来自蓝藻细菌内生体的基因异质表达突出显示了与其藻宿主之间的基质交换
Mercedes Nieves-Morión1,2, Sergio Camargo2, Sepehr Bardi1
1Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm SE-106 91, Sweden.
PNAS nexus
|June 29, 2023
概括
藻-蓝藻共生依赖于藻宿主提供有机碳,以推动蓝藻共生体Richelia euintracellularis的固.
科学领域:
- 海洋微生物学 海洋微生物学
- 共生关系是共生关系.
- 生物地质化学循环是什么
背景情况:
- 像Hemiaulus hauckii这样的藻与低营养海洋中的 (N2) 固定蓝藻菌有关.
- 内生生物Richelia euintracellularis生活在H. hauckii细胞内,但它们的相互作用机制尚不清楚.
研究的目的:
- 研究Hemiaulus hauckii-Richelia euintracellularis共生中的生理相互作用和营养交换.
- 确定涉及从藻宿主转移营养物质到蓝藻共生体的特定分子和途径.
主要方法:
- 在模型生物中R.euintracellularis蛋白质的异质基因表达 (大肠杆菌,蓝藻细菌突变).
- 对ABC载体中一个中性逆转酶和溶解物结合蛋白 (SBPs) 的生物化学表征.
- 野生藻种群中关键基因的转录分析.
主要成果:
- 在R.euintracellularis中鉴定出一种中性逆转酶,可以将糖糖代谢成葡萄糖和果糖.
- 描述了SBP,揭示了宿主衍生的糖,氨基酸和精子素作为支共生体的基质.
- 在野生H. hauckii中检测到逆转酶和SBP的转录,证实了现场相关性.
结论:
- 藻宿主提供必需的有机碳化合物,以推动内共生R.euintracellularis的N2固定.
- 这种营养交换对于这个全球重要的海洋共生体的生存和功能至关重要.
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