Fig. 2. Cellulose microfibrils in wild-type and CESA-deficient P. patens.

Cell walls were extracted from protonemal filaments of (A) wild-type and (B) CESA-deficient P. patens with 1 N NaOH and acetic-nitric reagent before air-drying and shadowing to reveal microfibrils. (C) Neutral carbohydrate region of 1D ¹³C CP-MAS-NMR spectra of CESA-deficient and wild-type P. patens. Identifiable ¹³C NMR shifts of cellulose (C), arabinose (A), and starch (SC) are labeled. The spectra were recorded at a ¹³C Larmor frequency of 150.7 MHz and a MAS frequency of 12 kHz. ppm, parts per million.