants and effectively expressed. Aldolase activities have been detected in T1-1, T1-2 and T1-3 plants by bioassay under 100—200 mmol/L NaCl. It was also observed that proline contents in them were differentially increased.展开更多
基金This work was supported by the National Nature Science Foundation of China(Grant No.11665011)Gansu Provincial Science and Technology Program(Grant No.18JR2JG001).
文摘Carbon-ion irradiation is a technique for trait improvement in the microalgae,but the underlying mechanisms that how it altered the biomass,and photosynthetic pigments accumulation were unclear.One mutant(DS240G-1)was obtained from Dunaliella salina by heavy ion irradiation mutagenesis.Compared to the wild type,the biomass accumulation and maximum growth rate of DS240G-1 were increased by 34%and 55%respectively,and itsβ-carotene content was 21%higher than the wild type.Subsequent analysis of the chlorophyll fluorescence parameters indicated that higherβ-carotene productivity was likely owing to the improved maximum quantum efficiency(Fv/Fm)and decreased thermal dissipation of photosynthesis in DS240G-1 than that of wild type during cultivation.In addition,the result of this study revealed that high content of ROS may induceβ-carotene accumulation in mutant DS240G-1.Also,the total fatty acid(TFA)content in mutant DS240G-1 was 79%higher than that in wild type.Owing to its highβ-carotene productivity and total fatty acid content,DS240G-1 could be considered as a promising candidate for microalgaeβ-carotene and biodiesel production.This work provided the first insight into the biological effects involved in carbon-ions irradiation on the photosynthetic activity of D.salina.
文摘Using Rapid Amplification of cDNA ends (RACE) technique, the full-length cDNA en-coding a NaCl-induced fructose-1, 6- diphosphate aldolase (DsALDP) was obtained. It was shown that the DsALDP had a relatively high homology (66%—73%) to chloroplast fructose-1, 6-diphos- phate aldolase (AldP) in many plants according to their amino acid sequences. The phylogenetic analysis further confirmed that AldP in alga is the nearest to DsALDP. As to its expression pattern, DsALDP was de novo synthesized by NaCl induction. Its expression level was significantly changed with inducing time. After the selected DsALDP cDNA subcloned into a binary vector pBI121, the new construct was introduced into tobacco by Agrobacterium tumefaciens. The results of Southern blot and RT-PCR analysis of four transgenic T1 plants indicated that DsALDP was integrated into genome of these transgenic plants and effectively expressed. Aldolase activities have been detected in T1-1, T1-2 and T1-3 plants by bioassay under 100—200 mmol/L NaCl. It was also observed that proline contents in them were differentially increased.
