一株可利用甲烷的克雷伯氏菌的分离及其在甲烷检测中的应用

Isolation of a methane-utilizing Klebsiella sp.strain and its application for detecting methane

从山西太原水稻田土壤中,分离得到一株能以甲烷为唯一碳源和能源生长的菌株C611。通过生理生化特征及16SrDNA序列分析,该菌株初步鉴定为克雷伯氏菌(Klebsiella sp.)。采用响应面法优化了该菌株利用甲烷的培养条件,得到最佳培养条件为:温度24.4oC、接种量为6.7%、甲烷含量25%。以C611固定化细菌和溶氧响应仪为体系,采用电化学法研究了不同含量甲烷的响应时间以及溶氧变化与甲烷含量的关系。结果表明,菌株C611能利用甲烷,该反应体系对0～10%甲烷气体测定的响应时间小于100s;溶氧消耗量与通入甲烷气体含量呈线性关系,拟合系数(R2)为0.9994。以3%甲烷气体样品进行8次测量,测定平均值为3.09%,RSD为3.48%,相对误差为3%。表明该反应体系重现性良好,为该菌株进一步研究甲烷传感器奠定基础。

We have isolated a strain C611 that used methane as the sole carbon sources for growth from paddy soil in Taiyuan of Shanxi province. Based on the physiological characteristics and 16S rDNA sequence analysis, we identified the strain as Klebsiella sp.. We used statistic-based experimental design （RSM） to optimize the culture conditions for C611 strain. The optimum conditions were as follows： temperature of 24.4℃, inoculum volume of 6.7% and methane content of 25%. We studied the response time and the relationship between consumption of dissolved oxygen and methane gas contents with PVA-H3BO3 immobilized cell of C611 using electrochemical method. The response time was no more than 100 s of this reaction system, and the linear range of detection of methane content was from 0 to 10%. The standard gas sample 3% methane was measured by this method with the mean content value of 3.09%, RSD of 3.48%, and the relative error of 3%. Hence, it has the potential in developing biosensor for methane.