Fisher Carolyn L, Fong Michelle V, Lane Pamela D, Carlson Skylar, Lane Todd W
Physical and Life Science Directorate, Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
Department of Chemistry, University of the Pacific, Stockton, CA 95211, USA.
Microorganisms. 2023 Mar 18;11(3):786. doi: 10.3390/microorganisms11030786.
Loss of algal production from the crashes of algal mass cultivation systems represents a significant barrier to the economic production of microalgal-based biofuels. Current strategies for crash prevention can be too costly to apply broadly as prophylaxis. Bacteria are ubiquitous in microalgal mass production cultures, however few studies investigate their role and possible significance in this particular environment. Previously, we demonstrated the success of selected protective bacterial communities to save cultures from grazing by the rotifer . In the current study, these protective bacterial communities were further characterized by fractionation into rotifer-associated, algal-associated, and free-floating bacterial fractions. Small subunit ribosomal RNA amplicon sequencing was used to identify the bacterial genera present in each of the fractions. Here, we show that , , and in algae and rotifer fractions from rotifer-infected cultures likely play key roles in protecting algae from rotifers. Several other identified taxa likely play lesser roles in protective capability. The identification of bacterial community members demonstrating protective qualities will allow for the rational design of microbial communities grown in stable co-cultures with algal production strains in mass cultivation systems. Such a system would reduce the frequency of culture crashes and represent an essentially zero-cost form of algal crop protection.
藻类大规模培养系统崩溃导致藻类产量损失，这是基于微藻的生物燃料经济生产的重大障碍。目前预防崩溃的策略作为预防措施广泛应用成本过高。细菌在微藻大规模生产培养中普遍存在，然而很少有研究调查它们在这个特定环境中的作用和可能的重要性。此前，我们证明了选定的保护性细菌群落能够成功保护培养物免受轮虫的捕食。在当前研究中，这些保护性细菌群落通过分离为与轮虫相关、与藻类相关和自由漂浮的细菌部分进行了进一步表征。利用小亚基核糖体RNA扩增子测序来鉴定每个部分中存在的细菌属。在这里，我们表明，来自受轮虫感染培养物的藻类和轮虫部分中的 、 和 可能在保护藻类免受轮虫侵害方面发挥关键作用。其他几个已鉴定的分类群在保护能力方面可能发挥较小的作用。鉴定出具有保护特性的细菌群落成员将有助于合理设计在大规模培养系统中与藻类生产菌株稳定共培养的微生物群落。这样的系统将减少培养物崩溃的频率，并代表一种基本零成本的藻类作物保护形式。
