不同氮源对刺芹侧耳谷氨酰胺合成酶的酶活力及基因表达影响

The gene transcription and enzymatic activity on glutamine synthetase by different nitrogen cultivated from Pleurotus eryngii

谷氨酰胺合成酶(GS)是真菌氮素代谢的关键酶之一。为探究氮源的类型和浓度对其活性的调控,采用添加单一氮源成分(硫酸铵、硝酸钠、尿素)的基本培养基培养了刺芹侧耳国森一号菌株,并对培养过程中菌丝生物量和谷氨酰胺合成酶的酶活力进行了测定。荧光定量PCR结果显示尿素和NH_4^+均可以抑制GS基因表达水平以及GS酶活力; NO_3^-可以提高GS基因表达水平和GS酶活力,但是刺芹侧耳利用NO_3^-氮源生产菌丝生物量的能力较差。

Glutamine synthetase(GS)is a central enzyme of nitrogen metabolism in fungi.A single nitrogen of minimal medium was designed to investigate the type and concentration of nitrogen source and the regulation of GS activity in culture the mycelia of Pleurotus eryngii.The transcription of PE-GS was measured by Real Time RT-PCR and the data of enzymatic activity of GS and the biomass of Pleurotus eryngii were analyzed.Fluorescence quantitative PCR showed that both urea and NH+4 could inhibit GS gene expression level and GS enzyme activity.NO-3 could improve GS gene expression level and GS enzyme activity,but the ability to produce mycelium biomass with NO-3 nitrogen source was poor in Pleurotus eryngii.