Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, P.O. Box 15005, CEP 91501-970, Porto Alegre, RS, Brazil.
Fungal Biol. 2010 Nov-Dec;114(11-12):911-6. doi: 10.1016/j.funbio.2010.08.007. Epub 2010 Sep 17.
The filamentous fungus Metarhizium anisopliae is a well-characterized, arthropod pathogen used in the biological control of arthropod pests. Studies on the regulation of enzymes related to host infection such as proteases and chitinases have been reported but little is known about regulation of lipolytic enzymes in this fungus. Here we present the effects of different carbon sources such as components of the arthropod cuticle on the secretion of lipolytic enzymes by M. anisopliae. Differences in the induction of lipolytic activity were observed between the several carbon sources tested. Higher activities of lipase or lipase/esterase were found in culture media containing the arthropod integument components chitin and cholesteryl stearate. Several bands of lipolytic activity were also detected in zymograms, thus suggesting an important set of lipolytic enzymes secreted by the fungus. These results show that the fungus can modulate the secretion of lipolytic activity in response to host integument components, thus reinforcing the potential role of these enzymes during M. anisopliae infection.
丝状真菌绿僵菌是一种特征明确的节肢动物病原体,用于防治节肢动物害虫。已经有研究报道了与宿主感染相关的蛋白酶和几丁质酶等酶的调控,但对于该真菌中脂酶的调控知之甚少。在这里,我们介绍了不同碳源(如节肢动物外骨骼的成分)对绿僵菌脂酶分泌的影响。在所测试的几种碳源中,观察到脂解活性的诱导存在差异。在含有节肢动物外骨骼成分几丁质和胆甾醇硬脂酸的培养基中,发现了更高的脂肪酶或脂肪酶/酯酶活性。在同工酶图谱中还检测到了几条脂解活性带,因此表明真菌分泌了一组重要的脂酶。这些结果表明,真菌可以根据宿主外骨骼成分来调节脂解活性的分泌,从而强化这些酶在绿僵菌感染过程中的潜在作用。