Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, 85287-5701, USA.
State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
Appl Microbiol Biotechnol. 2019 Jun;103(12):5007-5014. doi: 10.1007/s00253-019-09817-9. Epub 2019 Apr 27.
During the culturing of cyanobacteria, heterotrophic bacteria can compete for nutrients, compromise the quality of the harvested biomass, or cause culture crashes. We systematically investigated the effects of depleting inorganic phosphate (Pi) on the growth of the cyanobacterium Synechocystis sp. PCC 6803, its community of heterotrophic bacteria, and the biomass's chemical composition. On the one hand, depleting Pi had minimal impact on total biomass, extracellular polymeric substances (ESP), soluble microbial products (SMP), and most types of intracellular organic polymers production. On the other hand, depleting Pi led to markedly less lipid content, less heterotrophic biomass, and a shift in the heterotrophic community from Burkholderiales to Sphingobacteriales and Saprospirales. The causes of the large impacts were that Synechocystis was much better at scavenging a very low Pi concentration and lowering the Pi available to the heterotrophs. This work lays a foundation for controlling the accumulation of heterotrophs and reducing their deleterious effects in cyanobacteria culturing.
在蓝细菌培养过程中，异养细菌会争夺营养物质，影响收获生物质的质量，甚至导致培养失败。我们系统地研究了耗尽无机磷 (Pi) 对蓝细菌集胞藻 PCC 6803 生长、其异养细菌群落和生物质化学组成的影响。一方面，耗尽 Pi 对总生物质、胞外聚合物 (ESP)、可溶性微生物产物 (SMP) 和大多数类型的细胞内有机聚合物的产生影响很小。另一方面，耗尽 Pi 导致脂质含量明显减少、异养生物质减少，异养群落从伯克霍尔德氏菌目转向鞘氨醇单胞菌目和螺旋体目。造成这种巨大影响的原因是集胞藻更善于从极低的 Pi 浓度中摄取 Pi，同时降低了异养生物可利用的 Pi 浓度。这项工作为控制异养生物的积累和减少它们在蓝细菌培养中的有害影响奠定了基础。
