FlowRACS法により低存在量の海洋炭素固定細菌の発見を高速化（FlowRACS-Based Method Speeds Discovery of Low-Abundance Marine Carbon-Fixing Bacteria）

2026-09-29 中国科学院（CAS）

FlowRACS-based workflow for mining low-abundance functional marine microorganisms (Image by QIBEBT)

＜関連情報＞

• https://english.cas.cn/newsroom/research-news/202609/t20260929_1201569.shtml
• https://www.sciencedirect.com/science/article/abs/pii/S0960852426018572

フローモードラマン活性化細胞選別法による海洋性CO2固定細菌の機能スクリーニングおよび単細胞培養 Functional screening and single-cell cultivation of marine CO2-fixing bacteria via flow-mode Raman-activated cell sorting

Dong Cheng, Zhiguang Xu, Yishang Ren, Huihui Pan, Guangxia Ma, Zongze Shao, Emma Rocke, Xiaoyan Jing, Jian Xu
Bioresource Technology
Available online 9 September 2026
DOI:https://doi.org/10.1016/j.biortech.2026.135775

Highlights

• scRACS-Culture isolates active marine CO₂-fixing bacteria within 7 days.
• Paraburkholderia aromaticivorans FR-4 couples nitrite oxidation with CO₂ fixation.
• Strain FR-4 exhibits flexible metabolic autotrophy and xylene degradation.

Abstract

Most marine CO₂-fixing microorganisms remain uncultivated due to strong culture bias and low throughput of conventional approaches, which fail to link in situ function with isolated strains and render slow-growing or low-abundance taxa virtually inaccessible. This study presents an integrated single-cell workflow that incorporates ¹³C-NaHCO₃ labeling, high-throughput flow-mode Raman-activated cell sorting (RACS) and microwell cultivation for the isolation of active CO₂-fixing bacteria from the Yellow Sea. Function-guided sorting was achieved by monitoring the ¹³C-induced Raman shifts of carotenoids (ν₁ band: ∼1507 to ∼ 1503.78 cm⁻¹ at 24 h). Genomic and physiological analyses identified Paraburkholderia aromaticivorans FR-4 as a novel facultative chemoautotrophic nitrite-oxidizing bacterium (NOB). Its genome encodes complete nitrite oxidation and Calvin cycle pathways, together with key carbon acquisition genes (carbonic anhydrase, bicarbonate transporter). FR-4 grows autotrophically using NO₂⁻ as the electron donor and CO₂/HCO₃⁻ as the carbon source, confirming its ability to couple nitrite oxidation with carbon fixation, while retaining metabolic flexibility for heterotrophic growth. By directly linking in situ carbon-fixing activity, genotype, and phenotype, this workflow provides a targeted strategy for exploring elusive marine CO₂-fixing bacteria and overcomes critical limitations of conventional cultivation.