Specific Photosynthetic Rate Enhancement by Cyanobacteria Coated Onto Paper Enables Engineering of Highly Reactive Cellular Biocomposite "Leaves"
Specific Photosynthetic Rate Enhancement by Cyanobacteria Coated Onto Paper Enables Engineering of Highly Reactive Cellular Biocomposite "Leaves"
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DOI：
10.1002/bit.25280
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发表时间：
2014-10-01
影响因子：
3.8
通讯作者：
Flickinger, Michael C.
中科院分区：
文献类型：
--
作者：
Bernal, Oscar I.;Mooney, Charles B.;Flickinger, Michael C.
我们描述了一种乳胶湿聚结挤出涂布法，产生高达10倍的特定光合速率增强硝酸盐限制的非生长蓝藻沉积到纸上，水合和放置在气相中的小管光生物反应器。这些植物叶片状的生物复合材料被用来研究蓝细菌菌株的耐光照和温度使用太阳模拟器。我们报告持续的CO2吸收和O-2生产500小时的水合气相纸涂层的非生长聚球藻PCC 7002，集胞藻PCC 6803，集胞藻PCC 6308，鱼腥藻PCC 7120。通过胶乳粘合剂固定在纸表面上的硝酸盐饥饿的蓝细菌没有从涂层中生长到本体液体中。在聚球藻涂层中的平均CO2消耗速率为5.67 mmol m（-2）h（-1），这与文献中报道的在类似实验条件下拟南芥叶片的速率（18 mmol m（-2）h（-1））非常接近。我们观察到氧气产生与二氧化碳消耗的平均比率（光合商，PQ）在1.3和1.4之间，这可能表明生长过程中对硝酸盐同化的强烈依赖，并用于开发用于内在动力学研究的非生长培养基配方。在由浓缩100- 300倍的湿细胞团制备的蓝细菌生物复合材料中的光合作用增强因子（PIF）（由乳胶涂层中的硝酸盐限制的蓝细菌产生的O-2/由硝酸盐限制的细胞悬浮液产生的O-2）与在相同的硝酸盐限制的非生长条件下的悬浮液中的细胞相比显示出高7-10倍的特异性反应性。这是第一次报告的变化蓝细菌的耐受性的温度和光强度沉积后，作为一个薄的涂层上的多孔基质，这具有重要意义的气相光生物反应器设计使用多孔复合材料。冷冻断裂SEM和共聚焦显微镜图像上的纸生物复合材料的细胞涂层分布表明，在涂层中的细胞的空间排列可以影响光反应性。这种技术可用于在气相中的柔性微流体装置上制造非常稳定的多生物体复合涂层，能够在更宽的波长范围内收集光，以优化耐热，耐干燥或耐盐的蓝藻，这些蓝藻产生O-2并分泌由CO2合成的液体燃料前体。(C)2014 Wiley Periodicals，Inc.
We describe a latex wet coalescence extrusive coating method that produces up to 10-fold specific photosynthetic rate enhancements by nitrate-limited non-growing cyanobacteria deposited onto paper, hydrated and placed in the gas-phase of small tube photobioreactors. These plant leaf-like biocomposites were used to study the tolerance of cyanobacteria strains to illumination and temperature using a solar simulator. We report sustained CO2 absorption and O-2 production for 500 h by hydrated gas-phase paper coatings of non-growing Synechococcus PCC7002, Synechocystis PCC6803, Synechocystis PCC6308, and Anabaena PCC7120. Nitrate-starved cyanobacteria immobilized on the paper surface by the latex binder did not grow out of the coatings into the bulk liquid. The average CO2 consumption rate in Synechococcus coatings is 5.67 mmol m(-2) h(-1) which is remarkably close to the rate reported in the literature for Arabidopsis thaliana leaves under similar experimental conditions (18 mmol m(-2) h(-1)). We observed average ratios of oxygen production to carbon dioxide consumption (photosynthetic quotient, PQ) between 1.3 and 1.4, which may indicate a strong dependence on nitrate assimilation during growth and was used to develop a non-growth media formulation for intrinsic kinetics studies. Photosynthetic intensification factors (PIF) (O-2 production by nitrate-limited cyanobacteria in latex coatings/O-2 produced by nitrate-limited cell suspensions) in cyanobacteria biocomposites prepared from wet cell pellets concentrated 100- to 300-fold show 7-10 times higher specific reactivity compared to cells in suspension under identical nitrate-limited non-growth conditions. This is the first report of changes of cyanobacteria tolerance to temperature and light intensities after deposition as a thin coating on a porous matrix, which has important implications for gas-phase photobioreactor design using porous composite materials. Cryo-fracture SEM and confocal microscopy images of cell coating distribution on the paper biocomposite suggest that the spatial arrangement of the cells in the coating can affect photoreactivity. This technique could be used to fabricate very stable, multi-organism composite coatings on flexible microfluidic devices in the gas-phase capable of harvesting light in a broader range of wavelengths, to optimize thermotolerant, desiccation tolerant, or halotolerant cyanobacteria that produce O-2 with secretion of liquid-fuel precursors synthesized from CO2. (C) 2014 Wiley Periodicals, Inc.