The most striking characteristics:特点 一 Catalytic power(催化高效性) Specificity(选择性) Chemical nature: 一Proteins蛋白质(Nearly all known enzymes are proteins,but proteins are not an absolute monopoly on catalysis); Catalytically active RNA molecules a biocatalyst early in evolution (Section 2.2.2)The most striking characteristics：特点 － Catalytic power （催化高效性） － Specificity （选择性） Chemical nature: － Proteins 蛋白质 (Nearly all known enzymes are proteins, but proteins are not an absolute monopoly on catalysis); － Catalytically active RNA molecules : a biocatalyst early in evolution (Section 2.2.2)