Table I:

Parameters of FNS model for uniaxial deformation of P22 virus shells, human Adenovirus (HAdV) capsid, and Herpes Simplex virus (HSV) capsid (see Fig. 2): Hertzian spring constant k_H, stiffness constant K_b, and force range $\widetilde{F_b}$. The parameter values are obtained from the fit of theoretical FX-curves (Eqs. (7)) to the experimental FX-spectra (Fig. 2), and theoretical profiles of p(F) to the histograms of critical forces (Eq. (13)) (Fig. 3; separated by the slash). For HAdV, two sets of values for the weak and strong mechanical responses, are reported. We also compared the theoretical values of the average critical force F_cr and average critical deformation X_cr, obtained using Eqs. (8) and (9), respectively, and the experimental values of these quantities extracted from the experimental FX-spectra (separated by the slash). Also, compared are the Young’s moduli for Hertzian deformation E_H and bending deformation E_b obtained with Eqs. (10) and (11), respectively. The values of E_b obtained using Eq. (11) and the thin shell approximation (see Discussion) are separated by a slash.

Particle	FNS model parameters			Critical forces and critical deformations		Young’s moduli
	kH, nN/nm3/2	Kb, nN/nm	$\widetilde{F_b}$, nN	Fcr, nN	Xcr, nm	EH, GPa	Eb, GPa
P22 Procapsid	0.02/0.02	0.06/0.04	0.90/0.39	0.46/0.45	9.8/10.3	0.03	0.25/(0.2–0.4)
P22 Expanded	0.06/0.06	0.18/0.18	2.07/0.64	0.90/0.92	6.2/7.5	0.12	1.86/(1.1–2.1)
HAdV weak	0.10/0.11	0.32/0.38	5.10/1.01	1.86/1.96	9.5/9.2	0.22	0.43/(0.42–0.82)
HAdV strong	0.12/0.12	0.46/0.50	9.91/2.12	3.50/3.80	12.8/13.4	0.27	0.62/(0.6–1.2)
HSV	0.07/0.07	0.30/0.30	7.01/2.31	2.60/2.72	14.0/14.4	0.17	10/(3.0–5.9)