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Jensen SJ, Ruhe ZC, Williams AF, Nhan DQ, Garza-Sánchez F, Low DA, Hayes CS. Paradoxical Activation of a Type VI Secretion System Phospholipase Effector by Its Cognate Immunity Protein. J Bacteriol 2023; 205:e0011323. [PMID: 37212679 PMCID: PMC10294671 DOI: 10.1128/jb.00113-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/03/2023] [Indexed: 05/23/2023] Open
Abstract
Type VI secretion systems (T6SSs) deliver cytotoxic effector proteins into target bacteria and eukaryotic host cells. Antibacterial effectors are invariably encoded with cognate immunity proteins that protect the producing cell from self-intoxication. Here, we identify transposon insertions that disrupt the tli immunity gene of Enterobacter cloacae and induce autopermeabilization through unopposed activity of the Tle phospholipase effector. This hyperpermeability phenotype is T6SS dependent, indicating that the mutants are intoxicated by Tle delivered from neighboring sibling cells rather than by internally produced phospholipase. Unexpectedly, an in-frame deletion of tli does not induce hyperpermeability because Δtli null mutants fail to deploy active Tle. Instead, the most striking phenotypes are associated with disruption of the tli lipoprotein signal sequence, which prevents immunity protein localization to the periplasm. Immunoblotting reveals that most hyperpermeable mutants still produce Tli, presumably from alternative translation initiation codons downstream of the signal sequence. These observations suggest that cytosolic Tli is required for the activation and/or export of Tle. We show that Tle growth inhibition activity remains Tli dependent when phospholipase delivery into target bacteria is ensured through fusion to the VgrG β-spike protein. Together, these findings indicate that Tli has distinct functions, depending on its subcellular localization. Periplasmic Tli acts as a canonical immunity factor to neutralize incoming effector proteins, while a cytosolic pool of Tli is required to activate the phospholipase domain of Tle prior to T6SS-dependent export. IMPORTANCE Gram-negative bacteria use type VI secretion systems deliver toxic effector proteins directly into neighboring competitors. Secreting cells also produce specific immunity proteins that neutralize effector activities to prevent autointoxication. Here, we show the Tli immunity protein of Enterobacter cloacae has two distinct functions, depending on its subcellular localization. Periplasmic Tli acts as a canonical immunity factor to block Tle lipase effector activity, while cytoplasmic Tli is required to activate the lipase prior to export. These results indicate Tle interacts transiently with its cognate immunity protein to promote effector protein folding and/or packaging into the secretion apparatus.
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Affiliation(s)
- Steven J. Jensen
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, USA
| | - Zachary C. Ruhe
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, USA
| | - August F. Williams
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, USA
| | - Dinh Q. Nhan
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, USA
| | - Fernando Garza-Sánchez
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, USA
| | - David A. Low
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, USA
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, Santa Barbara, California, USA
| | - Christopher S. Hayes
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, USA
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, Santa Barbara, California, USA
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2
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Jensen SJ, Ruhe ZC, Williams AF, Nhan DQ, Garza-Sánchez F, Low DA, Hayes CS. Paradoxical activation of a type VI secretion system (T6SS) phospholipase effector by its cognate immunity protein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.28.534661. [PMID: 37034769 PMCID: PMC10081291 DOI: 10.1101/2023.03.28.534661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Type VI secretion systems (T6SS) deliver cytotoxic effector proteins into target bacteria and eukaryotic host cells. Antibacterial effectors are invariably encoded with cognate immunity proteins that protect the producing cell from self-intoxication. Here, we identify transposon insertions that disrupt the tli immunity gene of Enterobacter cloacae and induce auto-permeabilization through unopposed activity of the Tle phospholipase effector. This hyper-permeability phenotype is T6SS-dependent, indicating that the mutants are intoxicated by Tle delivered from neighboring sibling cells rather than by internally produced phospholipase. Unexpectedly, an in-frame deletion of tli does not induce hyper-permeability because Δ tli null mutants fail to deploy active Tle. Instead, the most striking phenotypes are associated with disruption of the tli lipoprotein signal sequence, which prevents immunity protein localization to the periplasm. Immunoblotting reveals that most hyper-permeable mutants still produce Tli, presumably from alternative translation initiation codons downstream of the signal sequence. These observations suggest that cytosolic Tli is required for the activation and/or export of Tle. We show that Tle growth inhibition activity remains Tli-dependent when phospholipase delivery into target bacteria is ensured through fusion to the VgrG β-spike protein. Together, these findings indicate that Tli has distinct functions depending on its subcellular localization. Periplasmic Tli acts as a canonical immunity factor to neutralize incoming effector proteins, while a cytosolic pool of Tli is required to activate the phospholipase domain of Tle prior to T6SS-dependent export.
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3
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Lee J, Kim NH, Choi Y, Yang E, Yu H, Kwon CW, Chang PS. Divergent substrate specificities and regioselectivities of three lipase isoforms from Cordyceps militaris: Combinatorial advantages for entomopathogenicity and prospects as biocatalysts. Enzyme Microb Technol 2022; 161:110117. [PMID: 36049397 DOI: 10.1016/j.enzmictec.2022.110117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 07/19/2022] [Accepted: 08/23/2022] [Indexed: 11/18/2022]
Abstract
Cordyceps militaris, an entomopathogenic Cordyceps mushroom, is a crucial ethnopharmacological agricultural product with applications in traditional oriental remedies in East Asia. Since lipases are reported to serve as key enzymatic equipment for entomopathogenic fungi during the host infection, the presence of various lipases with different biochemical features in C. militaris was elucidated. Three lipases from C. militaris (CML) of 60-70 kDa were isolated according to protein hydrophobicity; isoform relationships were identified by peptide mapping using liquid chromatography-electrospray ionization-tandem mass spectrometry. The CML isoforms exhibited distinct substrate specificities, which were related to the hydrophobicity of each isoform. Furthermore, the integral stereoselectivity of each lipase towards trioleoylglycerol diverged into two classes (sn-1,3 and sn-2 regioselectivity) that are rare in canonical fungal lipases. Overall, our results demonstrate that C. militaris secretes lipase isoforms with cocktail-like enzyme functions that may contribute to the entomopathogenic life cycle of C. militaris. Each CML isoform has distinct advantages for biocatalyst applications in the food and oleochemical industries.
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Affiliation(s)
- Juno Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea
| | - Nam-Hyun Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea
| | - Yoonseok Choi
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea
| | - Eunhye Yang
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea
| | - Hyunjong Yu
- Center for Agricultural Microorganism and Enzyme, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Chang Woo Kwon
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Pahn-Shick Chang
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 08826, Republic of Korea; Center for Agricultural Microorganism and Enzyme, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea.
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Effectors of the Stenotrophomonas maltophilia Type IV Secretion System Mediate Killing of Clinical Isolates of Pseudomonas aeruginosa. mBio 2021; 12:e0150221. [PMID: 34182776 PMCID: PMC8262851 DOI: 10.1128/mbio.01502-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Previously, we documented that Stenotrophomonas maltophilia encodes a type IV secretion system (T4SS) that allows the organism to kill, in contact-dependent fashion, heterologous bacteria, including wild-type Pseudomonas aeruginosa. Bioinformatic screens based largely on the presence of both a C-terminal consensus sequence and an adjacent gene encoding a cognate immunity protein identified 13 potential antibacterial effectors, most of which were highly conserved among sequenced strains of S. maltophilia. The immunity proteins of two of these proved especially capable of protecting P. aeruginosa and Escherichia coli against attack from the Stenotrophomonas T4SS. In turn, S. maltophilia mutants lacking the putative effectors RS14245 and RS14255 were impaired for killing not only laboratory E. coli but clinical isolates of P. aeruginosa, including ones isolated from the lungs of cystic fibrosis patients. That complemented mutants behaved as wild type did confirmed that RS14245 and RS14255 are required for the bactericidal activity of the S. maltophilia T4SS. Moreover, a mutant lacking both of these proteins was as impaired as a mutant lacking the T4SS apparatus, indicating that RS14245 and RS14255 account for (nearly) all of the bactericidal effects seen. Utilizing an interbacterial protein translocation assay, we determined that RS14245 and RS14255 are bona fide substrates of the T4SS, a result confirmed by examination of mutants lacking both the T4SS and the individual effectors. Delivery of the cloned 14245 protein (alone) into the periplasm resulted in the killing of target bacteria, indicating that this effector, a putative lipase, is both necessary and sufficient for bactericidal activity.
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5
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Xing S, Zhu R, Cheng K, Cai Y, Hu Y, Li C, Zeng X, Zhu Q, He L. Gene Expression, Biochemical Characterization of a sn-1, 3 Extracellular Lipase From Aspergillus niger GZUF36 and Its Model-Structure Analysis. Front Microbiol 2021; 12:633489. [PMID: 33776965 PMCID: PMC7994357 DOI: 10.3389/fmicb.2021.633489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 02/22/2021] [Indexed: 11/13/2022] Open
Abstract
In this study, a sn-1, 3 extracellular lipases from Aspergillus niger GZUF36 (PEXANL1) was expressed in Pichia pastoris, characterized, and the predicted structural model was analyzed. The optimized culture conditions of P. pastoris showed that the highest lipase activity of 66.5 ± 1.4 U/mL (P < 0.05) could be attained with 1% methanol and 96 h induction time. The purified PEXANL1 exhibited the highest activity at pH 4.0 and 40°C temperature, and its original activity remained unaltered in the majority of the organic solvents (20% v/v concentration). Triton X-100, Tween 20, Tween 80, and SDS at a concentration of 0.01% (w/v) enhanced, and all the metal ions tested inhibited activity of purified PEXANL. The results of ultrasound-assisted PEXANL1 catalyzed synthesis of 1,3-diaglycerides showed that the content of 1,3-diglycerides was rapidly increased to 36.90% with 25 min of ultrasound duration (P < 0.05) and later decreased to 19.93% with 35 min of ultrasound duration. The modeled structure of PEXANL1 by comparative modeling showed α/β hydrolase fold. Structural superposition and molecular docking results validated that Ser162, His274, and Asp217 residues of PEXANL1 were involved in the catalysis. Small-angle X-ray scattering analysis indicated the monomer properties of PEXANL1 in solution. The ab initio model of PEXANL1 overlapped with its modeling structure. This work presents a reliable structural model of A. niger lipase based on homology modeling and small-angle X-ray scattering. Besides, the data from this study will benefit the rational design of suitable crystalline lipase variants in the future.
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Affiliation(s)
- Shuqi Xing
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
| | - Ruonan Zhu
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
| | - Kai Cheng
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
| | - Yangyang Cai
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
| | - Yuedan Hu
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
| | - Cuiqin Li
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
- School of Chemistry and Chemical Engineering, Guizhou University, Guiyang, China
- Guizhou Province Key Laboratory of Fermentation Engineering and Biopharmacy, Guizhou University, Guiyang, China
| | - Xuefeng Zeng
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
- Guizhou Province Key Laboratory of Fermentation Engineering and Biopharmacy, Guizhou University, Guiyang, China
| | - Qiujin Zhu
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
- Guizhou Province Key Laboratory of Fermentation Engineering and Biopharmacy, Guizhou University, Guiyang, China
| | - Laping He
- Key Laboratory of Agricultural and Animal Products Store and Processing of Guizhou Province, Guizhou University, Guiyang, China
- College of Liquor and Food Engineering, Guizhou University, Guiyang, China
- Guizhou Province Key Laboratory of Fermentation Engineering and Biopharmacy, Guizhou University, Guiyang, China
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Verma S, Meghwanshi GK, Kumar R. Current perspectives for microbial lipases from extremophiles and metagenomics. Biochimie 2021; 182:23-36. [PMID: 33421499 DOI: 10.1016/j.biochi.2020.12.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 12/21/2020] [Accepted: 12/31/2020] [Indexed: 01/21/2023]
Abstract
Microbial lipases are most broadly used biocatalysts for environmental and industrial applications. Lipases catalyze the hydrolysis and synthesis of long acyl chain esters and have a characteristic folding pattern of α/β hydrolase with highly conserved catalytic triad (Serine, Aspartic/Glutamic acid and Histidine). Mesophilic lipases (optimal activity in neutral pH range, mesophilic temperature range, atmospheric pressure, normal salinity, non-radio-resistant, and instability in organic solvents) have been in use for many industrial biotransformation reactions. However, lipases from extremophiles can be used to design biotransformation reactions with higher yields, less byproducts or useful side products and have been predicted to catalyze those reactions also, which otherwise are not possible with the mesophilic lipases. The extremophile lipase perform activity at extremes of temperature, pH, salinity, and pressure which can be screened from metagenome and de novo lipase design using computational approaches. Despite structural similarity, they exhibit great diversity at the sequence level. This diversity is broader when lipases from the bacterial, archaeal, plant, and animal domains/kingdoms are compared. Furthermore, a great diversity of novel lipases exists and can be discovered from the analysis of the dark matter - the unexplored nucleotide/metagenomic databases. This review is an update on extremophilic microbial lipases, their diversity, structure, and classification. An overview on novel lipases which have been detected through analysis of the genomic dark matter (metagenome) has also been presented.
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Affiliation(s)
- Swati Verma
- Department of Microbiology, Maharaja Ganga Singh University, Bikaner, 334004, India
| | | | - Rajender Kumar
- Department of Clinical Microbiology, Umeå University, SE-90185, Umeå, Sweden.
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Sahaka M, Amara S, Wattanakul J, Gedi MA, Aldai N, Parsiegla G, Lecomte J, Christeller JT, Gray D, Gontero B, Villeneuve P, Carrière F. The digestion of galactolipids and its ubiquitous function in Nature for the uptake of the essential α-linolenic acid. Food Funct 2020; 11:6710-6744. [PMID: 32687132 DOI: 10.1039/d0fo01040e] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Galactolipids, mainly monogalactosyl diglycerides and digalactosyl diglycerides are the main lipids found in the membranes of plants, algae and photosynthetic microorganisms like microalgae and cyanobacteria. As such, they are the main lipids present at the surface of earth. They may represent up to 80% of the fatty acid stocks, including a large proportion of polyunsaturated fatty acids mainly α-linolenic acid (ALA). Nevertheless, the interest in these lipids for nutrition and other applications remains overlooked, probably because they are dispersed in the biomass and are not as easy to extract as vegetable oils from oleaginous fruit and oil seeds. Another reason is that galactolipids only represent a small fraction of the acylglycerolipids present in modern human diet. In herbivores such as horses, fish and folivorous insects, galactolipids may however represent the main source of dietary fatty acids due to their dietary habits and digestion physiology. The development of galactolipase assays has led to the identification and characterization of the enzymes involved in the digestion of galactolipids in the gastrointestinal tract, as well as by microorganisms. Pancreatic lipase-related protein 2 (PLRP2) has been identified as an important factor of galactolipid digestion in humans, together with pancreatic carboxyl ester hydrolase (CEH). The levels of PLRP2 are particularly high in monogastric herbivores thus highlighting the peculiar role of PLRP2 in the digestion of plant lipids. Similarly, pancreatic lipase homologs are found to be expressed in the midgut of folivorous insects, in which a high galactolipase activity can be measured. In fish, however, CEH is the main galactolipase involved. This review discusses the origins and fatty acid composition of galactolipids and the physiological contribution of galactolipid digestion in various species. This overlooked aspect of lipid digestion ensures not only the intake of ALA from its main natural source, but also the main lipid source of energy for growth of some herbivorous species.
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Affiliation(s)
- Moulay Sahaka
- Aix Marseille Univ, CNRS, UMR7281 Bioénergétique et Ingénierie des Protéines, 31 Chemin Joseph Aiguier, 13009 Marseille, France.
| | - Sawsan Amara
- Lipolytech, Zone Luminy Biotech, 163 avenue de Luminy, 13288 Marseille Cedex 09, France
| | - Jutarat Wattanakul
- Division of Food, Nutrition and Dietetics, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK
| | - Mohamed A Gedi
- Division of Food, Nutrition and Dietetics, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK
| | - Noelia Aldai
- Lactiker Research Group, Department of Pharmacy & Food Sciences, University of the Basque Country (UPV/EHU), 01006 Vitoria-Gasteiz, Spain
| | - Goetz Parsiegla
- Aix Marseille Univ, CNRS, UMR7281 Bioénergétique et Ingénierie des Protéines, 31 Chemin Joseph Aiguier, 13009 Marseille, France.
| | | | - John T Christeller
- The New Zealand Institute for Plant and Food Research Ltd (Plant & Food Research), Palmerston North Research Centre, Palmerston North, New Zealand
| | - David Gray
- Division of Food, Nutrition and Dietetics, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK
| | - Brigitte Gontero
- Aix Marseille Univ, CNRS, UMR7281 Bioénergétique et Ingénierie des Protéines, 31 Chemin Joseph Aiguier, 13009 Marseille, France.
| | | | - Frédéric Carrière
- Aix Marseille Univ, CNRS, UMR7281 Bioénergétique et Ingénierie des Protéines, 31 Chemin Joseph Aiguier, 13009 Marseille, France.
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Zhang M, Yu XW, Xu Y, Guo RT, Swapna GVT, Szyperski T, Hunt JF, Montelione GT. Structural Basis by Which the N-Terminal Polypeptide Segment of Rhizopus chinensis Lipase Regulates Its Substrate Binding Affinity. Biochemistry 2019; 58:3943-3954. [PMID: 31436959 PMCID: PMC7195698 DOI: 10.1021/acs.biochem.9b00462] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Members of an important group of industrial enzymes, Rhizopus lipases, exhibit valuable hydrolytic features that underlie their biological functions. Particularly important is their N-terminal polypeptide segment (NTPS), which is required for secretion and proper folding but is removed in the process of enzyme maturation. A second common feature of this class of lipases is the α-helical "lid", which regulates the accessibility of the substrate to the enzyme active site. Some Rhizopus lipases also exhibit "interfacial activation" by micelle and/or aggregate surfaces. While it has long been recognized that the NTPS is critical for function, its dynamic features have frustrated efforts to characterize its structure by X-ray crystallography. Here, we combine nuclear magnetic resonance spectroscopy and X-ray crystallography to determine the structure and dynamics of Rhizopus chinensis lipase (RCL) with its 27-residue NTPS prosequence (r27RCL). Both r27RCL and the truncated mature form of RCL (mRCL) exhibit biphasic interfacial activation kinetics with p-nitrophenyl butyrate (pNPB). r27RCL exhibits a substrate binding affinity significantly lower than that of mRCL due to stabilization of the closed lid conformation by the NTPS. In contrast to previous predictions, the NTPS does not enhance lipase activity by increasing surface hydrophobicity but rather inhibits activity by forming conserved interactions with both the closed lid and the core protein structure. Single-site mutations and kinetic studies were used to confirm that the NTPS serves as internal competitive inhibitor and to develop a model of the associated process of interfacial activation. These structure-function studies provide the basis for engineering RCL lipases with enhanced catalytic activities.
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Affiliation(s)
- Meng Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
| | - Xiao-Wei Yu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
| | - Yan Xu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
| | - Rey-Ting Guo
- Industrial Enzyme National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, People’s Republic of China
| | - G. V. T. Swapna
- Center for Advanced Biotechnology and Medicine, and Department of Molecular Biology and Biochemistry, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854, USA
| | - Thomas Szyperski
- Department of Chemistry, State University of New York at Buffalo, Buffalo, New York, 14260. USA
| | - John F. Hunt
- Department of Biological Science, Columbia University, New York, New York 10027, USA
| | - Gaetano T. Montelione
- Center for Advanced Biotechnology and Medicine, and Department of Molecular Biology and Biochemistry, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854, USA
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854, USA
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9
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Wang F, Chen W, Abousalham A, Yang B, Wang Y. Exploring the influence of phospholipid monolayer conformation and environmental conditions on the interfacial binding of Gibberella Zeae lipase. Int J Biol Macromol 2019; 132:1051-1056. [PMID: 30922913 DOI: 10.1016/j.ijbiomac.2019.03.169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 03/22/2019] [Accepted: 03/25/2019] [Indexed: 10/27/2022]
Abstract
The involvement of different parameters on Gibberella zeae lipase (GZEL) membrane binding were characterized by using monomolecular film technology and circular dichroism spectroscopy. Among four kinds of phospholipid monolayers, 1,2‑dimyristoyl‑sn‑glycero‑3‑phosphoethanolamine have the highest maximum insertion pressure (MIP) value. Comparing the GZEL adsorption to phosphatidylcholine monolayers with different acyl chains in sn-1 and sn-2 positions, the higher MIP values were found for 1,2‑dilauroyl‑sn‑glycero‑3‑phosphocholine. Significantly improvement between 1,2‑dioleoyl‑sn‑glycero‑3‑phosphocholine and 1,2‑distearoyl‑sn‑glycero‑3‑phosphocholine suggested that the presence of fatty acid unsaturation may affect protein adsorption by changing the chemical structure in each phospholipid. The MIP value was shown higher (48.6 mN m-1) at pH 5 and pH 6 (47.5 ± 1.9 mN m-1) but decreased significantly (34.2 mN m-1) at pH 9. This may indicate that the proportion of helices in the protein decreases with the alteration of the catalytic center, thus affecting the binding of the protein to its substrate. The MIP values obviously decreased with increasing salt ion concentration, suggesting that excessive salt ion concentration may destabilize the secondary and tertiary structures of the protein, thereby affecting the characteristics of its adsorption at the interfaces. Present studies improve our understanding on the protein-membrane interaction of this enzyme.
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Affiliation(s)
- Fanghua Wang
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Wuchong Chen
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Abdelkarim Abousalham
- Univ Lyon, Université Lyon 1, Institut de Chimie et de Biochimie Moléculaires et Supramoléculaires (ICBMS), UMR 5246 CNRS, Métabolisme, Enzymes et Mécanismes Moléculaires (MEM(2)), Bât Raulin, 43 Bd du 11 Novembre 1918, F-69622 Villeurbanne CEDEX, France
| | - Bo Yang
- School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, China
| | - Yonghua Wang
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
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10
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Moroz OV, Blagova E, Reiser V, Saikia R, Dalal S, Jørgensen CI, Bhatia VK, Baunsgaard L, Andersen B, Svendsen A, Wilson KS. Novel Inhibitory Function of the Rhizomucor miehei Lipase Propeptide and Three-Dimensional Structures of Its Complexes with the Enzyme. ACS OMEGA 2019; 4:9964-9975. [PMID: 31460089 PMCID: PMC6648591 DOI: 10.1021/acsomega.9b00612] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 05/13/2019] [Indexed: 06/10/2023]
Abstract
Many proteins are synthesized as precursors, with propeptides playing a variety of roles such as assisting in folding or preventing them from being active within the cell. While the precise role of the propeptide in fungal lipases is not completely understood, it was previously reported that mutations in the propeptide region of the Rhizomucor miehei lipase have an influence on the activity of the mature enzyme, stressing the importance of the amino acid composition of this region. We here report two structures of this enzyme in complex with its propeptide, which suggests that the latter plays a role in the correct maturation of the enzyme. Most importantly, we demonstrate that the propeptide shows inhibition of lipase activity in standard lipase assays and propose that an important role of the propeptide is to ensure that the enzyme is not active during its expression pathway in the original host.
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Affiliation(s)
- Olga V. Moroz
- York
Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, U.K.
| | - Elena Blagova
- York
Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, U.K.
| | - Verena Reiser
- Novozymes
A/S, Krogshøjvej
36, DK-2880 Bagsværd, Denmark
| | - Rakhi Saikia
- Novozymes
A/S, Plot No. 32, 47-50,
Genisys Building, Whitefield, EPIP Zone, Brookefield, Bengaluru, Karnataka 560066, India
| | - Sohel Dalal
- Novozymes
A/S, Plot No. 32, 47-50,
Genisys Building, Whitefield, EPIP Zone, Brookefield, Bengaluru, Karnataka 560066, India
| | | | | | | | | | - Allan Svendsen
- Novozymes
A/S, Krogshøjvej
36, DK-2880 Bagsværd, Denmark
| | - Keith S. Wilson
- York
Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, U.K.
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11
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Function of C-terminal peptides on enzymatic and interfacial adsorption properties of lipase from Gibberella zeae. Biochim Biophys Acta Gen Subj 2018; 1862:2623-2631. [PMID: 30025859 DOI: 10.1016/j.bbagen.2018.07.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 07/12/2018] [Accepted: 07/13/2018] [Indexed: 11/23/2022]
Abstract
BACKGROUND The crystal structure of lipase from Gibberella zeae (GZEL) indicates that its C-terminal extension is composed of a loop and a α-helix. This structure is unique, possibly providing novel evidence on lipase mechanisms. METHODS Two C-terminally truncated mutants (GZEL-Δ(α-helix) and GZEL-Δ(α-helix+loop)) were constructed. The role of these secondary structure segments on enzymatic activities and interfacial binding properties of GZEL was investigated by using conventional pH-stat method and monomolecular film techniques. In addition, inactive variants (Ser144Ala) of wild-type GZEL and two truncated mutants were constructed and produced specifically for interfacial binding experiments. RESULTS Compared to the wild-type GZEL, lipase and phospholipase activities were significantly decreased in the two mutants. Deletion of the α-helix had great influence on the lipase activity of GZEL, resulting in residual 7.3% activity; the additional deletion of the loop led to 8.1% lipase activity. As for the phospholipase function, residual activities of 63.0% and 35.4% were maintained for GZEL-Δ(α-helix) and GZEL-Δ(α-helix+loop), respectively. Findings obtained with monomolecular film experiments further indicated that the reduction in phospholipase activity occurred with the anionic phospholipid as substrate, but was not seen with zwitterionic phospholipid. Results of the maximum insertion pressure, synergy factor and binding kinetic parameters documented that the α-helix structure of GZEL strongly influence the binding and insertion of enzyme to the phospholipid monolayer. Moreover, the interfacial binding function of α-helix was partly conformed by connecting to the C-terminal of Aspergillus oryzae lipase. GENERAL SIGNIFICANCE Our results provide important information on the understanding of the structure-function relationship of GZEL.
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12
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Fungal Screening on Olive Oil for Extracellular Triacylglycerol Lipases: Selection of a Trichoderma harzianum Strain and Genome Wide Search for the Genes. Genes (Basel) 2018; 9:genes9020062. [PMID: 29370083 PMCID: PMC5852558 DOI: 10.3390/genes9020062] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 12/15/2017] [Accepted: 12/20/2017] [Indexed: 11/17/2022] Open
Abstract
A lipolytic screening with fungal strains isolated from lignocellulosic waste collected in banana plantation dumps was carried out. A Trichoderma harzianum strain (B13-1) showed good extracellular lipolytic activity (205 UmL−1). Subsequently, functional screening of the lipolytic activity on Rhodamine B enriched with olive oil as the only carbon source was performed. The successful growth of the strain allows us to suggest that a true lipase is responsible for the lipolytic activity in the B13-1 strain. In order to identify the gene(s) encoding the protein responsible for the lipolytic activity, in silico identification and characterization of triacylglycerol lipases from T. harzianum is reported for the first time. A survey in the genome of this fungus retrieved 50 lipases; however, bioinformatic analyses and putative functional descriptions in different databases allowed us to choose seven lipases as candidates. Suitability of the bioinformatic screening to select the candidates was confirmed by reverse transcription polymerase chain reaction (RT-PCR). The gene codifying 526309 was expressed when the fungus grew in a medium with olive oil as carbon source. This protein shares homology with commercial lipases, making it a candidate for further applications. The success in identifying a lipase gene inducible with olive oil and the suitability of the functional screening and bioinformatic survey carried out herein, support the premise that the strategy can be used in other microorganisms with sequenced genomes to search for true lipases, or other enzymes belonging to large protein families.
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13
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Casas-Godoy L, Gasteazoro F, Duquesne S, Bordes F, Marty A, Sandoval G. Lipases: An Overview. Methods Mol Biol 2018; 1835:3-38. [PMID: 30109644 DOI: 10.1007/978-1-4939-8672-9_1] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Lipases are ubiquitous enzymes, widespread in nature. They were first isolated from bacteria in the early nineteenth century, and the associated research continuously increased due to the characteristics of these enzymes. This chapter reviews the main sources, structural properties, and industrial applications of these highly studied enzymes.
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Affiliation(s)
- Leticia Casas-Godoy
- Cátedras CONACYT-Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco A.C. (CIATEJ), Guadalajara, Jalisco, Mexico.
| | - Francisco Gasteazoro
- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco A.C. (CIATEJ), Guadalajara, Jalisco, Mexico
| | - Sophie Duquesne
- Université de Toulouse, INSA, UPS, INP; LISBP, Toulouse, France.,INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France.,CNRS, UMR5504, Toulouse, France
| | - Florence Bordes
- Université de Toulouse, INSA, UPS, INP; LISBP, Toulouse, France.,INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France.,CNRS, UMR5504, Toulouse, France
| | - Alain Marty
- Université de Toulouse, INSA, UPS, INP; LISBP, Toulouse, France.,INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France.,CNRS, UMR5504, Toulouse, France
| | - Georgina Sandoval
- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco A.C. (CIATEJ), Guadalajara, Jalisco, Mexico
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14
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Recombinant Lipase from Gibberella zeae Exhibits Broad Substrate Specificity: A Comparative Study on Emulsified and Monomolecular Substrate. Int J Mol Sci 2017; 18:ijms18071535. [PMID: 28718792 PMCID: PMC5536023 DOI: 10.3390/ijms18071535] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 07/02/2017] [Accepted: 07/02/2017] [Indexed: 11/17/2022] Open
Abstract
Using the classical emulsified system and the monomolecular film technique, the substrate specificity of recombinant Gibberella zeae lipase (rGZEL) that originates from Gibberella zeae was characterized in detail. Under the emulsified reaction system, both phospholipase and glycolipid hydrolytic activities were observed, except for the predominant lipase activity. The optimum conditions for different activity exhibition were also determined. Compared with its lipase activity, a little higher ratio of glycolipid hydrolytic activity (0.06) than phospholipase activity (0.02) was found. rGZEL preferred medium chain-length triglycerides, while lower activity was found for the longer-chain triglyceride. Using the monomolecular film technique, we found that the preference order of rGZEL to different phospholipids was 1,2-diacyl-sn-glycero-3-phospho-l-serine (PS) > 1,2-dioleoyl-sn-glycero-3-phospho-rac-(1-glycerol) sodium salt (PG) > 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) > l-α-phosphatidylinositol (PI) > cardiolipin (CL) > 3-sn-phosphatidic acid sodium salt (PA) > l-α-phosphatidylethanolamine (PE), while no hydrolytic activity was detected for sphingomyelin (SM). Moreover, rGZEL showed higher galactolipase activity on 1,2-distearoyimonoglactosylglyceride (MGDG). A kinetic study on the stereo- and regioselectivity of rGZEL was also performed by using three pairs of pseudodiglyceride enantiomers (DDGs). rGZEL presented higher preference for distal DDG enantiomers than adjacent ester groups, however, no hydrolytic activity to the sn-2 position of diglyceride analogs was found. Furthermore, rGZEL preferred the R configuration of DDG enantiomers. Molecular docking results were in concordance with in vitro tests.
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15
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A comparative study on kinetics and substrate specificities of Phospholipase A 1 with Thermomyces lanuginosus lipase. J Colloid Interface Sci 2017; 488:149-154. [DOI: 10.1016/j.jcis.2016.10.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/20/2016] [Accepted: 10/20/2016] [Indexed: 11/22/2022]
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16
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An Q, Wang F, Lan D, Khan FI, Durrani R, Yang B, Wang Y. Improving phospholipase activity of PLA
1
by protein engineering and its effects on oil degumming. EUR J LIPID SCI TECH 2017. [DOI: 10.1002/ejlt.201600110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Qun An
- School of Bioscience and BioengineeringSouth China University of TechnologyGuangzhouP. R. China
| | - Fanghua Wang
- School of Food Science and EngineeringState Key Laboratory of Pulp and Paper EngineeringSouth China University of TechnologyGuangzhouP. R. China
| | - Dongming Lan
- School of Food Science and EngineeringState Key Laboratory of Pulp and Paper EngineeringSouth China University of TechnologyGuangzhouP. R. China
| | - Faez Iqbal Khan
- School of Chemistry and Chemical EngineeringHenan University of TechnologyZhengzhouP. R. China
| | - Rabia Durrani
- School of Bioscience and BioengineeringSouth China University of TechnologyGuangzhouP. R. China
| | - Bo Yang
- School of Bioscience and BioengineeringSouth China University of TechnologyGuangzhouP. R. China
| | - Yonghua Wang
- School of Food Science and EngineeringState Key Laboratory of Pulp and Paper EngineeringSouth China University of TechnologyGuangzhouP. R. China
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17
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Jallouli R, Parsiegla G, Carrière F, Gargouri Y, Bezzine S. Efficient heterologous expression of Fusarium solani lipase, FSL2, in Pichia pastoris, functional characterization of the recombinant enzyme and molecular modeling. Int J Biol Macromol 2016; 94:61-71. [PMID: 27620466 DOI: 10.1016/j.ijbiomac.2016.09.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 09/05/2016] [Accepted: 09/08/2016] [Indexed: 11/25/2022]
Abstract
The gene coding for a lipase of Fusarium solani, designated as FSL2, shows an open reading frame of 906bp encoding a 301-amino acid polypeptide with a molecular mass of 30kDa. Based on sequence similarity with other fungal lipases, FSL2 contains a catalytic triad, consisting of Ser144, Asp198, and His256. FSL2 cDNA was subcloned into the pGAPZαA vector containing the Saccharomyces cerevisiae α-factor signal sequence and this construct was used to transform Pichia pastoris and achieve a high-level extracellular production of a FSL2 lipase. Maximum lipase activity was observed after 48h. The optimum activity of the purified recombinant enzyme was measured at pH 8.0-9.0 and 37°C. FSL2 is remarkably stable at alkaline pH values up to 12 and at temperatures below 40°C. It has high catalytic efficiency towards triglycerides with short to long chain fatty acids but with a marked preference for medium and long chain fatty acids. FSL2 activity is decreased at sodium taurodeoxycholate concentrations above the Critical Micelle Concentration (CMC) of this anionic detergent. However, lipase activity is enhanced by Ca2+ and inhibited by EDTA or Cu2+ and partially by Mg2+ or K+. In silico docking of medium chain triglycerides, monogalctolipids (MGDG), digalactolipids (DGDG) and long chain phospholipids in the active site of FSL2 reveals structural solutions.
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Affiliation(s)
- Raida Jallouli
- University of Sfax, Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS route de Soukra, BPW 3038 Sfax, Tunisie
| | - Goetz Parsiegla
- CNRS, Aix Marseille Université, Enzymologie Interfaciale et Physiologie de la Lipolyse UMR7282, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France
| | - Frédéric Carrière
- CNRS, Aix Marseille Université, Enzymologie Interfaciale et Physiologie de la Lipolyse UMR7282, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France
| | - Youssef Gargouri
- University of Sfax, Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS route de Soukra, BPW 3038 Sfax, Tunisie
| | - Sofiane Bezzine
- University of Sfax, Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS route de Soukra, BPW 3038 Sfax, Tunisie.
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18
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The galactolipase activity of Fusarium solani (phospho)lipase. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:282-9. [DOI: 10.1016/j.bbalip.2014.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 12/06/2014] [Accepted: 12/11/2014] [Indexed: 11/16/2022]
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19
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Kamoun J, Schué M, Messaoud W, Baignol J, Point V, Mateos-Diaz E, Mansuelle P, Gargouri Y, Parsiegla G, Cavalier JF, Carrière F, Aloulou A. Biochemical characterization of Yarrowia lipolytica LIP8, a secreted lipase with a cleavable C-terminal region. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:129-40. [DOI: 10.1016/j.bbalip.2014.10.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 10/23/2014] [Accepted: 10/27/2014] [Indexed: 10/24/2022]
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20
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New tools for exploring "old friends-microbial lipases". Appl Biochem Biotechnol 2012; 168:1163-96. [PMID: 22956276 DOI: 10.1007/s12010-012-9849-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Accepted: 08/20/2012] [Indexed: 10/27/2022]
Abstract
Fat-splitting enzymes (lipases), due to their natural, industrial, and medical relevance, attract enough attention as fats do in our lives. Starting from the paper that we write, cheese and oil that we consume, detergent that we use to remove oil stains, biodiesel that we use as transportation fuel, to the enantiopure drugs that we use in therapeutics, all these applications are facilitated directly or indirectly by lipases. Due to their uniqueness, versatility, and dexterity, decades of research work have been carried out on microbial lipases. The hunt for novel lipases and strategies to improve them continues unabated as evidenced by new families of microbial lipases that are still being discovered mostly by metagenomic approaches. A separate database for true lipases termed LIPABASE has been created recently which provides taxonomic, structural, biochemical information about true lipases from various species. The present review attempts to summarize new approaches that are employed in various aspects of microbial lipase research, viz., screening, isolation, production, purification, improvement by protein engineering, and surface display. Finally, novel applications facilitated by microbial lipases are also presented.
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Xu T, Liu L, Hou S, Xu J, Yang B, Wang Y, Liu J. Crystal structure of a mono- and diacylglycerol lipase from Malassezia globosa reveals a novel lid conformation and insights into the substrate specificity. J Struct Biol 2012; 178:363-9. [PMID: 22484238 DOI: 10.1016/j.jsb.2012.03.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Revised: 03/01/2012] [Accepted: 03/03/2012] [Indexed: 10/28/2022]
Abstract
Most lipases contain a lid domain to shield the hydrophobic binding site from the water environment. The lid, mostly in helical form, can undergo a conformational change to expose the active cleft during the interfacial activation. Here we report the crystal structures of Malassezia globosa LIP1 (SMG1) at 1.45 and 2.60 Å resolution in two crystal forms. The structures present SMG1 in its closed form, with a novel lid in loop conformation. SMG1 is one of the few members in the fungal lipase family that has been found to be strictly specific for mono- and diacylglycerol. To date, the mechanism for this substrate specificity remains largely unknown. To investigate the substrate binding properties, we built a model of SMG1 in open conformation. Based on this model, we found that the two bulky hydrophobic residues adjacent to the catalytic site and the N-terminal hinge region of the lid both may act as steric hindrances for triacylglycerols binding. These unique structural features of SMG1 will provide a better understanding on the substrate specificity of mono- and diacylglycerol lipases and a platform for further functional study of this enzyme.
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Affiliation(s)
- Tingting Xu
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, People's Republic of China
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22
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Zheng B, Yang W, Wang Y, Lou Z, Feng Y. Influence of the N-terminal peptide on the cocrystallization of a thermophilic endo-β-1,4-glucanase with polysaccharide substrates. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:1218-20. [PMID: 22102031 DOI: 10.1107/s1744309111033550] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 08/17/2011] [Indexed: 11/10/2022]
Abstract
It is well known that protein cocrystallization is affected by several parameters such as the ratio of the protein to the ligand, the reservoir solution, the pH and the temperature. Previously, spatial blocking by the N-terminus was observed in the active site in the crystal structure of the native protein of a thermostable endoglucanase from the thermophilic bacterium Fervidobacterium nodosum Rt17-B1 (FnCel5A). It was speculated that the N-terminal α-helix might form interactions with the substrate-binding residues and it was believed that this spatial block is special to some extent. In order to confirm the effect on cocrystallization, two N-terminally truncated variants of FnCel5A were constructed, purified and cocrystallized at 291 K. A crystal of FnCel5AND_12-343 in complex with cellobiose was obtained using PEG 8000 as a precipitant. A 2.2 Å resolution data set was collected. This crystal form (space group P4(1)2(1)2, unit-cell parameters a = b = 47.3, c = 271.4 Å) differed from that of the native protein. One molecule is assumed to be present per asymmetric unit, which gives a Matthews coefficient of 2.05 Å(3) Da(-1).
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Affiliation(s)
- Baisong Zheng
- Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, Jilin University, Changchun 130023, People's Republic of China
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