Abstract
Sustained autocatalysis coupled to compartment growth and division is a key step in the origin of life, but an experimental demonstration of this phenomenon in an artificial system has previously proven elusive. We show that autocatalytic reactions within compartments—when autocatalysis, and reactant and solvent exchange outpace product exchange—drive osmosis and diffusion, resulting in compartment growth. We demonstrate, using the formose reaction compartmentalized in aqueous droplets in an emulsion, that compartment volume can more than double. Competition for a common reactant (formaldehyde) causes variation in droplet growth rate based on the composition of the surrounding droplets. These growth rate variations are partially transmitted after selective division of the largest droplets by shearing, which converts growth-rate differences into differences in droplet frequency. This shows how a combination of properties of living systems (growth, division, variation, competition, rudimentary heredity and selection) can arise from simple physical–chemical processes and may have paved the way for the emergence of evolution by natural selection.
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Data availability
All data are available in the main text, Source Data or Supplementary Information. Due to the large number of raw image files, these files are available from the corresponding authors on reasonable request. Source data are provided with this paper.
Code availability
The annotated code to measure droplet volume and fluorescence and to identify neighbouring droplets is provided as a Matlab 2021b bundle (using the image analysis Toolbox) as Supplementary Code 8 and at https://doi.org/10.5281/zenodo.7130398 (ref. 64) and https://zenodo.org/record/7130398. The annotated code for the toy model and modelling of probabilistic droplet division regimes is available as a Jupyter bundle programmed with IPython 7.19.0 based on Python 3.8.5, provided as a downloadable folder as Supplementary Code 9 and at https://doi.org/10.5281/zenodo.7140351 (ref. 65) and https://zenodo.org/record/7140351.
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Acknowledgements
We thank A. Szilágyi for helpful comments on the manuscript, D. Schnettler Fernández for assistance with bulk formose reaction experiments and O. Beyssac and A. Percot for assistance with the fluorescence analysis of droplets. This work was supported by the European Union Seventh Framework Program (FP7/2007–2013, grant agreement no. 294332 EvoEvo; A.D.G., E.S.), the OCAV project from PSL University (A.D.G., P.N.), the Défi Origines CNRS program (P.N.), Institut Pierre-Gilles de Gennes (équipements d’excellence, ‘Investissements d’avenir’ program ANR-10-EQPX-34; A.D.G., P.N.), Paris en Résonance (équipement d’excellence ‘Investissements d’avenir’ program ANR-10-EQPX-09; F.F., P.P.), the ‘France 2030’ program (ANR-22-EXOR-0013; A.D.G., P.N.), the research infrastructure Infranalytics, FR 2054 CNRS (F.F., P.P., E.L.), the SACERDOTAL project (ANR-19-CE06-0010-01; L.J.), the ATTRACT Project EmLife (E.S.), The Volkswagen Foundation (initiative ‘Leben? – Ein neuer Blick der Naturwissenschaften auf die grundlegenden Prinzipien des Lebens’, project ‘A unified model of recombination in life’; E.S.), The National Research, Development and Innovation Office (NKFIH, Hungary) K119347 (E.S.) and GINOP-2.3.2-15-2016-00057 (E.S.) research grants, a donation from Jonathan Rothberg for artificial life research (A.D.G.) and a Human Frontier Science Program post-doctoral fellowship (R.T.-M.). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.
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Conceptualization and funding acquisition were carried out by L.J., E.S., P.N. and A.D.G. Experimentation was performed by H.L., A.B., R.T.-M., J.K., A.F., G.W., C.J., A.A., E.L., F.F. and P.P. Data analysis was carried out by H.L., A.B., R.T.-M., J.K., A.F., G.W., C.J., A.A., E.L., F.F., P.P., L.J., E.S., P.N. and A.D.G. The manuscript was written by H.L., A.B., R.T.-M., J.K., A.F., G.W., C.J., A.A., E.L., F.F., P.P., L.J., E.S., P.N. and A.D.G.
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Extended data
Extended Data Fig. 1 Detailed picture of the formose reaction system.
The formose reaction system comprises several autocatalytic cycles58, making sugars up to at least C7, Cannizzaro, oligomerization, hydration, cyclization and acid-base reactions The sub-set of reactions considered in the toy model of the formose reaction is indicated (yellow box). The reaction is catalysed by a base (in our experiments the superbase TMG) and Ca2+ (not shown). Aldol and tautomerization reactions (brown boxes), and hydration and cyclization reactions (pink boxes) are also indicated. The formose reaction system is modulated by a number of competing processes, including the Cannizzaro reaction (blue boxes), superbase hydrolysis (green boxes), the Eschweiler-Clarke reaction (orange box), the Mannich reaction (light blue box) and dynamic equilibria due to hydration and oligomerization (purple boxes).
Extended Data Fig. 2 Measurement and modelling of bulk formose reaction kinetics.
a, Formaldehyde (C1) concentration measured using the Nash method (conversion of formaldehyde to Hantzsch pyridine)63 versus time for three independent bulk reactions using standard formose reagents and 0.2 M C2, incubated at 40 °C (Nash data) plus the curve for the best fit of the toy model (best fit) (\({k}_{{add}}\) = 2.8 M−1.min−1 and \({k}_{{cleave}}\) = 0.06 min−1), and curves with \({k}_{{add}}\) and \({k}_{{cleave}}\) increased and decreased by 2-fold, and with \({k}_{{add}}\) increased by 4-fold. Note that the best overall fit (black curve) tends to slightly underestimate formaldehyde consumption between 5 to 10 minutes, whereas a 4-fold increase in \({k}_{{add}}\) (dotted black curve) more closely predicts the data. This indicates that \({k}_{{add}}\) is not determined accurately within this range, consistent with the experimental data for coupled formose droplets where the best fit of the toy model is found with a 4-fold increase in \({k}_{{add}}\) (Fig. 1e). These fitted values are consistent with those determined previously under similar conditions25. In particular, we recover the ratio \({k}_{{add}}/{k}_{{cleave}}={k}_{1}/{k}_{3}=\) 47. We also have \({{k}_{{add}}=[{{\rm{OH}}}^{-}]k}_{1}\) and \({{k}_{{cleave}}=[{{\rm{OH}}}^{-}]k}_{3}\) from25, where \({k}_{1}=\,\) 2.98 M−2 min−1 and \({k}_{3}=\) 0.2 M−1min−1. We recover our fitted values for [OH−] = 0.44 M, consistent with our conditions with 1 M of the superbase TMG where \(\left[{{\rm{OH}}}^{-}\right]\approx \,\) 1 M. b, As a, but showing the best fit of the toy model without and with the Cannizzaro reaction (no Cannizzaro and Cannizzaro, respectively) with the rate constant \({k}_{{can}}\) = 5.6 × 10−3 [OH−] = 2.5 × 10−3 M−1 min−1 from25 using [OH−] = 0.44 M for consistency as above. c, Density of glycolaldehyde (C2) as a function of concentration, showing the linearity of excess density with concentration. See also Source Data.
Extended Data Fig. 3 Modelling of transport of solutes and solvent between droplets in 1D droplet arrays.
Droplet volume vs. time for pairs of droplets containing high and low concentrations of solute using the transport model with the permeability of water through the oil phase, \({P}_{{H}_{2}O}L\) = 600 mol min−1 µm−1 (Methods and Supplementary Text). a, With different values of \({P}_{{C}_{1}}/{P}_{{H}_{2}O}\), where \({P}_{{C}_{1}}\) is the permeability of the solute formaldehyde (C1) through the oil phase, 20 µm inter-droplet distance (center-to-center separation) and 0.8 M C1 (red lines) and 0.08 M C1 (blue lines). b, As a, but with 8 M C1 (red lines) and 0.8 M C1 (blue lines). c, With solutes of different molar volume, corresponding to formaldehyde (C1), glycolaldehyde (C2), and sugars with 3 to 12 carbons (C3, C4, C6 and C12) (see Supplementary Table 2) at 0.8 M (red lines) and 0.08 M (blue lines) concentration, \({P}_{{Cn}}/{P}_{{H}_{2}O}=0.001\) and 20 µm inter-droplet distance. d, With different inter-droplet distances (40, 30, 20 and 8 µm), \({P}_{C2}/{P}_{{H}_{2}O}=0.001\) and 0.8 M C2 (red lines) and 0.08 M C2 (blue lines).
Extended Data Fig. 4 Measurement of transport of solutes and solvent between droplets in 1D droplet arrays.
Plots of droplet volume versus time from 1D droplet arrays in which alternating droplets contain a high and low concentration of solute. Solutes formaldehyde (C1), glycolaldehyde (C2), glyceraldehyde (C3), threose (C4), xylose (C5), sucrose (C12) and methanol (MeOH) were analyzed. For each condition, the volume of a representative single droplet and the mean volume of its two nearest neighbors is shown. Data for all droplets and center-to-center droplet separations of 40 µm, 30 µm, 20 µm, 14 µm and 8 µm are shown in Supplementary Fig. 2 and confirm the dependence of osmotically driven volume changes on inter-droplet distance found in the model (Extended Data Fig. 3d). a, Solute concentrations of 0.8M (red dots) and 0.08M solute (blue dots) for C1 to C12 and 15% (red dots) and 0% (blue dots) for MeOH, with 20 µm inter-droplet spacing. Meaningful volume changes were only detected for C3, C4, C5 and C12, indicating that \({P}_{{C}_{3-12}}/{P}_{{H}_{2}O}\,\le 0.01\) (as in the model similar volume changes are only observed for \({P}_{{C}_{1}}/{P}_{{H}_{2}O}\,\le 0.01\), see Extended Data Fig. 3a, and different molar volumes of solutes has only a minor effect, see Extended Data Fig. 3c). Indeed, the absence of meaningful volume change for C2 implies that \({P}_{{C}_{3-12}}/{P}_{{C}_{2}}\le 0.01\) (as no meaningful volume change is observed in the model with \({P}_{{C}_{1}}/{P}_{{H}_{2}O}=1.0\), see Extended Data Fig. 3a). b, Solute concentrations of 8M (red dots) and 0.8M solute (blue dots) for C1 with 20 µm inter-droplet spacing and C2 with inter-droplet distances of 40 µm, 30 µm, 20 µm, 14 µm and 8 µm. No meaningful volume change was observed for C1, indicating that \({P}_{{C}_{1}}\ge {P}_{{H}_{2}O}\) (as no meaningful droplet volume changes are observed with the model when \({P}_{{C}_{1}}/{P}_{{H}_{2}O}\ge 1.0\), see Extended Data Fig. 3b). However, important volume change was observed for C2, and the curves show the best fit for \({P}_{{H}_{2}O}\) and \({P}_{{C}_{2}}\) using the transport model. c-d, \({P}_{{H}_{2}O}\), and \({P}_{{C}_{2}}\) by fitting experimental data for droplets containing C2 to the transport model (see panel b). c, \({P}_{{H}_{2}O}\) as a function of the inter-droplet distance, \(L\) (left panel) and \({P}_{{H}_{2}O}L\) as a function of \(L\) (right panel). d, \({P}_{{C}_{2}}\) as a function of the inter-droplet distance, \(L\) (left panel) and \({P}_{{C}_{2}}L\) as a function of \(L\) (right panel). In panels c and d each small blue point corresponds to data from a single droplet and the mean volume of its two nearest neighbours and the large black point is the mean value for all data points. The values of \({P}_{{H}_{2}O}\) and \({P}_{{C}_{2}}\) are inversely proportional to \(L\), and \({P}_{{H}_{2}O}L\) and \({P}_{{C}_{2}}L\) are independent of \(L\). The mean \({P}_{{H}_{2}O}L\) is 532±148 mol min−1 µm−1 (SD, n = 43) and the mean \({P}_{{C}_{2}}L\) is 32±5 mol min−1 µm−1 (SD, n = 43). The mean value of \({P}_{{C}_{2}}/{P}_{{H}_{2}O}\) is 0.063±0.013 (SD, n = 43). Assuming \({P}_{{C}_{3-12}}/{P}_{{C}_{2}}\le 0.01\) (see above) this implies that \({P}_{{C}_{3-12}}/{P}_{{H}_{2}O}\,\le 0.0006\). See also Source Data.
Extended Data Fig. 5 Characterization of the formose reaction in droplets.
a-b, Characterization of change in droplet volume in 1D droplet arrays. Plots of droplet volume versus time for alternating droplets containing standard formose reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1M TMG) with 0.2M glycolaldehyde (C2 0.2M, red dots) and no glycolaldehyde (C2 0M, blue dots), at 40 °C, but a, without CaCl2 (No calcium), or b, without CaCl2 and without TMG (No calcium, no TMG), with center-to-center droplet separation of 20 µm. For each condition, the volume of a representative single droplet and the mean volume of its two nearest neighbors is shown. Data for all droplets and center-to-center droplet separations of 30 µm, 20 µm, 14 µm and 8 µm are shown in Supplementary Fig. 3. c-e, Pendant drop interfacial tension measurements. Interfacial tension measured between aqueous drops containing either, standard formose reagents plus 0.2 M glycolaldehyde (C2 0.2M), standard formose reagents (C2 0M) or 1 M formaldehyde (no calcium, no TMG) and c, HFE-7500, d, HFE-7500 containing 0.5% 008-FluoroSurfactant, or e, HFE-7500 containing 2.0% 008-FluoroSurfactant. The mean values at each time point are connected by lines and the vertical lines represent ±1 s.d. of the samples at each time point (n = 3 to 5). f, bright-field image of droplet size fractionation by pinched flow (see also Supplementary Video 7) to separate large and small droplets for mass spectroscopy (see Extended Data Fig. 6). See also Source Data.
Extended Data Fig. 6 Mass spectroscopy of the formose reaction in droplets and in bulk.
Mass spectrum of a, droplets containing standard formose reagents plus 0.2 M glycolaldehyde (C2 droplets) after 1 h incubation at 40 °C. b, Mass spectra of b, large (growing) and c, small (shrinking) droplets after 1 h incubation at 40 °C of a 1:1 mixture of droplets containing standard formose reagents plus 0.2 M glycolaldehyde (C2 droplets) or with no glycolaldehyde (no-C2 droplets) and pinched-flow size fractionation of droplets (see Extended Data Fig. 5f). A priori large droplets are C2 droplets and small droplets are no-C2 droplets. d, bulk reaction of standard formose reagents plus 0.2 M glycolaldehyde (C2) after 1 h incubation at 40 °C. e, bulk reaction of 1 M C1 and 0.2 M C2 (no TMG, no CaCl2) after 1 h incubation at 40 °C. f, bulk reaction with standard formose reagents (no C2) after 1 h incubation at 40 °C. Values of m/z and peak assignments of Cn sugars are indicated (n = number of carbon atoms). See also Supplementary Figs. 4–12 and Supplementary Table 3.
Extended Data Fig. 7 Kinetics of droplet volume and progress of the formose reaction in bulk and in droplets, measured by fluorescence spectroscopy and fluorescence microscopy.
a-c, fluorescence spectroscopy measurements in bulk (excitation 400 nm, emission spectra 450 to 690 nm, time 0 min to 160 min). a, standard formose reaction (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M of 1,1,3,3-tetramethylguanidine [TMG]) supplemented with 0.2 M glycolaldehyde (C2)). b, control reaction (no C2). c, control reaction (no TMG and no CaCl2). Insets in a-c show fluorescence versus time of the corresponding experiment (excitation 400 nm, emission 510 nm). d-h, Fluorescence measurements in droplets. A 1:1 ratio of 0.2 M C2 droplets and no-C2 droplets (both unlabeled) were incubated at 40 °C in a 2D droplet array. The volume and green fluorescence (excitation 390 nm, emission 515/30 nm) of n = 73 droplets was measured over time. d, droplet volume versus time. e, droplet fluorescence versus time, f, droplet fluorescence versus volume. Each red trace corresponds to a growing (a priori 0.2 M C2) droplet and each blue trace corresponds to a shrinking (a priori no C2) droplet. g, Mean volume of droplets versus number of no C2 neighbors after 136 min incubation. h, Mean green fluorescence of growing (0.2 M C2) droplets versus number of no-C2 neighbors after 136 min incubation. Data in panels g and h are presented as mean values ±1 s.d. See also Source Data.
Extended Data Fig. 8 Size-dependence of droplet growth rate.
1:2 mixtures of 51, 133 and 416 pL aqueous droplets containing the standard formose reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1M TMG) and, additionally, either 0.2 M glycolaldehyde (0.2 M C2) or no C2 (no C2) were incubated in a 2D droplet array for 1 h at 40 °C. The growth rate of 0.2 M C2 droplets is plotted against initial volume for droplets with different initial numbers of no-C2 neighbouring droplets (1 to 5). Data are presented as mean values ±1 s.d. For values for growth rate, standard deviation and number of data points, n, see Source Data.
Extended Data Fig. 9 Limit cycles in the bulk formose reaction.
a, Image of a tube containing standard formose reagents supplemented with 0.2 M C2 after one month incubation at room temperature. The reaction mixture becomes brown and tar-like. b-d, Serial transfer of the bulk formose reaction. After 24 min incubation at 40 °C, 20 µL of standard formose reagents with 0.2 M C2 was transferred into 180 µl of freshly prepared standard formose reagents, and the procedure repeated 6 rounds in total. In each round, after the 24 min incubation, a sample was taken and analyzed using the Hantzsch reaction (to measure the concentration of formaldehyde [C1]), or by NMR. b, Concentration of formaldehyde (C1) for each round of serial transfer. Relaxation is shown by the dashed line and the characteristic relaxation time, \(\tau\), is indicated. The serial transfer was performed in triplicate (n = 3). c, Concentration of formate (a product of the Cannizzaro reaction) for each round of serial transfer, determined by NMR. The inset shows the increase in formate concentration over time in each round. d, NMR spectra from 2.6 to 4.0 \(\delta\) (ppm) for each round of serial transfer. Collectively, panels b-d show that by keeping the system out of equilibrium by serial dilution there is convergence to a limit cycle corresponding to maintained autocatalysis. See also Source Data.
Extended Data Fig. 10 Microfluidic devices.
a, Device i) to produce monodisperse droplets with a defined composition. b, Device ii) to produce alternating droplets of different volume and composition and incubate these droplets in 1D arrays. c, Device iii) to incubate droplets in 2D arrays. d, Device iv) to perform a single size-dependent droplet division. e, Device v) to perform a double size-dependent droplet division. f, Device vi) to perform size-dependent sorting of droplets using pinched-flow fractionation. Larger scale designs of important features are shown in blue boxes. See Supplementary Files 1–7 for CAD files and Adobe Illustrator files for the devices.
Supplementary information
Supplementary Information
Supplementary Text, Supplementary Figs. 1–13 and Tables 1–3.
Supplementary Video 1
Formation of alternating droplets of different size and composition.
Supplementary Video 2
The hydrodynamic switch for on-demand droplet loading.
Supplementary Video 3
Droplet buffering in a 1D droplet array.
Supplementary Video 4
A one-dimensional (1D) array of aqueous droplets containing standard formose reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M TMG) during a 4-h incubation at 40 °C. The ~100-pl droplets initially contained 1 M formaldehyde (C1), 0.02 M CaCl2 and 1 M of TMG while the ~60-pl droplets contained, in addition, 0.2 M glycolaldehyde (C2).
Supplementary Video 5
Combined fluorescence and bright-field movie of a two-dimensional (2D) array of 778-pl aqueous droplets containing standard formose reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M TMG) during a 1-h incubation at 40 °C. Two populations of droplets were mixed in a 1:1 ratio: droplets additionally containing 0.2 M glycolaldehyde (0.2 M C2, unlabelled) or no glycolaldehyde (no C2, labelled with green silica nanoparticles).
Supplementary Video 6
Combined fluorescence and bright-field movie of a two-dimensional (2D) array of 81-pl aqueous droplets containing standard formose reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M TMG) during a 1-h incubation at 40 °C. Three populations of droplets were mixed in a 1:1:1 ratio: droplets with no C2, and additionally containing 0.2 M glycolaldehyde (0.2 M C2, labelled with green silica nanoparticles) or 0.05 M glycolaldehyde (0.05 M C2, labelled with red silica nanoparticles).
Supplementary Video 7
Size-dependent sorting of a 1:1 mixture of droplets containing standard formose reaction reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M TMG) supplemented with 0.02 M glycolaldehyde (0.2 M C2) or without C2 (no C2) using pinched-flow fractionation after 1-h incubation at 40 °C.
Supplementary Video 8
Fluorescence microscopy (excitation 390 nm, emission 515/30 nm) (right panel) and bright-field microscopy (left panel) of the same region of a two-dimensional (2D) array of ~100-pl aqueous droplets containing standard formose reaction reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M TMG) during a 136-min incubation at 40 °C. Unlabelled droplets containing no C2 and containing 0.2 M C2 were mixed in a 1:1 ratio.
Supplementary Video 9
Single size-dependent droplets division in a microfluidic device. Droplets over a threshold volume, vd ≈ 400 pl were divided symmetrically at the T-junction.
Supplementary Video 10
Double size-dependent droplets division in a microfluidic device. Droplets over a threshold volume vd ≈ 400 pl and ≈ 200 pl, respectively, were divided symmetrically at the first and second T-junctions.
Supplementary Video 11
Combined fluorescence and bright-field movie of a two-dimensional (2D) array of 71-pl aqueous droplets containing formose reaction reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M TMG) during a 1-h incubation at 40 °C. Droplets containing no C2 (labelled with red silica nanoparticles) and containing 0.2 M C2 droplets (unlabelled) were mixed in a 2:1 ratio.
Supplementary Video 12
Combined fluorescence and bright-field movie of a two-dimensional (2D) array of aqueous droplets containing standard formose reaction reagents (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M TMG) during a 1-h incubation at 40 °C. After single size-dependent droplet division, droplets from the experiment shown in Supplementary Movie 11 were mixed with a twofold excess of freshly prepared 140 pl no-C2 droplets (labelled with green silica nanoparticles).
Supplementary Code 1
CAD file of device (i), used to produce monodisperse droplets with a defined composition.
Supplementary Code 2
CAD file of device (ii), used to produce alternating droplets of different volume and composition and incubate these droplets in 1D arrays.
Supplementary Code 3
CAD file of device (iii), used to incubate droplets in 2D arrays.
Supplementary Code 4
Adobe Illustrator file of device (iii), used to incubate droplets in 2D arrays (to directly program the cutting plotter).
Supplementary Code 5
CAD file of device (iv), used to perform a single size-dependent droplet division.
Supplementary Code 6
CAD file of device (v), used to perform a double size-dependent droplet division.
Supplementary Code 7
CAD file of device (vi), used to perform pinched-flow size fractionation of droplets.
Supplementary Code 8
Annotated code for measurement of droplet volume and fluorescence and identification of neighbouring droplets. The code is available as a Matlab 2021b bundle (based on the Image Analysis Toolbox). Test data is available at (10.5281/zenodo.7130398)31: https://zenodo.org/record/7130398.
Supplementary Code 9
Annotated code for the toy model and modelling of probabilistic droplet division regimes. The code is available as a Jupyter bundle programmed with IPython 7.19.0 based on Python 3.8.5.
Supplementary Data 1
Source data for Supplementary Fig. 1.
Supplementary Data 2
Source data for Supplementary Fig. 2.
Supplementary Data 3
Source data for Supplementary Fig. 3.
Source data
Source Data Fig. 1
Experimental data points for panels c and e.
Source Data Fig. 2
Experimental data points, standard deviation and number of data points, n, for panels b, c, e and g.
Source Data Fig. 3
Experimental data points, confidence interval, standard deviation and number of data points, n, for panels a, c–e.
Source Data Extended Data Fig. 2
Experimental data points for all panels.
Source Data Extended Data Fig. 4
Experimental data points for all panels.
Source Data Extended Data Fig. 5
Experimental data points for panels a–e.
Source Data Extended Data Fig. 7
Experimental data points for all panels.
Source Data Extended Data Fig. 8
Experimental data points, standard deviation and number of data points, n.
Source Data Extended Data Fig. 9
Experimental data points for panels b and c.
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Lu, H., Blokhuis, A., Turk-MacLeod, R. et al. Small-molecule autocatalysis drives compartment growth, competition and reproduction. Nat. Chem. 16, 70–78 (2024). https://doi.org/10.1038/s41557-023-01276-0
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DOI: https://doi.org/10.1038/s41557-023-01276-0
