Hugouvieux-Cotte-Pattat Nicole, Condemine Guy, Shevchik Vladimir E
Environ Microbiol Rep. 2014 Oct;6(5):427-40. doi: 10.1111/1758-2229.12166.
Pectate lyases are enzymes involved in plant cell wall degradation. They cleave pectin using a β-elimination mechanism, specific for acidic polysaccharides. They are mainly produced by plant pathogens and plant-associated organisms, and only rarely by animals. Pectate lyases are also commonly produced in the bacterial world, either by bacteria living in close proximity with plants or by gut bacteria that find plant material in the digestive tract of their hosts. The role of pectate lyases is essential for plant pathogens, such as Dickeya dadantii, that use a set of pectate lyases as their main virulence factor. Symbiotic bacteria produce their own pectate lyases, but they also induce plant pectate lyases to initiate the symbiosis. Pectin degradation products may act as signals affecting the plant–bacteria interactions. Bacterial pectate lyases are also essential for using the pectin of dead or living plants as a carbon source for growth. In the animal gut, Bacteroides pectate lyases degrade the pectin of ingested food, and this is particularly important for herbivores that depend on their microflora for the digestion of pectin. Some human pathogens, such as Yersinia enterocolitica, produce a few intracellular pectate lyases that can facilitate their growth in the presence of highly pectinolytic bacteria, at the plant surface, in the soil or in the animal gut.
果胶酸裂解酶是参与植物细胞壁降解的酶。它们通过β-消除机制裂解果胶，这种机制对酸性多糖具有特异性。它们主要由植物病原体和与植物相关的生物体产生，动物很少产生。果胶酸裂解酶在细菌界也很常见，要么由与植物密切共生的细菌产生，要么由在宿主消化道中发现植物物质的肠道细菌产生。果胶酸裂解酶的作用对于植物病原体（如胡萝卜软腐果胶杆菌）至关重要，这些病原体将一组果胶酸裂解酶作为其主要致病因子。共生细菌会产生自己的果胶酸裂解酶，但它们也会诱导植物产生果胶酸裂解酶以启动共生关系。果胶降解产物可能作为影响植物与细菌相互作用的信号。细菌果胶酸裂解酶对于利用死的或活的植物中的果胶作为生长的碳源也至关重要。在动物肠道中，拟杆菌属的果胶酸裂解酶会降解摄入食物中的果胶，这对于依赖其微生物群消化果胶的食草动物尤为重要。一些人类病原体，如小肠结肠炎耶尔森菌，会产生一些细胞内果胶酸裂解酶，这些酶可以在植物表面、土壤或动物肠道中，在存在高度果胶分解细菌的情况下促进其生长。
