G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Prospect 100 let Vladivostoku 159, Vladivostok, 690022, Russia.
G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Prospect 100 let Vladivostoku 159, Vladivostok, 690022, Russia.
Carbohydr Res. 2019 Oct 1;484:107776. doi: 10.1016/j.carres.2019.107776. Epub 2019 Aug 9.
Inhibiting effects of sulfated steroids from marine sponges of Halichondriidae family: halistanol sulfate, topsentiasterol sulfate D and chlorotopsentiasterol sulfate D were investigated on three different types of enzymes degrading polysaccharides of brown algae: endo-1,3-β-d-glucanase GFA, fucoidan hydrolase FFA2 and bifunctional alginate lyase ALFA3 from marine bacterium Formosa algae KMM 3553, inhabiting thalli of brown alga Fucus evanescens. This is the first research, devoted to influence of a marine natural compound on three functionally related enzymes that make up the complex of enzymes, necessary to degrade unique carbohydrate components of brown algae. Alginic acid, 1,3-β-D-glucan (laminaran) and fucoidan jointly constitute practically all carbohydrate biomass of brown algae, so enzymes, able to degrade such polysaccharides, are crucial for digesting brown algae biomass as well as for organisms surviving and proliferating on brown algae thalli. Halistanol sulfate irreversibly inhibited native endo-1,3-β-D-glucanases of marine mollusks, but reversibly competitively inhibited recombinant endo-1,3-β-d-glucanase GFA. This fact indicates that there are significant structural differences between the enzymes of practically the same specificity. For alginate lyase and fucoidan hydrolase halistanol sulfate was irreversible inhibitor. Topsentiasterol sulfate D was less active inhibitor whereas chlorotopsentiasterol sulfate D was the strongest inhibitor of enzymes under the study. Chlorotopsentiasterol sulfate D caused 98% irreversible inhibition of GFA. Chlorotopsentiasterol sulfate D also caused reversible and 100% inhibition of ALFA3, which is unusual for reversible inhibitors. Inhibition of FFA2 was complete and irreversible in all cases.
从厚皮海绵科（Halichondriidae）海洋海绵中提取的硫酸化甾体化合物——硫酸岩沙甾醇、硫酸托普替甾醇 D 和硫酸氯托普替甾醇 D，对三种不同类型的褐藻多糖降解酶具有抑制作用：来自海洋细菌 Formosa algae KMM 3553 的内切 1,3-β-D-葡聚糖酶 GFA、褐藻胶裂解酶 FFA2 和具有双功能的褐藻酸裂解酶 ALFA3。这是首次研究海洋天然化合物对构成酶复合物的三种功能相关酶的影响，该酶复合物对于降解褐藻特有的碳水化合物组成部分是必需的。褐藻酸、1,3-β-D-葡聚糖（昆布多糖）和褐藻胶共同构成了褐藻几乎所有的碳水化合物生物质，因此，能够降解这些多糖的酶对于消化褐藻生物质以及对于在褐藻藻体上生存和增殖的生物都是至关重要的。硫酸岩沙甾醇不可逆地抑制了海洋软体动物的天然内切 1,3-β-D-葡聚糖酶，但可逆地竞争性抑制了重组内切 1,3-β-D-葡聚糖酶 GFA。这一事实表明，具有几乎相同特异性的酶之间存在显著的结构差异。对于褐藻酸裂解酶和褐藻胶水解酶，硫酸岩沙甾醇是不可逆抑制剂。硫酸托普替甾醇 D 的抑制活性较弱，而硫酸氯托普替甾醇 D 是研究中酶的最强抑制剂。硫酸氯托普替甾醇 D 导致 GFA 发生 98%的不可逆抑制。硫酸氯托普替甾醇 D 还导致 ALFA3 的可逆和 100%抑制，这对于可逆抑制剂来说是不寻常的。在所有情况下，FFA2 的抑制作用都是完全和不可逆的。
