Plant cellulose microfibrils are increasingly employed to produce functional nanofibers and nanocrystals for biomaterials, but their catalytic formation and conversion mechanisms remain elusive. Here, we characterize length-reduced cellulose nanofibers assembly in situ accounting for the high density of amorphous cellulose regions in the natural rice fragile culm 16 (Osfc16) mutant defective in cellulose biosynthesis using both classic and advanced atomic force microscopy (AFM) techniques equipped with a single-molecular recognition system. By employing individual types of cellulases, we observe efficient enzymatic catalysis modes in the mutant, due to amorphous and inner-broken cellulose chains elevated as breakpoints for initiating and completing cellulose hydrolyses into higher-yield fermentable sugars. Furthermore, effective chemical catalysis mode is examined in vitro for cellulose nanofibers conversion into nanocrystals with reduced dimensions. Our study addresses how plant cellulose substrates are digestible and convertible, revealing a strategy for precise engineering of cellulose substrates toward cost-effective biofuels and high-quality bioproducts.

植物纤维素微纤维越来越多地用于生产用于生物材料的功能性纳米纤维和纳米晶体，但它们的催化形成和转化机制仍然难以捉摸。在这里，我们描述了原位长度减少的纤维素纳米纤维组装的特征，解释了天然水稻易碎秆 16 ( Osfc16)中无定形纤维素区域的高密度) 使用配备单分子识别系统的经典和高级原子力显微镜 (AFM) 技术发现纤维素生物合成中的突变体缺陷。通过使用各种类型的纤维素酶，我们观察到突变体中有效的酶促催化模式，这是由于无定形和内部断裂的纤维素链被提升为启动和完成纤维素水解成更高产量的可发酵糖的断点。此外，在体外检查了有效的化学催化模式，以将纤维素纳米纤维转化为尺寸减小的纳米晶体。我们的研究解决了植物纤维素底物如何可消化和可转化，揭示了一种将纤维素底物精确工程化为具有成本效益的生物燃料和高质量生物产品的策略。