Saline-dependent regulation of manganese peroxidase genes in the hypersaline-tolerant white rot fungus Phlebia sp strain MG-60
Saline-dependent regulation of manganese peroxidase genes in the hypersaline-tolerant white rot fungus Phlebia sp strain MG-60
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DOI：
10.1128/aem.02257-07
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发表时间：
2008-05-01
影响因子：
4.4
通讯作者：
Kondo, Ryuichiro
中科院分区：
文献类型：
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作者：
Kamei, Ichiro;Daikoku, Chieko;Kondo, Ryuichiro
耐盐真菌Phlebia sp.菌株MG-60氮限制培养物中锰过氧化物酶（MnPs）的表达模式在高盐条件下在mRNA水平上受到差异调节。MG-60在含3% （wt/vol）海盐（LN-SSM）的限氮培养基（LNM）中培养时，MnPs活性高于正常培养基（LNM）。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析表明，两种MnP同工酶在LN-SSM培养中重新合成。采用逆转录(RT)-PCR和cDNA末端快速扩增技术分离MGmnp1、MGmnp2和MGmnp3 3个mnp编码基因。通过肽质量指纹图谱分析鉴定了相应的同工酶。MGmnp2和MGmnp3编码的MnP同工酶主要存在于LN-SSM中。Real-time RT-PCR分析显示，添加2% NaCl后48 h， LN-SSM中MGmnp2和MGmnp3转录物水平较高。在Mn2+存在的情况下，生理盐水诱导MnP的产生与基因转录物的积累具有良好的相关性。然而，在缺乏Mn2+的情况下，mnp转录物水平与mnp活性之间没有明显的相关性，这表明Mn2+参与了转录后调控。
The expression pattern of manganese peroxidases (MnPs) in nitrogen-limited cultures of the saline-tolerant fungus Phlebia sp. strain MG-60 is differentially regulated under hypersaline conditions at the mRNA level. When MG-60 was cultured in nitrogen-limited medium (LNM) containing 3% (wt/vol) sea salts (LN-SSM), higher activity of MnPs was observed than that observed in normal medium (LNM). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis demonstrated that two MnP isoenzymes were de novo synthesized in the culture of LN-SSM. Three MnP-encoding genes (MGmnp1, MGmnp2, and MGmnp3) were isolated by reverse transcription (RT)-PCR and rapid amplification of cDNA ends PCR techniques. The corresponding isozymes were identified by peptide mass fingerprinting analysis. MnP isozymes encoded by MGmnp2 and MGmnp3 were observed mainly in LN-SSM. Real-time RT-PCR analysis revealed high levels of MGmnp2 and MGmnp3 transcripts in LN-SSM 48 h after the addition of 2% NaCl. The induction of MnP production and the accumulation of gene transcripts by saline were well correlated in the presence of Mn2+. However, in the absence of Mn2+, there was no clear correlation between mnp transcripts levels and MnP activity, suggesting posttranscriptional regulation by Mn2+.