Fig. 2

Tensile testing of mycelial material. Material discs were dried and then (A) cut into strips, which were (B) mounted in a paper frame which was then (C) mounted on load-frame for testing. Details in Methods. Typical stress-strain curves for mycelial material generated from the (D) control (A1405) and (E) ΔmpkA (A1404) fungal mutant. In both cases, five test strips were cut from the center of a single disc of mycelial material. Numbers on each graph indicate the relative position of where coupons (panel A) were cut from the mycelial material. Positions 1–5 were immediately adjacent to each other, with position 3 in the middle of the material disk. For both fungal genotypes, the material shows linear elasticity before failure. Mechanical properties determined from stress-strain testing (n = 15) of material generated from control (A1405) and ΔmpkA (A1404) mutant. (F) Average Young’s modulus, (G) ultimate tensile strength and (H) strain at failure