单细胞动力学和变化在链形成藻 Chaetoceros affinisis 的链
Rickard Stenow1, Elizabeth K Robertson2, Martin J Whitehouse3
1Department of Marine Sciences, University of Gothenburg, Box 461, SE, 405 30, Gothenburg, Sweden. ristenow@gmail.com.
The ISME journal
|September 18, 2023
概括
植物浮游生物殖民地可以通过微生物园艺在营养稀缺的情况下生存. 二原子链将营养物转移到附着的细菌中,挑战现有的浮游生物营养流量模型.
科学领域:
- 海洋生物学 海洋生物学
- 微生物生态学 微生物生态学
- 生物地质化学生物地质化学
背景情况:
- 在营养物质有限的条件下,植物浮游生物的殖民地形成通常被视为有害.
- 了解细胞特异性营养吸收和这些殖民地内的微生物相互作用对于水生生态系统动态至关重要.
研究的目的:
- 在静止生长过程中研究细胞特异性营养同化和细菌相互作用的链形成藻 * Chaetoceros affinis * .
- 阐明殖民结构在营养循环和营养限制下的生存策略中的作用.
主要方法:
- 使用稳定的同位素标记物 (C-二碳酸盐,N-酸盐,N-) 来跟踪营养摄取.
- 采用二次离子质谱仪 (SIMS) 进行高分辨率,细胞特异的营养同化分析.
- 量化了对附着细菌的营养转移,并评估了它们的生长率.
主要成果:
- 早期的静止阶段在藻链中显示出均的营养同化.
- 附着的细菌在12小时内同化了高达5%的新固定碳和.
- 后来的静止阶段显示单个细胞的链长度减少和营养吸收增加;在同一链内观察到活跃和不活跃的细胞.
结论:
- 原子链可能采用"微生物园艺"策略,促进营养物质转移到相关细菌.
- 链内的短扩散距离支持营养交换,有助于细胞在N限制环境中的生存.
- 这种殖民战略挑战了人们对浮游生物群落中营养流动的传统理解.
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