水霉拮抗菌HJ010拮抗物质代谢分析

Analysis of metabolic antagonists against Saprolegnia by antagonistic bacteria HJ010

水霉病是鱼体因水霉菌寄生所感染的疾病,发生广泛,危害较大,目前尚无很好的防治方法。以从河鲈肌肉中分离获得的一株水霉拮抗菌HJ010为实验材料,探讨了水霉拮抗菌的拮抗机制,初步定性了拮抗活性物质,为水霉病的生物防治奠定基础。研究结果显示,HJ010对水霉菌的菌落形成和孢子萌发都有明显抑制效应,其拮抗活性不稳定,可以随着传代丧失拮抗活性,但经水霉菌丝诱导可使丧失的拮抗活性恢复;该菌的拮抗机制是在水霉病原菌的诱导下,将代谢拮抗物质分泌到胞外发挥拮抗效应。拮抗活性物质对低pH、高温和胰蛋白酶敏感,初步定性为小分子肽类。

Saprolegniasis is ageneral and serious disease in fresh water fish affected by the water mould and is not right method of control.A kind of water mould HJ010 from the muscle of perch was acqnired and studied the primary mechanism of antagonism the Saprolegnia.The results indicated that HJ010 inhibited the sporegermination and colony development of Saprolegnia.Though the strain had not stable antagonistic ability,it was easy renewed induced by the hypha of Saprolegnia.The mechanism of resistance was that the induced water moulds were secreted the antagonistic substance to defend the fish.The resistant substance was a kind of peptide in low molecular weight,which was sensive to low pH,high temperature and trysin.