MfLIP1, a gene encoding an extracellular lipase of the lipid-dependent fungus Malassezia furfur
MfLIP1, a gene encoding an extracellular lipase of the lipid-dependent fungus Malassezia furfur
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DOI：
10.1099/mic.0.28501-0
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发表时间：
2006-02-01
期刊：
影响因子：
2.8
通讯作者：
Hube, B
中科院分区：
文献类型：
--
作者：
Brunke, S;Hube, B
糠秕马拉色菌是一种二型真菌，是人类正常皮肤微生物区系的成员。然而，它也是一种兼性病原体，与广泛的皮肤病有关。M.糠秕是对外部提供的脂质的绝对依赖，真菌通过脂解活性水解所述脂质以释放生长和致病性两者所必需的脂肪酸。本研究克隆并鉴定了第一个分泌型脂肪酶基因。报告了可能与这一活动有关的毛皮。该基因MfLIP 1与其他已知的胞外脂肪酶具有高度的序列相似性，但不是M.毛皮。MfLIP1基因全长1464 bp，编码一个分子量为54.3 kDa的蛋白质，具有保守的脂肪酶基序和26个氨基酸的N端信号肽。通过使用基因组文库，另外两个基因被确定侧翼MfLIP1，其中一个编码一个推定的分泌过氧化氢酶，另一个推定的胺氧化酶。在毕赤酵母中表达了MfLIP1基因，并对重组脂肪酶的生化特性进行了分析。MfLip1在40 ℃时最具活性，发现最适pH为5.8。脂肪酶水解的脂类，如吐温，经常被用作M. furfur媒体，并有较小的酯酶活性。此外，脂肪酶被不同的二价金属离子抑制。这是第一次从分子水平描述M.毛皮。
Malassezia furfur is a dimorphic fungus and a member of the normal cutaneous microflora of humans. However, it is also a facultative pathogen, associated with a wide range of skin diseases. One unusual feature of M. furfur is an absolute dependency on externally provided lipids which the fungus hydrolyses by lipolytic activity to release fatty acids necessary for both growth and pathogenicity. In this study, the cloning and characterization of the first gene encoding a secreted lipase of M. furfur possibly associated with this activity are reported. The gene, MfLIP1, shows high sequence similarity to other known extracellular lipases, but is not a member of a lipase gene family in M. furfur. MfLIP1 consists of 1464 bp, encoding a protein with a molecular mass of 54.3 kDa, a conserved lipase motif and an N-terminal signal peptide of 26 aa. By using a genomic library, two other genes were identified flanking MfLIP1, one of them encoding a putative secreted catalase, the other a putative amine oxidase. The cDNA of MfLIP1 was expressed in Pichia pastoris and the biochemical properties of the recombinant lipase were analysed. MfLip1 is most active at 40 degrees C and the pH optimum was found to be 5.8. The lipase hydrolysed lipids, such as Tweens, frequently used as the source of fatty acids in M. furfur media, and had minor esterase activity. Furthermore, the lipase is inhibited by different bivalent metal ions. This is the first molecular description of a secreted lipase from M. furfur.