印度洋可培养解有机磷细菌的多样性及解磷特性

Diversity and characteristics of culturable phosphate-solubilizing bacteria of Indian Ocean

摘要:

【目的】筛选获得印度洋海水解有机磷细菌，研究其解有机磷作用机理，初步了解该地区可培养有机磷细菌的系统发育多样性。【方法】采用卵磷脂培养基从分离自印度洋的细菌中筛选解有机磷细菌，根据16S rRNA基因序列确定获得的有机磷细菌的分类地位；同时挑选解磷效果显著的3株细菌利用液体发酵进行产酶和解磷特性分析。【结果】自916株细菌中得到99株具有解有机磷活性的细菌，分属于16个属。在以卵磷脂为其有机磷来源时，菌株India-BSP-1 (Cobetia sp.)、India-BSP-21 (Pelagibaca sp.)、India-BSP-23 (Pelagibacterium sp.)的培养液中磷酸盐(DIP)浓度曲线为N型，并且碱性磷酸酶的检测活性滞后于DIP的生成。【结论】印度洋海水中解有机磷细菌种类多样性丰富，疑似有新种；解有机磷细菌的解磷特性受DIP和碱性磷酸酶相互作用的影响。

Abstract:

[Objective] The aim of this study is to screen culturable phosphate-solubilizing bacteria from water samples of the Indian Ocean, and tackle their mechanism of regenerating phosphate from organics and their phylogenetic diversity in the region. [Methods] Phosphate-solubilizing bacteria were selected by inoculating bacteria isolated from the Indian Ocean waters onto solid lecithin medium, and the phosphate-solubilizing bacteria were identified according to their 16S rRNA genes. Three strains of high phosphate-solubilizing activities were studied for their alkaline phosphatase production and phosphate-solubilizing in fermentation liquid. [Results] A total of 99 phosphate-solubilizing strains from 16 genera were selected from the 916 available bacteria strains. The dissolved inorganic phosphate (DIP) concentration presented N-type curves in cultures of all the three active phosphate-solubilizing stains India-BSP-1 (Cobetia sp.), India-BSP-21 (Pelagibaca sp.), India-BSP-23 (Pelagibacterium sp.), and the alkaline phosphatase was detected after DIP production. [Conclusion] Phosphate-solubilizing bacteria of the Indian Ocean waters presented rich species diversity and three candidate new species. The characteristics of bacterial regeneration of phosphate from organics were influenced by both DIP and alkaline phosphatase.