微囊藻水华附生菌的代谢特征及对微囊藻生长的影响

为研究附生细菌对蓝藻水华细胞微环境的影响,从微囊藻水华中分离出34株藻附生细菌,研究其产酶能力.对氮代谢相关的酶活性测定结果显示:其中13株菌具有蛋白酶活性,5株菌具有较强的氨氮脱除能力,1株菌具有强烈的硝酸还原酶活性;4株菌具有较高的碱性磷酸酶活性;11株菌具有产脂酶的活性.通过菌和藻共同培养的方法,观察菌对微囊藻生长的影响,结果显示,有11株菌表现出较明显的促藻生长作用,占总筛选菌株总数的32%;有3株菌表现出较显著的抑制藻生长的作用,占总筛选菌株总数的9.9%.附生菌产酶能力与生长相关性的分析显示,促进微囊藻生长的附生菌都具有蛋白酶或脂酶活性.

Metabolic characteristics and effects on Microcystis growth of attached bacteria of Microcystis blooms

To study the effects of attached bacteria on the microenvironment of Microcystis cells of blooms, thirty-four attached bacterial strains were isolated from Microcystis colonies sampled from 4 different bloom samples, and enzyme-producing abilities of the isolated strains were measured. Measuring of nitrogen metabolism enzymes showed that 13 strains could hydrolyze casein, 5 strains could effectively remove ammonia, and 1 strain had a strong nitrate reductase activity. Measuring of phosphorus metabolism enzymes displayed 4 strains with phosphates' activity. The measurement also showed 11 strains with esterase activity. To evaluate the effects of the bacterial strains on the growth of Microcystis, each isolated strain was co-cultured with Microcystis. The results showed that 11 strains could obviously promote Microcystis growth,took up 32% of the total isolates; three strains obviously inhibited the growth, took up 9.9% of the total isolates. Relationship of enzyme production ability and effects on Microcystis growth revealed that the growth-promoting strains were case in aseor esterase-producing strains.