Kim Hong-Il, Kwon O-Chul, Kong Won-Sik, Lee Chang-Soo, Park Young-Jin
Department of Biomedical Chemistry, Konkuk University, Chungju 380-701, Korea.
Mushroom Research Division, National Institute of Horticultural and Herbal Science, Rural Development Administration, Suwon 440-706, Korea.
Mycobiology. 2014 Dec;42(4):322-30. doi: 10.5941/MYCO.2014.42.4.322. Epub 2014 Dec 31.
The aim of this study was to identify and characterize new Flammulina velutipes laccases from its whole-genome sequence. Of the 15 putative laccase genes detected in the F. velutipes genome, four new laccase genes (fvLac-1, fvLac-2, fvLac3, and fvLac-4) were found to contain four complete copper-binding regions (ten histidine residues and one cysteine residue) and four cysteine residues involved in forming disulfide bridges, fvLac-1, fvLac-2, fvLac3, and fvLac-4, encoding proteins consisting of 516, 518, 515, and 533 amino acid residues, respectively. Potential N-glycosylation sites (Asn-Xaa-Ser/Thr) were identified in the cDNA sequence of fvLac-1 (Asn-454), fvLac-2 (Asn-437 and Asn-455), fvLac-3 (Asn-111 and Asn-237), and fvLac4 (Asn-402 and Asn-457). In addition, the first 19~20 amino acid residues of these proteins were predicted to comprise signal peptides. Laccase activity assays and reverse transcription polymerase chain reaction analyses clearly reveal that CuSO4 affects the induction and the transcription level of these laccase genes.
本研究的目的是从金针菇全基因组序列中鉴定并表征新的漆酶。在金针菇基因组中检测到的15个假定漆酶基因中,发现四个新的漆酶基因(fvLac-1、fvLac-2、fvLac3和fvLac-4)包含四个完整的铜结合区域(十个组氨酸残基和一个半胱氨酸残基)以及四个参与形成二硫键的半胱氨酸残基,fvLac-1、fvLac-2、fvLac3和fvLac-4分别编码由516、518、515和533个氨基酸残基组成的蛋白质。在fvLac-1(Asn-454)、fvLac-2(Asn-437和Asn-455)、fvLac-3(Asn-111和Asn-237)和fvLac4(Asn-402和Asn-457)的cDNA序列中鉴定出潜在的N-糖基化位点(Asn-Xaa-Ser/Thr)。此外,预测这些蛋白质的前19至20个氨基酸残基包含信号肽。漆酶活性测定和逆转录聚合酶链反应分析清楚地表明,硫酸铜会影响这些漆酶基因的诱导和转录水平。