title: Lipase genes in Mucor circinelloides: identification, sub-cellular location, phylogenetic analysis and expression profiling during growth and lipid accumulation.
abstract: Lipases or triacylglycerol hydrolases are widely spread in nature and are particularly common in the microbial world. The filamentous fungus Mucor circinelloides is a potential lipase producer, as it grows well in triacylglycerol-contained culture media. So far only one lipase from M. circinelloides has been characterized, while the majority of lipases remain unknown in this fungus. In the present study, 47 potential lipase genes in M. circinelloides WJ11 and 30 potential lipase genes in M. circinelloides CBS 277.49 were identified by extensive bioinformatics analysis. An overview of these lipases is presented, including several characteristics, sub-cellular location, phylogenetic analysis and expression profiling of the lipase genes during growth and lipid accumulation. All of these proteins contained the consensus sequence for a classical lipase (GXSXG motif) and were divided into four types including α/β-hydrolase_1, α/β-hydrolase_3, class_3 and GDSL lipase (GDSL) based on gene annotations. Phylogenetic analyses revealed that class_3 family and α/β-hydrolase_3 family were the conserved lipase family in M. circinelloides. Additionally, some lipases also contained a typical acyltransferase motif of H-(X) 4-D, and these lipases may play a dual role in lipid metabolism, catalyzing both lipid hydrolysis and transacylation reactions. The differential expression of all lipase genes were confirmed by quantitative real-time PCR, and the expression profiling were analyzed to predict the possible biological roles of these lipase genes in lipid metabolism in M. circinelloides. We preliminarily hypothesized that lipases may be involved in triacylglycerol degradation, phospholipid synthesis and beta-oxidation. Moreover, the results of sub-cellular localization, the presence of signal peptide and transcriptional analyses of lipase genes indicated that four lipase in WJ11 most likely belong to extracellular lipases with a signal peptide. These findings provide a platform for the selection of candidate lipase genes for further detailed functional study.
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Zan
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
authors.forename: Linfang
authors.initials: L
authors.lastname: Chu
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
authors.forename: Lina
authors.initials: L
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.|Synergistic Innovation Center for Food Safety and Nutrition, Wuxi, People's Republic of China.
authors.forename: Haiqin
authors.initials: H
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.|Synergistic Innovation Center for Food Safety and Nutrition, Wuxi, People's Republic of China.
authors.forename: Yong Q
authors.initials: YQ
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.|Synergistic Innovation Center for Food Safety and Nutrition, Wuxi, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China. ysong@jiangnan.edu.cn.|Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo, People's Republic of China. ysong@jiangnan.edu.cn.
authors.forename: Yuanda
authors.initials: Y
authors.lastname: Song
mesh_terms: D020816:Amino Acid Motifs; D019295:Computational Biology; D016384:Consensus Sequence; D020869:Gene Expression Profiling; D008049:Lipase / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D050356:Lipid Metabolism / Q000235:genetics; D009089:Mucor / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism; D010802:Phylogeny; D021382:Protein Sorting Signals
chemical_list: D021382:Protein Sorting Signals; D008049:Lipase