甘氨酸氮源对大肠杆菌代谢的影响

The effects of glycine as nitrogen source on the metabolism of E.coli

在全合成培养基中,以甘氨酸为限制氮源,利用GC-MS分析方法对E.coli的野生型菌株Y1.1566及其琥珀酸脱氢酶基因缺失突变株ΔsdhAB(S)两株菌进行胞内代谢产物分析,通过应用多变量统计分析发现在两株菌代谢产物中至少8种化合物发生显著变化,其中以D-葡萄糖苷变化最为显著。对检测到的细胞内主要氨基酸进行相关分析后发现,脯氨酸、异亮氨酸和谷氨酰胺之间的关系发生显著变化,其机制可能为适应渗透压改变的需要。

A mutant of E.coli with deletion of ΔsdhAB（S） and its wild-type stain Y 1.1566 were cultured in the synthetic mineral medium with glycine as limited nitrogen source.GC-MS method was employed to profile the intercellular metabolites of the two strains under glycine nitrogen-limitation and multivariable data analysis was applied to the acquired data.It was found that 8 representative metabolites were different in the two stains.D-Glucopyranoside showed the largest contribution to the strain differentiation.Correlation analysis of amino acids indicated that relationship among proline,isoleucine and glutamic acid was changed greatly.The mechanism may be adaptation to high osmotic pressure.