Montesano Marcos, Hyytiäinen Heidi, Wettstein Rodolfo, Palva E Tapio
Department of Biosciences, Division of Genetics, University of Helsinki, Box 56, 00014 Finland.
Plant Mol Biol. 2003 May;52(1):177-89. doi: 10.1023/a:1023981631596.
Identification of Solanum tuberosum genes responsive to culture filtrates (CF) from Erwinia carotovora subsp. carotovora led to the isolation of a full-length cDNA with high sequence similarity to several alcohol dehydrogenases. Accumulation of transcripts corresponding to this defence-related alcohol dehydrogenase (drd-1) was rapidly induced in CF-treated and wounded plants. The gene was also responsive to molecules involved in defence signalling such as salicylic acid, methyl jasmonate and ethylene. To elucidate the biochemical function of DRD-1, its cDNA was expressed in Escherichia coli. Enzymatic assays revealed that DRD-1 is an alcohol:NADP+ oxidoreductase with preference for various aromatic and aliphatic aldehydes. The enzyme exhibited high activity with several aldehydes including 2-methoxybenzaldehyde, 3-methoxybenzaldehyde, salicylaldehyde, o-vanillin, cinnamaldehyde, hydrocinnamaldehyde, hexanal and octanal. Identification of the reaction product by thin-layer chromatography confirmed the reduction of aldehydes to alcohols. Enzymatic activity measured with 2-methoxybenzaldehyde as a substrate was increased in salicylic acid- or methyl jasmonate-treated plants. These data suggest that DRD-1 may play an important role in potato defence response to Erwinia carotovora.
对来自胡萝卜软腐欧文氏菌胡萝卜软腐亚种的培养滤液（CF）有响应的马铃薯基因的鉴定，导致分离出一个与几种乙醇脱氢酶具有高度序列相似性的全长cDNA。在CF处理和受伤的植物中，与这种防御相关的乙醇脱氢酶（drd-1）对应的转录本积累迅速被诱导。该基因对参与防御信号传导的分子如水杨酸、茉莉酸甲酯和乙烯也有响应。为了阐明DRD-1的生化功能，其cDNA在大肠杆菌中表达。酶活性测定表明，DRD-1是一种乙醇：NADP +氧化还原酶，对各种芳香族和脂肪族醛有偏好。该酶对包括2-甲氧基苯甲醛、3-甲氧基苯甲醛、水杨醛、邻香草醛、肉桂醛、氢化肉桂醛、己醛和辛醛在内的几种醛表现出高活性。通过薄层色谱法鉴定反应产物证实了醛被还原为醇。以2-甲氧基苯甲醛为底物测定的酶活性在水杨酸或茉莉酸甲酯处理的植物中增加。这些数据表明，DRD-1可能在马铃薯对胡萝卜软腐欧文氏菌的防御反应中起重要作用。
