Figure 4. CrvA generates curvature by patterning cell wall insertion.
(A) QuASAR pulse-chase experiment; red indicates newly inserted PG (labeled by NADA), while green indicates old PG (HADA). See Figure S6 for further characterization of QuASAR-based findings, and Figure S3D–F for a description of the relationship between FDAA measurements and morphological models.
(B) Diagram of cell regions for QuASAR analysis.
(C–D) Integral (sum) of fluorescence intensity of new (red) and old (green) PG, separated into the outer (solid lines) and inner (dashed lines) faces. Data represent median values at each time point and error bars are 90% confidence intervals.
(C) Integral of new PG is greater along the outer face than the inner face of wild-type cells.
(D) Integral of old PG along the inner and outer faces of curved wild-type cells are indistinguishable.
(E) Asymmetry quotient of curved and straight cells. The line represents a ratio of 1, corresponding to static curvature. Data represent the median of the pairwise ratios of proportional growth of the outer face of cells to the proportional growth of the inner face of cells (εouter/εinner).
(F) Dynamic curvature is driven by a differential in exponential insertion rates between the inner and outer faces. Values are median 2D centerline curvatures, with range of predicted curvatures for wild type (blue) and ΔcrvA (yellow) cells (Equation S12). All error estimates are ± 90% bootstrap confidence intervals.