Fonsecaea monophora黑素的理化性质及其合成途径的分析研究

摘要

Objective To study the melanin physiochemical characterization and melanin synthesis pathway of Fonsecaea monophora.Methods Pure melanin mass was extracted from the F.monophora isolate using the cell wall crude extract method.Then we used Ultravolet (Uv),Fourier transformed infrared (FT-IR) and electron paramagnetic resonance (EPR) spectra assay to evaluate the physiochemical characterization of melanin.Furthermore,we observed the pigment production of the colonies on different mediums (PDA,PDA with L-DOPA,PDA with DOPA-melanin inhibitors and PDA with DHN-melanin inhibitors),and the quantity of melanin produced on different above media were measured using BioTek Eon microplate reader.Results The melanin extracted from F.monophora shared similar physiochemical and spectroscopic properties with the synthetic L-DOPA melanin.The formation of melanin pigment statistically significant increased on the L-DOPA medium,and decreased on the DOPA-melanin inhibitor medium (sodium azide) and DHN-melanin inhibitors medium (phthalide and tricyclazole) compare to their blank contrast medium.Conclusions The melanin produced by F.monophora is mainly DOPA melanin,and it may synthesize simultaneously by DOPA-melanin and DHN-melanin pathway.%目的 探讨Fonsecaea monophora黑素的理化性质及其合成途径.方法 通过化学分析、紫外光谱、红外光谱和电子顺磁共振波谱等明确F.monophora黑素的理化性质;通过比对F.monophora菌株在基础培养基(马铃薯葡萄糖琼脂(PDA)培养基、L-DOPA PDA培养基)和含黑素抑制剂培养基(DOPA黑素抑制剂培养基、DHN黑素抑制剂培养基)的菌落生长情况,采用BioTek酶标仪EON定量分析其黑素合成,以明确F.monophora的黑素合成途径.结果 F.monophora黑素与合成L-DOPA黑素的理化性质相似;菌株在含L-DOPA培养基较PDA培养基产生更多的黑素,且在含DOPA黑素抑制剂叠氮化钠及DHN黑素抑制剂苯肽、三环唑培养基中其黑素合成均明显降低.结论 F.monophora黑素主要为L-DOPA黑素,可能共同存在DOPA黑素和DHN黑素合成途径.