醋酸钙不动杆菌的分离鉴定及溶藻特性

摘要

淡水微囊藻水华不仅造成水体动植物缺氧死亡，而且释放藻毒素，影响人类和其它动物的健康。利用液体感染技术，从河南省平顶山市白龟山水库分离一株能够溶解铜绿微囊藻PCC 7806的溶藻菌，命名为溶藻菌5，16S rDNA核苷酸序列测序证实该菌株为醋酸钙不动杆菌。它具有一定的溶藻特异性，只溶解PCC 7806，对FACHB-930和斜生栅藻没有影响，能够促进衣藻和红球藻的生长。最佳溶藻体积比为1∶1。溶藻菌5的菌体和无细胞培养物均具有相同的溶藻效果。显微观察藻细胞被溶解的黄化液显示细菌并未附着在藻细胞周围，也无菌胶膜形成。表明溶藻菌5可能通过释放杀藻物质和与藻竞争营养物质两种机制溶解藻细胞。%The microcystis bloom not only result in the death of the aquatic animals due to hypoxia, but also produce mycrocystins which is harmful to the human beings and wild animals. One algicidal bacterium against toxicMicrocystis aeruginosa PCC 7806 was isolated from the Baiguishan Reservoir in Pingdingshan of Henan province using liquid infection technology and was named algicidal bacterium 5. The 16S rDNA sequence analysis indicated that this bacterium belongs toAcinetobacter calcoaceticus. It specifically removes PCC 7806 by cell lysis, but has no effect on FACHB-930 andScenedesmus obliquus. Interestingly, the growth of haematococcus andChlamydomonas reinhardtii are promoted. The algicidal effect of bacterium against PCC 7806 is better when the volume ratio of 1∶1. The thalli and cell-free filtrate shows the same lytic effect. There are no bacteria adhering to the surface of the PCC 7806. And no bacterial biofilm were observed. These results may suggest that TheA. calcoaceticusmay secrete substance and compete for nutrients to remove PCC 7806.