【目的】分离并鉴定1株具有尼古丁降解能力的细菌,研究其尼古丁降解特性并对其降解基因进行分析,为尼古丁微生物降解提供基础。【方法】从烟草种植地土壤中分离1株具有尼古丁降解能力的细菌,通过16S r RNA基因和生理生化特性对该菌株进...【目的】分离并鉴定1株具有尼古丁降解能力的细菌,研究其尼古丁降解特性并对其降解基因进行分析,为尼古丁微生物降解提供基础。【方法】从烟草种植地土壤中分离1株具有尼古丁降解能力的细菌,通过16S r RNA基因和生理生化特性对该菌株进行鉴定,检测该菌株尼古丁降解率与生长量的关系,并进一步对该菌株进行尼古丁浓度耐受性测定,采用高通量测序技术对菌株进行全基因组测序,BLAST比对分析尼古丁降解相关基因。【结果】筛选到1株具有尼古丁降解能力的细菌,经鉴定命名为根癌土壤杆菌(Agrobacterium tumerficience)SCUEC1菌株,根癌土壤杆菌SCUEC1菌株尼古丁降解率可达到94.81%,该菌株在尼古丁浓度为0.50–5.00 g/L范围内生长良好且有较高的尼古丁降解能力。对根癌土壤杆菌SCUEC1菌株全基因组序列进行BLAST比对分析,推测该菌株的尼古丁降解代谢途径与中间苍白杆菌SYJ1菌株的尼古丁降解途径相似。【结论】本研究揭示了Agrobacterium tumerficienceSCUEC1菌株具备尼古丁降解特性,初步推测出尼古丁降解相关基因和降解代谢途径,为尼古丁微生物降解提供基础。展开更多
The homogeneous and controllable morphology of anhydrous magnesium carbonate(MgCO_(3))particles with excellent properties is difficult to obtain because of a variety of synthetic factors.The effect of succinic acid as...The homogeneous and controllable morphology of anhydrous magnesium carbonate(MgCO_(3))particles with excellent properties is difficult to obtain because of a variety of synthetic factors.The effect of succinic acid as a crystal modifier on the particle morphology transformation of anhydrous MgCO_(3)was investigated by the hydrothermal method.The effect of the addition of succinic acid on the particles was similar to that of temperature change.The morphology of particles with a folded diamond-like shape was gradually uniform,and the particle size was between 3.3 and 7.5μm.Anhydrous MgCO_(3)particles prepared at pH 9 could easily agglomerate,and the average particle size increased from diamond-like to cube-like as the reaction time increased.The interaction between succinic acid and magnesium ions at different concentrations was the main factor responsible for the morphological changes.The pH,temperature,and time affected the molecular motion rate and crystal growth.展开更多
基金the National Natural Science Foundation of China(grant No.U22A20434)the Foundation from Qinghai Science and Technology Department(grant No.2022-ZJ-706).
文摘The homogeneous and controllable morphology of anhydrous magnesium carbonate(MgCO_(3))particles with excellent properties is difficult to obtain because of a variety of synthetic factors.The effect of succinic acid as a crystal modifier on the particle morphology transformation of anhydrous MgCO_(3)was investigated by the hydrothermal method.The effect of the addition of succinic acid on the particles was similar to that of temperature change.The morphology of particles with a folded diamond-like shape was gradually uniform,and the particle size was between 3.3 and 7.5μm.Anhydrous MgCO_(3)particles prepared at pH 9 could easily agglomerate,and the average particle size increased from diamond-like to cube-like as the reaction time increased.The interaction between succinic acid and magnesium ions at different concentrations was the main factor responsible for the morphological changes.The pH,temperature,and time affected the molecular motion rate and crystal growth.
