Zhang H M, Wu M C, Guo J, Li J F
School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China.
Prikl Biokhim Mikrobiol. 2011 Nov-Dec;47(6):642-9.
The complete gene (PG37 lipI) encoding an alkaline lipase (PG37 LipI) was cloned from the genomic DNA of Penicillium cyclopium PG37. The cloned PG37 lipI is 2020 bp in length, consisting of 632 bp of the 5' flanking promoter region and 1388 bp of the downstream fragment that contains 6 exons and 5 short introns. The promoter region harbors putative TATA box, CAAT box and several transcription factor binding sites. The open reading frame (ORF) encodes a PG37 LipI of 285 amino acid residues, which was predicted to contain a 20-aa signal peptide, a 7-aa propeptide and a 258-aa mature peptide with a conserved motif Gly-X-Ser-X-Gly. However, PG37 LipI shows only 32%, 30%, 28% and 26% identity with lipases of Aspergillus parasiticus, Penicillium camembertii, Thermomyces lanuginosus and Rhizomucor miehei, respectively. It was predicted that the main secondary structures of PG37 LipI are alpha-helix and random coil. Three amino acid residues, Ser132-Asp188-His241, compose the enzymatic active center in the tertiary structure.
从环孢青霉PG37的基因组DNA中克隆出编码碱性脂肪酶（PG37 LipI）的完整基因（PG37 lipI）。克隆得到的PG37 lipI长度为2020 bp，由5'侧翼启动子区域的632 bp和包含6个外显子及5个短内含子的下游片段的1388 bp组成。启动子区域含有推定的TATA框、CAAT框和几个转录因子结合位点。开放阅读框（ORF）编码一个含285个氨基酸残基的PG37 LipI，预计其包含一个20个氨基酸的信号肽、一个7个氨基酸的前肽和一个含保守基序Gly-X-Ser-X-Gly的258个氨基酸的成熟肽。然而，PG37 LipI与寄生曲霉、卡门柏青霉、疏棉状嗜热丝孢菌和米黑根毛霉的脂肪酶的一致性分别仅为32%、30%、28%和26%。据预测，PG37 LipI的主要二级结构为α-螺旋和无规卷曲。三个氨基酸残基Ser132-Asp188-His241在三级结构中构成酶活性中心。
