Journal: Nature Communications

Article Title: Exploring single-cell biosynthetic noise and dynamics for enhanced betaxanthin production in Escherichia coli

doi: 10.1038/s41467-025-67733-1

Figure Lengend Snippet: a The betaxanthin biosynthetic pathway. L-DOPA is provided to the cell media and is converted to betalamic acid by DOD which is fused to mCherry. Betalamic acid spontaneously reacts with primary amines to form yellow fluorescent betaxanthins. b Microfluidics chip and representative image of a single chamber within the microfluidics chip where the cells were maintained at the steady state. P1 is the inlet of cell culture, P2 is the inlet of fresh media, and P3 is the outlet of waste. c Representative time-lapse fluorescence microscopy images for measuring single-cell growth (top), protein level (middle), and metabolite level (bottom). Source data are provided as a Source Data file.

Article Snippet: Illumination for fluorescence was provided by a white light LED source (X-Cite 120 LED, Lumen Dynamics, Mississauga, ON, Canada) transmitted through fluorescence filter cubes (DS-Red channel: excitation: 540/551 nm, emission: 567/642 nm; YFP channel: excitation: 490/510 nm, emission 520/550) and an oil immersion 100× objective (Nikon).

Techniques: Cell Culture, Fluorescence, Microscopy

Journal: Nature Communications

Article Title: Exploring single-cell biosynthetic noise and dynamics for enhanced betaxanthin production in Escherichia coli

doi: 10.1038/s41467-025-67733-1

Figure Lengend Snippet: a Schematic of the in vivo Egos circuit. FmdA was placed downstream of a DOD-mCherry fusion with an RBS library to couple DOD expression noise with ammonium availability. b RBS sequences and their corresponding translation initiation rates of the four Egos variants. c , d Representative single-cell fluorescence microscopy images with 1 μm scale bar showing mCherry and betaxanthin levels for the open-loop control and each Egos variant. e , f Probability density distributions of protein (mCherry) and metabolite (betaxanthin) concentrations calculated from fluorescent microscopy. g Growth curves of Egos variants and the open-loop control (lacking fmdA ) in formamide-based selective medium. h Quantification of total betaxanthin titer. Data represents the mean ± s.d. of biological replicates ( n = 3). ** indicates p ≤ 0.01 ( p = 0.0073 for Egos4), and *** indicates p ≤ 0.001 ( p = 0.00039 for Egos2 and p = 0.00027 for Egos3) from two-tailed t -test. Source data are provided as a Source Data file.

Article Snippet: Illumination for fluorescence was provided by a white light LED source (X-Cite 120 LED, Lumen Dynamics, Mississauga, ON, Canada) transmitted through fluorescence filter cubes (DS-Red channel: excitation: 540/551 nm, emission: 567/642 nm; YFP channel: excitation: 490/510 nm, emission 520/550) and an oil immersion 100× objective (Nikon).

Techniques: In Vivo, Expressing, Fluorescence, Microscopy, Control, Variant Assay, Two Tailed Test