低温对异养硝化菌Acinetobacter sp.生长代谢及群体感应影响研究
Effects of low temperature on the growth,metabolism,and quorum sensing of heterotrophic nitrifying bacteria Acinetobacter sp.
王乙舒 1李圆 1侯连刚 2陈慧萱 1侯惠敏 1王秀杰1
作者信息
- 1. 江苏科技大学环境与化学工程学院,江苏 镇江 212100
- 2. 中建一局集团建设发展有限公司,北京 100102
- 折叠
摘要
为进一步探究低温条件下HN-AD菌氮素转化机理及其群体感应系统对低温响应机制,采用GC-MS测定HN-AD过程中释放的信号分子,结果表明菌株JQ1004至少分泌包括C6-,C8-,和C10-HSL在内3种高丝氨酸内酯(AHLs),其浓度变化均随细菌浓度增加不断累积,呈现显著密度依赖性.当温度由30℃降低至10℃时,C6-和C8-HSL呈不断下降趋势,而C10-HSL变化为先上升后下降,并在20℃达到最大值10.89nmol/L,表明C10-HSL在菌株适应低温环境中发挥重要作用.低温添加10nmol/L C10-HSL可显著缩短细菌迟滞期,提高脱氮速率.20℃和10℃时添加C10-HSL使amoA表达量分别提高了35%和22%,napA表达量分别增加了14%和9.4%.C10-HSL通过提高luxR调控的受体蛋白活性来提高菌株群感能力.低温添加C10-HSL可促进胞外蛋白分泌,降低多糖含量,提高生物膜活性,进而强化其对低温恶劣环境适应能力.
Abstract
To further explore the mechanism of nitrogen transformation and quorum sensing system of HN-AD bacteria under low temperature,there were at least three AHLs signaling molecules,including C6-,C8-,and C10-HSL produced by the HN-AD bacterium JQ1004 based on the analysis of GC-MS.The concentration of AHLs showed a significant density dependence and continuously accumulated with the increase of biomass.When the temperature decreased from the optimal 30℃to 10℃,C6-and C8-HSL showed a continuous decreasing trend due to the decrease of cell concentration,while the concentration of C10-HSL increased first and then decreased,reaching a maximum value of 10.89nmol/L at 20℃,indicating that C10-HSL played a crucial role in the bacterial adaptation to low-temperature environments.Further study found that adding 10nmol/L C10-HSL at low temperature could significantly shorten the bacterial lag period and improved the nitrogen removal rate.The addition of C10-HSL at 20℃and 10℃increased the expression of amoA by 35%and 22%,respectively,while the expression of napA increased by 14%and 9.4%.C10-HSL enhanced the ability of quorum sensing of strains by increasing the receptor protein activity regulated by luxR.Adding C10-HSL at low temperature could promote extracellular protein secretion,reduce polysaccharide content,improve biofilm activity,and strengthen its adaptability to harsh low-temperature environments.
关键词
异养硝化/好氧反硝化/群体感应/低温/AHLsKey words
heterotrophic nitrification/aerobic denitrification/quorum sensing/low temperature/AHLs引用本文复制引用
基金项目
江苏省自然科学基金资助项目(BK20210896)
出版年
2024
NETL
NSTL
万方数据