The 10¹³–10¹⁴ microorganisms present in the human gut (collectively known as the human gut microbiota) dedicate substantial percentages of their genomes to the degradation and uptake of carbohydrates, indicating the importance of this class of molecules. Carbohydrates function not only as a carbon source for these bacteria but also as a means of attachment to the host, and a barrier to infection of the host. In this Review, we focus on the diversity of carbohydrate-active enzymes (CAZymes), how gut microorganisms use them for carbohydrate degradation, the different chemical mechanisms of these CAZymes and the roles that these microorganisms and their CAZymes have in human health and disease. We also highlight examples of how enzymes from this treasure trove have been used in manipulation of the microbiota for improved health and treatment of disease, in remodelling the glycans on biopharmaceuticals and in the potential production of universal O-type donor blood.

10 ¹³ –10 ¹⁴存在于人类肠道中的微生物（统称为人类肠道微生物群）将其基因组的很大一部分用于碳水化合物的降解和摄取，表明此类分子的重要性。碳水化合物不仅作为这些细菌的碳源，而且作为附着在宿主上的一种方式，以及宿主感染的屏障。在这篇综述中，我们关注碳水化合物活性酶 (CAZymes) 的多样性、肠道微生物如何利用它们进行碳水化合物降解、这些 CAZyme 的不同化学机制以及这些微生物及其 CAZyme 在人类健康和疾病中的作用。我们还重点介绍了这个宝库中的酶如何被用于控制微生物群以改善健康和治疗疾病的例子，