【摘要】 以无机硫（S2）-为目标污染物,从北京东沙河黑臭水体筛选出一株能够高效氧化S^2-的土著硫氧化菌,并对其进行16S rRNA测序及生理生化特性鉴定,结果表明,该菌株属于寡养单胞菌属（Stenotrophomonas）,命名为Stenotrophomonas sp.sp3.菌株sp3在温度25℃,初始pH值7.0,初始葡萄糖浓度0.25%,初始菌浓度1.00g/L时,菌株sp3对S^2-的氧化率最高.在此适宜条件下,反应60h后,菌株sp3对S^2-的最高氧化率达到86.6%.S^2-的浓度在整个氧化过程中持续下降后保持稳定,在此过程中产生了S⁰,S₂O₃^2-,SO₃^2-以及SO₄^2-这4种其它存在形态的硫.随着S^2-被氧化,SO₄^2-的浓度呈缓慢上升的趋势.利用高通量测序技术推测菌株sp3主要是通过副球菌硫氧化途径（PSO）将非稳定态的S^2-逐步转化为稳定态的SO₄^2-.在此代谢途径中,一部分S^2-被氧化为S⁰,另一部分S^2-则直接氧化为SO₃^2-;S⁰与SO₃^2-可自发反应生成S₂O₃^2-,而S₂O₃^2-发生歧化反应再释放出SO₃^2-和S⁰;反应生成的部分SO₃^2-继续直接氧化为SO₄^2-.菌株sp3在黑臭水体的水质净化过程中有一定的应用前景.更多还原

【Abstract】 Inorganic sulfur(S^2-) was used as the target pollutant, and a single strain capable of S^2--oxidizing was obtained from Dongsha river（a black-stinking river） located in Beijing. Through both of the physiological-biochemical characteristics and the 16 S rRNA sequencing experiment, this single strain was identified as Stenotrophomonas, and named as Stenotrophomonas sp.sp3. The experiment on the growth and S^2--oxidizing characteristics of this strain sp3 was then carried out. The best conditions of S^2--oxidizing were as follows: initial pH of 7.0, 25℃, initial glucose concentration of 0.25% along with initial cell concentration of 1.00 g/L. Under the above bio-oxidation conditions, the highest S^2--oxidizing ratio was arrived at 86.6% by this strain sp3 after the bio-reaction of 60 h. The concentration of S^2-decreased continually and then kept in a stable status in the whole bio-reaction process, and other sulphur chemical forms including S⁰, S₂O₃^2-, SO₃^2-and SO₄^2-were produced in this period. With the bio-oxidation of S^2-, the concentration of SO₄^2-increased slowly. High-throughput sequencing technologies were used to investigate the main metabolic pathway of S^2-bio-oxidation by this strain sp3. The paracoccus sulfur oxidation process was the possibly main metabolic pathway of S^2-（unstable valence state） to SO₄^2-（stable valence state）. It was initially concluded that a portion of S^2-was oxidized to S⁰, while other part of S^2-was directly oxidized to SO₃²; and then S⁰ reacted with SO₃^2-spontaneously to form S₂O₃^2-, while the latter was released SO₃^2-and S⁰ by the disproportionate reaction again. The SO₃^2-accumulated gradually in the system was further directly oxidized to SO₄^2-. This study indicated that this strain sp3 has potential application in water purification of the black-stinking wate bodies.更多还原