Studies on the production of Porphyrae yezoensis reeds tolerant to the red rot disease by the gene transduction of anti-Pythium protein

在本研究中，我们进行了对紫腐霉抗真菌蛋白的筛选，以建立耐赤腐病的条斑腐霉新品种，并从有里亚克海分离到13株对紫斑腐霉具有细胞壁降解活性的细菌。假单胞菌属。其中活性最强的菌株PE2具有降解甲壳素、β-1，3；1，4-葡聚糖和β-1，3-葡聚糖的活性，并通过这些酶的表达克隆了这些基因。当我们分析这些基因时，已经证明这些蛋白具有与几种多糖具有不同结合活性的功能区，并与一些多糖特异结合。在这些酶中，β-1，3(4)-葡聚糖酶A被发现对细胞壁的降解最重要。更重要的是，当我们提纯和鉴定抗P。从海洋细菌分离株Septomyces sp.的培养上清液中分离到一种卟啉蛋白(SAP)。AP77、SAP被证实有三个亚基，并且这些亚基与已知蛋白质有很高的同源性。SAP的作用方式可能与孢囊霉细胞膜的通透性有关，因此，本研究证明了上述酶和抗真菌蛋白对于通过这些蛋白的基因转导来建立条斑病菌的抗病品种是非常有用和可望的。

In the present study, we conducted to screen the antifungal proteins against Pythium porphyare to establish the new breeds of Pophyrae yezoensis tolerant to the red rot disease, and isolated 13 strains of bacteria with the cell wall degrading activity to P. porphyare from the Ariake Sea. Pseudomoas sp. PE2, the most potent active bacterium showed chitin, β-1,3;1,4-glucan, and β-1,3-glucan degrading activities and then these genes were cloned by the expression of these enzymes. When we analyzed these genes, these proteins have been proved to have the functional regions with a variety of binding activities to several polysaccharides and specifically bound to some polysaccharides. Among these enzymes, β-1,3(4)-glucanase A has been found to be most important for the cell wall degradation. More over, when we purified and characterized the anti-P. porphyare protein (SAP) from the culture supernatant of the marine bacterial isolate, Sreptomyces sp. AP77, SAP was proved to have three subunits and the homologies of these subunits are very high to the known proteins. The mode of action of SAP seems to be related to the permeability of cell membrane of P.porhyrae.Thus, the present study proves that above enzymes and antifungal proteins are very useful and expectable to establish the disease-tolerant breeds of P.yezoensis by the gene transduction of those proteins.