ACTA Scientiarum Naturalium Universitatis Pekinensis
Effects of Different Light Qualities on the Growth of Thermophilic Cyanobacteria sp.
LI Kai, GONG Yiwei, LI Xingkang, ZHANG Yanting, Maurycy Daroch, JIN Peng†
School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055; † Corresponding author, E-mail: jinpeng@pkusz.edu.cn
Abstract In order to understand the lighting quality effects on the light-adaptive growth of cyanobacteria which does not express phycoerythrin, the thermophilic cyanobacteria PCC6715 in logarithmic growth phase was cultured by using white light (control), red light, and blue light with photosynthetically effective photon quantum density (PAR) of 100 μmol/(m2·s). Compared with the growth characteristics of PCC6715 under white light conditions, the changes in the measured and analyzed values of PCC6715 under other light qualities were as follows: the dry weight of PCC6715 significantly increased under blue light and significantly reduced under red light; the red and blue light have different effects on the start time and duration of the photosynthetic pigment synthesis of PCC6715; the maximum light energy conversion efficiency (Fv/fm) of PCC6715 significantly increased under blue light and decreased significantly under red light; after 6 days of culture, the Fv/fm of PCC6715 under red and blue light conditions tends to stable. In conclusion, the blue spectrum lighting promotes the growth of PCC6715, while red light inhibits the growth of PCC6715. At the same time, PCC6715 produces light-adaptive growth under both red and blue light, the reduction of phycocyanin content caused light-adaptive growth of PCC6715 in red light, and the light-adaptive growth of PCC6715 in blue light was due to the increase of phycocyanin content. Key words cyanobacteria; thermophilic cyanobacteria; light quality; light-adaptive growth; phycocyanin
嗜热蓝细菌分离于45ºc以上的温泉地带, 是2000余种蓝细菌的重要组成菌种[1–2]。蓝细菌不仅对水体生态系统的维持有重要作用, 而且遗传学研
究发现, 嗜热蓝细菌的存在是地球上能够出现其他生命体的重要原因[3–6]。蓝细菌是地球上重要的初级生产力, 环境中的光质和光强对其合成有机物的
1.3
Fig. 1
Culture light quality conditions of
干重测定
黑暗处静置1小时, 然后使用叶绿素荧光仪 在10 μmol/(m2·s)的 620 nm波段的红光条件下测得PCC6715 光合系统的初始荧光 F0, 在 210 μmol/ (m2·s)的 620 nm 波段的红光条件下测得PCC6715光合系统的最大荧光Fm, 最大光能利用效率的测定公式为
Fv=fm− F0, Qy= Fv/ Fm 。
(3) (4)
本研究使用 Excel 2010计算实验数据, 使用Graphpad Prism 5.0软件进行单因素方差分析(Oneway ANOVA)。
2 结果与分析2.1 不同光质对嗜热蓝细菌影响
在不同光质的培养过程中, 对照组与实验组中PCC6715的干重均呈增加的趋势(图2)。与对照组白光相比, PCC6715的干重在蓝光下较高, 红光下较低。相对于白光, 蓝光对PCC6715的生长有显著的
Fig. 2
Difference in dry weight of light quality cultures
促进作用, 红光不利于对数生长期PCC6715的生长。
2.2 不同光质对嗜热蓝细菌色素及 的影响的光合
PCC6715的光合色素含量在不同光质中均呈现上升趋势, 最大光能转化效率均呈现先增加、后趋于稳定的趋势。PCC6715叶绿素a含量的变化如图3(a)所示, 与白光对照组相比, PCC6715在蓝光培养
北京大学学报(自然科学版) a
Fig. 5
Characteristics of light adaptability of
merolae. 35–46 Pedersen D, Miller S R. Photosynthetic temperature adaptation during niche diversification of the thermophilic cyanobacterium Synechococcus A/B clade. ISME Journal, 2016, 11(4): 1053–1057 Maccoll R. Cyanobacterial phycobilisomes. Journal of Structural Biology, 1998, 124(2/3): 311–334 Edwards M R, Gantt E. Phycobilisomes of the thermophilic blue-green alga Synechococcus lividus. Journal of Cell Biology, 1971, 50(3): 896–900 Bennett A, Bogorad L. Complementary chromatic adaptation in a filamentous blue-green alga. Journal of Cell Biology, 1973, 58(2): 419–435王燕, 张亚见, 何茂盛, 等. 光质对植物形态结构和生长的影响. 安徽农业科学, 2018, 46(19): 22–25王肖肖. 藻类光合作用捕光色素蛋白复合物—藻胆体的结构、性质及功能研究[D]. 曲阜: 曲阜师范大学, 2018韩丽丽. 浅水水体浮游藻类光合活性研究[D].汉: 华中科技大学, 2013刘洪艳, 潘伶俐, 施定基. 不同光质对紫球藻生长及藻胆素含量的影响. 天津科技大学学报, 2007, 22(1): 26–28韩军军. 光质对坛紫菜生长和生理学特性的影响及坛紫菜丝状体蓝光效应的转录组分析[D]. 上海: 上海海洋大学, 2017 Kehoe D M. Chromatic adaptation and the evolution of light color sensing in cyanobacteria. Proc Natl Acad Sci USA, 2010, 107(20): 9029–9030 Zhao Longsheng, Li Kang, Wang Qianmin, et al. Nitrogen Starvation Impacts the Photosynthetic Performance of Porphyridium cruentum as Revealed by Chlorophyll a Fluorescence. Sci Rep, 2017, 7(1): 8542韩军军, 钟晨辉, 何培民, 等. 不同光质 LED 光源对坛紫菜自由丝状体生长和生理特性的影响. 水产学报, 2017, 41(2): 230–239 Palenik B. Chromatic adaptation in marine Synechococcus strains. Applied & Environmental Microbiology, 2001, 67(2): 991–994王肖肖, 秦松, 杨革, 等. 藻胆体的结构与能量传递功能. 海洋科学, 2017, 41(12): 139–145
Plant Physiology, 2017, 174(1):
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