一个新的产黄青霉谷胱甘肽转移酶基因的克隆和鉴定

Cloning and Characterization of a Novel Glutathione Transferase Gene from Penicillium chrysogenum

摘要:

以产黄青霉（Penicillium chrysogenumv Thom）cDNA为模板，克隆得到一个新的谷胱甘肽转移酶基因PcgstB，其开放阅读框长651bp，编码216个氨基酸的蛋白质。与已知序列进行BLASTp比较显示，该蛋白具有保守的GST结构域，与烟曲霉GstB的序列一致性最高，达65%。将PcgstB与原核表达载体pTrc 99A连接得到表达质粒pTrc-gstB，转化大肠杆菌DH5α，经IPTG诱导后获得以可溶形式表达的重组PcGstB蛋白。以1-chloro-2，4-dinitrobenzene（CDNB）为底物检测，确认该蛋白具有GST活性。

Abstract:

Glutathione transferases (GSTs) are a family of multifunctional proteins that mainly catalyze the conjugation of intracellular glutathione (GSH) to a wide variety of endogenous and exogenous electrophilic compounds. GSTs play important roles in stress tolerance and in the detoxification metabolism in organisms. A novel GST gene，PcgstB，was cloned from penicillin producing fungus Penicillium chrysogenum using RT-PCR. The open reading frame (ORF) of PcgstB was 651bp and encoded a peptide of 216 residues. The deduced amino acids sequence had conserved GST domain and showed 65% identity to the characterized Aspergillus fumigutus gstB. The entire ORF of PcgstB was inserted into vector pTrc99A and transformed into Escherichia coli DH5α. Recombinant PcGstB was overexpressed and its GST activity toward substrate 1-chloro-2，4-dinitrobenzene (CDNB) was validated.