产黄青霉菌响应苯氧乙酸的Ca2+信号转导机制

摘要

[目的]研究青霉素V生产过程中—Ca2+信号转导途径参与产黄青霉菌对外源侧链前体苯氧乙酸的应答机制.[方法]考察4种不同机制的Ca2+信号干扰剂[利心平、乙二醇双(2-氨基乙基醚)四乙酸、苏拉明和硫酸新霉素]对青霉素V产量和产黄青霉菌生物量的影响.运用Fluo-3/AM荧光染料对细胞进行染色,通过荧光显微镜成像和酶标仪定量检测两种方法监测胞内Ca2+浓度的变化.[结果]苯氧乙酸添加后胞内Ca2+相对含量高于对照组49.86％,而1 mmol/L磷酸酯酶C底物抑制剂硫酸新霉素的添加使得胞内Ca2+相对含量降低了53.31％,同时青霉素V产量降低78.71％,表明产黄青霉菌可通过肌醇1,4,5-三磷酸信号途径调节胞内Ca2+浓度来响应苯氧乙酸的胁迫.[结论]首次探究了Ca2+信号转导途径在产黄青霉菌对苯氧乙酸应答中的作用,为丝状真菌中Ins(1,4,5)P3-Ca2+信号转导途径的研究提供理论依据.%[Objective] We studied calcium-associated signal responses of Penicillium chrysogenum to phenoxyacetic acid.[Methods] The effects of different types of Ca2+ interference agents (Nifedipine,EGTA,Suramin and Neomycin sulfate) for penicillin V production were studied.Intracellular Ca2+ concentration was measured by Olympus System microscope and SpectraMax M2 Fluorescence Microplate Reader.[Results] Levels of intracellular Ca2+ in P.chrysogenum significantly increased (49.86％ higher than the control) at 25 h after treatment with phenoxyacetic acid (POA),whereassignificantly reduced (53.31％ lower than the control) after treatment with neomycin sulfate as an intracellular calcium inhibitor.Results indicate that cells regulated intracellular calcium level though Ins(1,4,5)P3 signaling pathways to response POA stress.[Conclusion] Understanding the effect of Ca2+ signal transduction pathway how P.chrysogenum responses to POA stress provides guidance for industrial penicillin production.