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Patarroyo-Vargas AM, Cordeiro G, Silva CRDA, Silva CRDA, Mendonça EG, Visôtto LE, Zanuncio JC, Campos WG, Oliveira MGA. Inhibition kinetics of digestive proteases for Anticarsia gemmatalis. AN ACAD BRAS CIENC 2020; 92 Suppl 1:e20180477. [PMID: 32491140 DOI: 10.1590/0001-3765202020180477] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 03/26/2019] [Indexed: 11/22/2022] Open
Abstract
Anticarsia gemmatalis Hübner, 1818 (Lepidoptera) is a major pest of soybean in the Brazil. It is known that the reduction of proteolytic activity by the ingestion of protease inhibitors reduces digestion and larval development of the insects. Control via inhibition of the digestive enzymes necessitates deeper knowledge of the enzyme kinetics and the characterization of the inhibition kinetics of these proteases, for better understanding of the active centers and action mechanisms of this enzyme. Trypsin-like proteases found in the gut of Anticarsia gemmatalis were purified in a p-aminobenzamidine agarose column. Kinetic characterization showed KM 0.503 mM for the L-BApNA substrate; Vmax= 46.650 nM s-1; Vmax/[E]= 9.256 nM s-1 mg L-1 and Vmax/[E]/KM= 18.402 nM s-1 mg L-1 mM. The Ki values for the inhibitors benzamidine, berenil, SKTI and SBBI were 11.2 µM, 32.4 µM, 0.25 nM and 1.4 nM, respectively, and all revealed linear competitive inhibition. The SKTI showed the greatest inhibition, which makes it a promising subject for future research to manufacture peptide mimetic inhibitors.
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Affiliation(s)
- Adriana M Patarroyo-Vargas
- Departamento de Bioquímica e Biologia Molecular, Instituto de Biotecnologia Aplicada a Agropecuária/BIOAGRO, Viçosa, MG, Brazil
| | - Gláucia Cordeiro
- Departamento de Bioquímica e Biologia Molecular, Instituto de Biotecnologia Aplicada a Agropecuária/BIOAGRO, Viçosa, MG, Brazil
| | - Carolina R DA Silva
- Departamento de Bioquímica e Biologia Molecular, Instituto de Biotecnologia Aplicada a Agropecuária/BIOAGRO, Viçosa, MG, Brazil
| | - Camila R DA Silva
- Instituto de Ciências Agrárias, Universidade Federal de Viçosa, Rio Paranaíba, MG, Brazil
| | - Eduardo G Mendonça
- Departamento de Bioquímica e Biologia Molecular, Instituto de Biotecnologia Aplicada a Agropecuária/BIOAGRO, Viçosa, MG, Brazil
| | - Liliane E Visôtto
- Instituto de Ciências Biológicas, Universidade Federal de Viçosa, Rio Paranaíba, MG, Brazil
| | - José C Zanuncio
- Departamento de Entomologia, Instituto de Biotecnologia Aplicada a Agropecuária/ BIOAGRO, Viçosa, MG, Brazil
| | - Welligton G Campos
- Departamento de Engenharia de Biossistemas, Universidade Federal de São João Del-Rei, São João Del-Rei, MG, Brazil
| | - Maria Goreti A Oliveira
- Departamento de Bioquímica e Biologia Molecular, Instituto de Biotecnologia Aplicada a Agropecuária/BIOAGRO, Viçosa, MG, Brazil
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Holtof M, Lenaerts C, Cullen D, Vanden Broeck J. Extracellular nutrient digestion and absorption in the insect gut. Cell Tissue Res 2019; 377:397-414. [DOI: 10.1007/s00441-019-03031-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 04/04/2019] [Indexed: 02/07/2023]
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3
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Zhou T, Wang X, Yan J, Li Y. Gene analysis and structure prediction for the cold-adaption mechanism of trypsin from the krill Euphausia superba (Dana, 1852). JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2018; 98:3049-3056. [PMID: 29194642 DOI: 10.1002/jsfa.8804] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 11/13/2017] [Accepted: 11/26/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND The ability of Antarctic krill, Euphausia superba (Dana, 1852), to thrive in a cold environment comes from its capacity to synthesize cold-adapted enzymes. Its trypsin, as a main substance in the metabolic reactions, plays a key role in the adaption to low temperatures. However, the progress of research on its cold-adaption mechanism is being influenced due to the limited information on its gene and spatial structure. RESULTS We studied the gene of E. superba trypsin with transcriptome sequencing first, and then discussed its cold-adaption mechanism with the full gene and predicted structure basing on bioinformatics. The results showed the proportion of certain residues played important roles in the cold-adaptation behavior for trypsin. Furthermore, a higher proportion of random coils and reduced steric hindrance might also be key factors promoting its cold adaption. CONCLUSION This research aimed to reveal the cold-adaption mechanism of E. superba trypsin and provide support for basic research on molecular modification by site-directed mutagenesis of complementary DNA used to produce new and improved recombinant variants with cold adaption. Furthermore, it may broaden its commercial application on minimizing undesirable changes elevated at higher temperature in food processing and in treatment of trauma and inflammation in medicine. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Tingting Zhou
- College of Food Science and Technology, Shanghai Ocean University, 999# Hu Cheng Huan Road, Shanghai, P. R. China
| | - Xichang Wang
- College of Food Science and Technology, Shanghai Ocean University, 999# Hu Cheng Huan Road, Shanghai, P. R. China
- Shanghai Engineering Research Center of Aquatic-Product Processing & Preservation, Shanghai, China
- Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture, Shanghai, China
| | - Juan Yan
- College of Food Science and Technology, Shanghai Ocean University, 999# Hu Cheng Huan Road, Shanghai, P. R. China
- Shanghai Engineering Research Center of Aquatic-Product Processing & Preservation, Shanghai, China
- Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture, Shanghai, China
| | - Yan Li
- College of Food Science and Technology, Shanghai Ocean University, 999# Hu Cheng Huan Road, Shanghai, P. R. China
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4
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Carrazoni T, Nguyen C, Maciel LF, Delgado-Cañedo A, Stewart BA, Lange AB, Dal Belo CA, Carlini CR, Orchard I. Jack bean urease modulates neurotransmitter release at insect neuromuscular junctions. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2018; 146:63-70. [PMID: 29626993 DOI: 10.1016/j.pestbp.2018.02.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 02/09/2018] [Accepted: 02/21/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Plants have developed a vast range of mechanisms to compete with phytophagous insects, including entomotoxic proteins such as ureases. The legume Canavalia ensiformis produces several urease isoforms, of which the more abundant is called Jack Bean Urease (JBU). Previews work has demonstrated the potential insecticidal effects of JBU, by mechanisms so far not entirely elucidated. In this work, we investigated the mechanisms involved in the JBU-induced activity upon neurotransmitter release on insect neuromuscular junctions. METHODS Electrophysiological recordings of nerve and muscle action potentials, and calcium imaging bioassays were employed. RESULTS AND CONCLUSION JBU (0.28 mg/animal/day) in Locusta migratoria 2nd instar through feeding and injection did not induce lethality, although it did result in a reduction of 20% in the weight gain at the end of 168 h (n = 9, p ≤ 0.05). JBU (0.014 and 0.14 mg) injected direct into the locust hind leg induced a dose and time-dependent decrease in the amplitude of muscle action potentials, with a maximum decrease of 70% in the amplitude at the highest dose (n = 5, p ≤ 0.05). At the same doses JBU did not alter the amplitude of action potentials evoked from motor neurons. Using Drosophila 3rd instar larvae neuromuscular preparations, JBU (10-7 M) increased the occurrence of miniature Excitatory Junctional Potentials (mEJPs) in the presence of 1 mM CaCl2 (n = 5, p ≤ 0.05). In low calcium (0.4 mM) assays, JBU (10-7 M) was not able to modulate the occurrence of the events. In Ca2+-free conditions, with EGTA or CoCl2, JBU induced a significant decrease in the occurrence of mEPJs (n = 5, p ≤ 0.05). Injected into the 3rd abdominal ganglion of Nauphoeta cinerea cockroaches, JBU (1 μM) induced a significant increase in Ca2+ influx (n = 7, p ≤ 0.01), similar to that seen for high KCl (35 mM) condition. Taken together the results confirm a direct action of JBU upon insect neuromuscular junctions and possibly central synapses, probably by disrupting the calcium machinery in the pre-synaptic region of the neurons.
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Affiliation(s)
- Thiago Carrazoni
- Universidade Federal do Rio Grande do Sul, Graduate Program in Cell and Molecular Biology, Center of Biotechnology, Porto Alegre, RS, Brazil; University of Toronto Mississauga, Department of Biology, Mississauga, ON, Canada; Pontifícia Universidade Católica do Rio Grande de Sul, Brain Institute, Porto Alegre, RS, Brazil.
| | - Christine Nguyen
- University of Toronto Mississauga, Department of Biology, Mississauga, ON, Canada
| | - Lucas F Maciel
- Universidade Federal do Pampa, Campus São Gabriel, São Gabriel, RS, Brazil
| | | | - Bryan A Stewart
- University of Toronto Mississauga, Department of Biology, Mississauga, ON, Canada
| | - Angela B Lange
- University of Toronto Mississauga, Department of Biology, Mississauga, ON, Canada
| | | | - Celia R Carlini
- Universidade Federal do Rio Grande do Sul, Graduate Program in Cell and Molecular Biology, Center of Biotechnology, Porto Alegre, RS, Brazil; Pontifícia Universidade Católica do Rio Grande de Sul, Brain Institute, Porto Alegre, RS, Brazil.
| | - Ian Orchard
- University of Toronto Mississauga, Department of Biology, Mississauga, ON, Canada.
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Nongonierma AB, Lamoureux C, FitzGerald RJ. Generation of dipeptidyl peptidase IV (DPP-IV) inhibitory peptides during the enzymatic hydrolysis of tropical banded cricket (Gryllodes sigillatus) proteins. Food Funct 2018; 9:407-416. [DOI: 10.1039/c7fo01568b] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cricket (Gryllodes sigillatus) protein hydrolysates inhibit dipeptidyl peptidase IV (DPP-IV) in vitro.
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Affiliation(s)
- Alice B. Nongonierma
- Department of Biological Sciences
- University of Limerick
- Limerick
- Ireland
- Food for Health Ireland (FHI)
| | - Candice Lamoureux
- Department of Biological Sciences
- University of Limerick
- Limerick
- Ireland
| | - Richard J. FitzGerald
- Department of Biological Sciences
- University of Limerick
- Limerick
- Ireland
- Food for Health Ireland (FHI)
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Transcriptional Analysis of The Adaptive Digestive System of The Migratory Locust in Response to Plant Defensive Protease Inhibitors. Sci Rep 2016; 6:32460. [PMID: 27581362 PMCID: PMC5007527 DOI: 10.1038/srep32460] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 08/05/2016] [Indexed: 11/28/2022] Open
Abstract
Herbivorous insects evolved adaptive mechanisms to compensate for the presence of plant defensive protease inhibitors (PI) in their food. The underlying regulatory mechanisms of these compensatory responses remain largely elusive. In the current study, we investigated the initiation of this adaptive response in the migratory locust, Locusta migratoria, via microarray analysis of gut tissues. Four hours after dietary uptake of PIs, 114 and 150 transcripts were respectively found up- or downregulated. The results suggest a quick trade-off between compensating for potential loss of digestive activity on the one hand, and stress tolerance, defense, and structural integrity of the gut on the other hand. We additionally addressed the role of a group of related upregulated hexamerin-like proteins in the PI-induced response. Simultaneous knockdown of corresponding transcripts by means of RNA interference resulted in a reduced capacity of the locust nymphs to cope with the effects of PI. Moreover, since insect hexamerins have been shown to bind Juvenile Hormone (JH), we also investigated the effect of JH on the proteolytic digestion in L. migratoria. Our results indicate that JH has a stimulatory effect on the expression of three homologous chymotrypsin genes, while knocking down the JH receptor (methoprene tolerant) led to opposite effects.
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7
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Medel V, Palma R, Mercado D, Rebolledo R, Quiroz A, Mutis A. The Effect of Protease Inhibitors on Digestive Proteolytic Activity in the Raspberry Weevil, Aegorhinus superciliosus (Guérin) (Coleoptera: Curculionidae). NEOTROPICAL ENTOMOLOGY 2015; 44:77-83. [PMID: 26013015 DOI: 10.1007/s13744-014-0250-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 10/13/2014] [Indexed: 06/04/2023]
Abstract
The raspberry weevil, Aegorhinus superciliosus (Guérin) (Coleoptera: Curculionidae), is an economically important pest of blueberry in southern Chile. The digestive protease activity of adult insects was investigated using general and specific substrates and inhibitors. Enzymatic assays demonstrated the presence of trypsin- and chymotrypsin-like serine proteinases. Furthermore, in vitro assays using phenylmethylsulfonyl fluoride (PMSF) and soybean trypsin inhibitor (SBTI) at 0.01 and 0.1 mM showed percentages of enzymatic inhibition between 0 and 16% for PMSF and 67 to 76% for SBTI, whereas in vivo assays indicated that SBTI caused between 50 and 90% mortality in males and between 80 and 100% in females. Our data indicate the presence of serine proteases and suggest that digestive proteases could be a target for the design and development of strategies to control the raspberry weevil.
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Affiliation(s)
- V Medel
- Lab de Química Ecológica, Depto de Ciencias Químicas y Recursos Naturales, Univ de La Frontera, Temuco, Araucanía, Chile
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Lima TDA, Pontual EV, Dornelles LP, Amorim PK, Sá RA, Coelho LCBB, Napoleão TH, Paiva PMG. Digestive enzymes from workers and soldiers of termite Nasutitermes corniger. Comp Biochem Physiol B Biochem Mol Biol 2014; 176:1-8. [DOI: 10.1016/j.cbpb.2014.07.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Revised: 06/28/2014] [Accepted: 07/02/2014] [Indexed: 10/25/2022]
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9
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Spit J, Zels S, Dillen S, Holtof M, Wynant N, Vanden Broeck J. Effects of different dietary conditions on the expression of trypsin- and chymotrypsin-like protease genes in the digestive system of the migratory locust, Locusta migratoria. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 48:100-109. [PMID: 24650544 DOI: 10.1016/j.ibmb.2014.03.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Revised: 03/06/2014] [Accepted: 03/06/2014] [Indexed: 06/03/2023]
Abstract
While technological advancements have recently led to a steep increase in genomic and transcriptomic data, and large numbers of protease sequences are being discovered in diverse insect species, little information is available about the expression of digestive enzymes in Orthoptera. Here we describe the identification of Locusta migratoria serine protease transcripts (cDNAs) involved in digestion, which might serve as possible targets for pest control management. A total of 5 putative trypsin and 15 putative chymotrypsin gene sequences were characterized. Phylogenetic analysis revealed that these are distributed among 3 evolutionary conserved clusters. In addition, we have determined the relative gene expression levels of representative members in the gut under different feeding conditions. This study demonstrated that the transcript levels for all measured serine proteases were strongly reduced after starvation. On the other hand, larvae of L. migratoria displayed compensatory effects to the presence of Soybean Bowman Birk (SBBI) and Soybean Trypsin (SBTI) inhibitors in their diet by differential upregulation of multiple proteases. A rapid initial upregulation was observed for all tested serine protease transcripts, while only for members belonging to class I, the transcript levels remained elevated after prolonged exposure. In full agreement with these results, we also observed an increase in proteolytic activity in midgut secretions of locusts that were accustomed to the presence of protease inhibitors in their diet, while no change in sensitivity to these inhibitors was observed. Taken together, this paper is the first comprehensive study on dietary dependent transcript levels of proteolytic enzymes in Orthoptera. Our data suggest that compensatory response mechanisms to protease inhibitor ingestion may have appeared early in insect evolution.
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Affiliation(s)
- Jornt Spit
- Department of Animal Physiology and Neurobiology, Zoological Institute K.U.Leuven, Naamsestraat 59, B-3000 Leuven, Belgium.
| | - Sven Zels
- Department of Animal Physiology and Neurobiology, Zoological Institute K.U.Leuven, Naamsestraat 59, B-3000 Leuven, Belgium
| | - Senne Dillen
- Department of Animal Physiology and Neurobiology, Zoological Institute K.U.Leuven, Naamsestraat 59, B-3000 Leuven, Belgium
| | - Michiel Holtof
- Department of Animal Physiology and Neurobiology, Zoological Institute K.U.Leuven, Naamsestraat 59, B-3000 Leuven, Belgium
| | - Niels Wynant
- Department of Animal Physiology and Neurobiology, Zoological Institute K.U.Leuven, Naamsestraat 59, B-3000 Leuven, Belgium
| | - Jozef Vanden Broeck
- Department of Animal Physiology and Neurobiology, Zoological Institute K.U.Leuven, Naamsestraat 59, B-3000 Leuven, Belgium
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Brabcová J, Kindl J, Valterová I, Pichová I, Zarevúcka M, Brabcová J, Jágr M, Mikšík I. Serine protease from midgut of Bombus terrestris males. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2013; 82:117-128. [PMID: 23303700 DOI: 10.1002/arch.21075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A serine protease was isolated from midguts of the bumblebee male Bombus terrestris by a combination of precipitation procedures with column chromatography. The purified enzyme exhibited two bands with molecular masses of 25 and 26 kDa as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. These bands showed a proteolytic activity in zymography assay. Midgut enzymes showed optimum proteolytic activity at pH 9 and 35°C using N-succinyl-L-alanyl-L-alanyl-L-prolyl-L-phenyl-alanine 4-nitroanilide as a substrate. The Michaelis constant (Km) and maximum reaction rate (Vmax) were 0.55±0.042 mM and 0.714±0.056 μmol p-nitroalanine produced min(-1) mg protein(-1) , respectively. Inhibition was affected by trypsin inhibitor, but not by phenylmethylsulfonyl fluoride and N-tosyl-L-phenylalanine chloromethyl ketone, which indicated the trypsin-like but not chymotrypsin-like specificity. The identity of the serine protease was confirmed by nanoliquid-tandem mass spectrometry. Eleven unique peptides of the B. terrestris serine protease were found. It shows high homology to a previously reported B. ignitus serine protease covering more than 65% of the protein amino acid sequence.
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Affiliation(s)
- Jana Brabcová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
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Jitonnom J, Lomthaisong K, Lee VS. Computational Design of Peptide Inhibitor Based on Modifications of Proregion from Plutella xylostella Midgut Trypsin. Chem Biol Drug Des 2012; 79:583-93. [DOI: 10.1111/j.1747-0285.2011.01312.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Soares TS, Watanabe RM, Lemos FJ, Tanaka AS. Molecular characterization of genes encoding trypsin-like enzymes from Aedes aegypti larvae and identification of digestive enzymes. Gene 2011; 489:70-5. [DOI: 10.1016/j.gene.2011.08.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2011] [Revised: 07/25/2011] [Accepted: 08/26/2011] [Indexed: 10/17/2022]
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13
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Chi YH, Jing X, Lei J, Ahn JE, Koo YD, Yun DJ, Lee SY, Behmer ST, Koiwa H, Zhu-Salzman K. Stability of AtVSP in the insect digestive canal determines its defensive capability. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:391-9. [PMID: 21192943 DOI: 10.1016/j.jinsphys.2010.12.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 12/19/2010] [Accepted: 12/20/2010] [Indexed: 05/03/2023]
Abstract
We have previously demonstrated that Arabidopsis vegetative storage protein (AtVSP) is an acid phosphatase that has anti-insect activity in in vitro feeding assays [Liu et al., 2005. Plant Physiology 139, 1545-1556]. To investigate the functionality of AtVSP in planta as an anti-insect defense protein, we produced AtVSP-overexpressing as well as AtVSP-silenced transgenic Arabidopsis lines, and evaluated impact on the polyphagous American grasshopper Schistocerca americana. Grasshoppers showed no significant difference in weight gain and growth rate when feeding on wild type, overexpressing, or silenced lines, respectively. In addition, AtVSP protein was undetectable in either the midgut or frass of grasshoppers reared on transgenic plants suggesting that AtVSP was unable to withstand proteolytic degradation. To determine the stability of the AtVSP protein in grasshopper digestive canal, midgut extracts from various nymphal stages were incubated with bacterially expressed AtVSP for different periods of time. AtVSP was hydrolyzed rapidly by grasshopper midgut extract, in stark contrast with its fate when incubated with cowpea bruchid midgut extract. Multiple proteases have been detected in the midgut of grasshoppers, which may play important roles in determining the insect response to AtVSP. Results indicate that stability of an anti-insect protein in insect guts is a crucial property integral to the defense protein.
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Affiliation(s)
- Yong Hun Chi
- Department of Entomology, Texas A&M University, College Station, TX 77843, USA
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14
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Loncar N, Vujcić Z, Bozić N, Ivanović J, Nenadović V. Purification and properties of trypsin-like enzyme from the midgut of Morimus funereus (coleoptera, cerambycidae) Larvae. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2010; 74:232-246. [PMID: 20549815 DOI: 10.1002/arch.20371] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Trypsin-like enzyme (TLE) from the anterior midgut of Morimus funereus larvae was purified by anion exchange chromatography and gel filtration chromatography and characterized. Specific TLE activity was increased 322-fold by purification of the crude midgut extract. The purified enzyme had a pH optimum of 9.0 (optimum pH range 8.5-9.5) and temperature optimum of 45 degrees C with the K(M) ratio of 0.065 mM for benzoyl-arginine-p-nitroanilide (BApNA). Among a number of inhibitors tested, the most efficient was benzamidine (K(I) value of 0.012 mM, Ic(50) value of 0.204 mM) while inhibition of TLE activity by SBTI, TLCK, and PMSF was partial. Almost all divalent cations tested enhanced the enzyme activity, amongst them Co2+ and Mn2+ stimulated TLE activity for 2.5 times. The purified TLE (after gel-filtration on Superose 12 column) had a molecular mass of 37.5 kDa with an isoelectric point over 9.3. Sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed one band of 38 kDa, suggesting that the enzyme is a monomer.
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Affiliation(s)
- Nikola Loncar
- Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Belgrade, Serbia
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15
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Abstract
The MEROPS website (http://merops.sanger.ac.uk) includes information on peptidase inhibitors as well as on peptidases and their substrates. Displays have been put in place to link peptidases and inhibitors together. The classification of protein peptidase inhibitors is continually being revised, and currently inhibitors are grouped into 67 families based on comparisons of protein sequences. These families can be further grouped into 38 clans based on comparisons of tertiary structure. Small molecule inhibitors are important reagents for peptidase characterization and, with the increasing importance of peptidases as drug targets, they are also important to the pharmaceutical industry. Small molecule inhibitors are now included in MEROPS and over 160 summaries have been written.
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Affiliation(s)
- Neil D Rawlings
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridgeshire CB10 1SA, UK.
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Clissold FJ, Tedder BJ, Conigrave AD, Simpson SJ. The gastrointestinal tract as a nutrient-balancing organ. Proc Biol Sci 2010; 277:1751-9. [PMID: 20129973 DOI: 10.1098/rspb.2009.2045] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Failure to provision tissues with an appropriate balance of nutrients engenders fitness costs. Maintaining nutrient balance can be achieved by adjusting the selection and consumption of foods, but this may not be possible when the nutritional environment is limiting. Under such circumstances, rebalancing of an imbalanced nutrient intake requires post-ingestive mechanisms. The first stage at which such post-ingestive rebalancing might occur is within the gastrointestinal tract (GIT), by differential release of digestive enzymes-releasing less of those enzymes for nutrients present in excess while maintaining or boosting levels of enzymes for nutrients in deficit. Here, we use an insect herbivore, the locust, to show for the first time that such compensatory responses occur within the GIT. Furthermore, we show that differential release of proteases and carbohydrases in response to nutritional state translate into differential extraction of macronutrients from host plants. The prevailing view is that physiological and structural plasticity in the GIT serves to maximize the rate of nutrient gain in relation to costs of maintaining the GIT; our findings show that GIT plasticity is integral to the maintenance of nutrient balance.
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Silva L, Reis A, Pereira E, Oliveira M, Guedes R. Partial purification and characterization of trypsin-like proteinases from insecticide-resistant and -susceptible strains of the maize weevil, Sitophilus zeamais. Comp Biochem Physiol B Biochem Mol Biol 2010; 155:12-9. [DOI: 10.1016/j.cbpb.2009.09.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 09/01/2009] [Accepted: 09/02/2009] [Indexed: 11/28/2022]
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18
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Invertebrate trypsins: a review. J Comp Physiol B 2008; 178:655-72. [DOI: 10.1007/s00360-008-0263-y] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 03/18/2008] [Accepted: 03/25/2008] [Indexed: 11/26/2022]
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Detection of genes encoding antimicrobial peptides in Mexican strains of Trichoplusia ni (Hübner) exposed to Bacillus thuringiensis. J Invertebr Pathol 2008; 98:218-27. [PMID: 18359041 DOI: 10.1016/j.jip.2008.02.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 02/01/2008] [Accepted: 02/13/2008] [Indexed: 11/23/2022]
Abstract
The systemic immune response of Trichoplusia ni after Bacillus thuringiensis (Bt) exposure was evaluated by comparing the expression of genes encoding antimicrobial peptides (AMPs) in Bt-susceptible and -resistant T. ni strains that were either exposed or not to XenTari (Bt-XT). AMP genes were detected by RT-PCR using primers for attacin, gloverin, lebocin, lysozyme, and peptidoglycan recognition peptide (PGRP). In general, AMP genes were detected more frequently in Mexican field strains previously exposed to Bt (SALX and GTOX) than in a Mexican laboratory strain (NL), but expression was similar to the AMP expression in USA laboratory strains (US and USX). Among the AMPs, transcripts for lebocin were the least detected (11.7%) and those for lysozyme were the most detected (84.8%) in all samples. Lebocin was detected only in 2nd instar and pupa. All untreated controls expressed attacin. Attacin and gloverin were not detected in any midgut sample, and their highest detection was in pupa. Lysozyme was rarely detected in 2nd instar larvae from any strain or treatment but was detected in almost all midgut and hemolymph samples. Overall, AMPs were found more in T. ni strains previously exposed to Bt-XT, especially lebocin and globerin (1.8-fold increase) and PGRP (3.8-fold increase). The data suggest that the expression of AMPs in T. ni correlates to previous Bt exposure.
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20
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Díaz-Mendoza M, Ortego F, García de Lacoba M, Magaña C, de la Poza M, Farinós GP, Castañera P, Hernández-Crespo P. Diversity of trypsins in the Mediterranean corn borer Sesamia nonagrioides (Lepidoptera: Noctuidae), revealed by nucleic acid sequences and enzyme purification. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2005; 35:1005-20. [PMID: 15979001 DOI: 10.1016/j.ibmb.2005.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Revised: 04/11/2005] [Accepted: 04/12/2005] [Indexed: 05/03/2023]
Abstract
The existence of a diverse trypsin gene family with a main role in the proteolytic digestion process has been proved in vertebrate and invertebrate organisms. In lepidopteran insects, a diversity of trypsin-like genes expressed in midgut has also been identified. Genomic DNA and cDNA trypsin-like sequences expressed in the Mediterranean corn Borer (MCB), Sesamia nonagrioides, midgut are reported in this paper. A phylogenetic analysis revealed that at least three types of trypsin-like enzymes putatively involved in digestion are conserved in MCB and other lepidopteran species. As expected, a diversity of sequences has been found, including four type-I (two subtypes), four type-II (two subtypes) and one type-III. In parallel, four different trypsins have been purified from midgut lumen of late instar MCB larvae. N-terminal sequencing and mass spectrometric analyses of purified trypsins have been performed in order to identify cDNAs coding for major trypsins among the diversity of trypsin-like sequences obtained. Thus, it is revealed that the four purified trypsins in MCB belong to the three well-defined phylogenetic groups of trypsin-like sequences detected in Lepidoptera. Major active trypsins present in late instar MCB lumen guts are trypsin-I (type-I), trypsin-IIA and trypsin-IIB (type-II), and trypsin-III (type-III). Trypsin-I, trypsin-IIA and trypsin-III showed preference for Arg over Lys, but responded differently to proteinaceous or synthetic inhibitors. As full-length cDNA clones coding for the purified trypsins were available, three-dimensional protein models were built in order to study the implication of specific residues on their response to inhibitors. Thus, it is predicted that Arg73, conserved in type-I lepidopteran trypsins, may favour reversible inhibition by the E-64. Indeed, the substitution of Val213Cys, unique for type-II lepidopteran trypsins, may be responsible for their specific inhibition by HgCl2. The implication of these results on the optimisation of the use of protease inhibitors for pest control, and on the identification of endoprotease-mediated resistance to Bacillus thuringiensis Cry-toxins is discussed.
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Affiliation(s)
- M Díaz-Mendoza
- Dpto. Biología de Plantas, Laboratorio de Interacciones Planta-Insecto, Centro de Investigaciones Biológicas-C.S.I.C., Ramiro de Maeztu 9, 28040 Madrid, Spain
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Kvamme BO, Kongshaug H, Nilsen F. Organisation of trypsin genes in the salmon louse (Lepeophtheirus salmonis, Crustacea, copepoda) genome. Gene 2005; 352:63-74. [PMID: 15878809 DOI: 10.1016/j.gene.2005.03.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2004] [Revised: 02/24/2005] [Accepted: 03/14/2005] [Indexed: 11/26/2022]
Abstract
Trypsins constitute a subclass of the S1A family of serine peptidases found in all groups of animal and some bacteria. At present, no information about the genomic organisation of trypsins is available for copepods. The only data of copepod trypsins indicate several different trypsins in the marine parasitic copepod Lepeophtheirus salmonis. In the present study, 31.7 kbp of genomic DNA surrounding the previously described LsTryp1-5 sequences was sequenced. The sequenced regions contain nine full-length and three partial trypsin genes. A conservative estimate based on PCR analysis and genomic sequence indicated at least 22 different trypsin genes in L. salmonis, of which 18 are most similar to the previously described LsTryp1 and -2 cDNA sequences. Four of these genes are putative pseudogenes. In addition, a putative mariner like transposase gene was identified. The genomic sequences suggest that the L. salmonis trypsin genes reside within one or more gene clusters. Three different LsTryp intron exon structures were identified, and all three are different from the intron exon organisation previously reported for other S1A peptidases. This implies several intron loss and gain events in the evolution of the L. salmonis trypsin genes.
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Affiliation(s)
- Bjørn Olav Kvamme
- Institute of Marine Research, P.O. Box 1870 Nordnes, 5817 Bergen, Norway.
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22
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Oliveira MGA, De Simone SG, Xavier LP, Guedes RNC. Partial purification and characterization of digestive trypsin-like proteases from the velvet bean caterpillar, Anticarsia gemmatalis. Comp Biochem Physiol B Biochem Mol Biol 2005; 140:369-80. [PMID: 15694584 DOI: 10.1016/j.cbpc.2004.10.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2004] [Revised: 10/29/2004] [Accepted: 10/31/2004] [Indexed: 10/26/2022]
Abstract
Trypsin-like proteases from the midgut of Anticarsia gemmatalis Hubner (Lepidoptera: Noctuidae) were purified on an aprotinin-agarose column equilibrated with 0.01 M Tris-HCl containing 5 mM CaCl2 (pH 7.5). The yield was 66.7% with a purification factor of 107 and a final specific activity of 6.88 mM/min/mg protein with the substrate N-alpha-benzoyl-L-Arg-p-nitroanilide (L-BApNA). The purified fraction showed three bands with proteolytic activity and molecular weights of 66,000, 71,000 and 91,000 (sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE)). Enzyme specificity assays were carried out using seven synthetic peptides containing 13 amino acid residues, but differing only on the 5th residue (K, R, Y, L, W or P). Peptide cleavage takes place only with amino acids K or R at the 5th position, which is typical of trypsin. The partially purified enzymes hydrolyzed casein and the synthetic trypsin substrates L-BApNA and N-alpha-p-tosyl-L-Arg methyl ester (L-TAME). Higher activity was observed at pH 8.5 and 35 degrees C when using L-BApNA as substrate and at pH 8.0 and 30 degrees C when using L-TAME. Maximum enzyme activity against L-BApNA was obtained with 20 mM CaCl2 in the reaction mixture. The partially purified enzymes showing trypsin activity were sensitive to inhibition by ethylenediaminetetraacetic acid (EDTA), phenylmethyl sulphonyl fluoride (PMSF), N-alpha-tosyl-L-lysine chloromethyl ketone (TLCK), benzamidine and aprotinin. Highest inhibition was obtained with TLCK and benzamidine. KM values obtained were 0.32 mM for L-BApNA and 52.5 microM for L-TAME.
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Affiliation(s)
- M G A Oliveira
- Departamento de Bioquímica e Biologia Molecular, Instituto de Biotecnologia Aplicada a Agropecuária (BIOAGRO), Universidade Federal de Viçosa, Viçosa, MG 36571-000, Brazil.
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23
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Tsybina TA, Dunaevsky YE, Belozersky MA, Zhuzhikov DP, Oppert B, Elpidina EN. Digestive proteinases of yellow mealworm (Tenebrio molitor) larvae: Purification and characterization of a trypsin-like proteinase. BIOCHEMISTRY (MOSCOW) 2005; 70:300-5. [PMID: 15823084 DOI: 10.1007/s10541-005-0115-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A new trypsin-like proteinase was purified to homogeneity from the posterior midgut of Tenebrio molitor larvae by ion-exchange chromatography on DEAE-Sephadex A-50 and gel filtration on Superdex-75. The isolated enzyme had molecular mass of 25.5 kD and pI 7.4. The enzyme was also characterized by temperature optimum at 55 degrees C, pH optimum at 8.5, and K(m) value of 0.04 mM (for hydrolysis of Bz-Arg-pNA). According to inhibitor analysis the enzyme is a trypsin-like serine proteinase stable within the pH range of 5.0-9.5. The enzyme hydrolyzes peptide bonds formed by Arg or Lys residues in the P1 position with a preference for relatively long peptide substrates. The N-terminal amino acid sequence, IVGGSSISISSVPXQIXLQY, shares 50-72% identity with other insect trypsin-like proteinases, and 44-50% identity to mammalian trypsins. The isolated enzyme is sensitive to inhibition by plant proteinase inhibitors and it can serve as a suitable target for control of digestion in this stored product pest.
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Affiliation(s)
- T A Tsybina
- Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow 119071, Russia
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Oliveira-Neto OB, Batista JAN, Rigden DJ, Fragoso RR, Silva RO, Gomes EA, Franco OL, Dias SC, Cordeiro CMT, Monnerat RG, Grossi-De-Sá MF. A diverse family of serine proteinase genes expressed in cotton boll weevil (Anthonomus grandis): implications for the design of pest-resistant transgenic cotton plants. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2004; 34:903-918. [PMID: 15350610 DOI: 10.1016/j.ibmb.2004.06.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2004] [Accepted: 06/01/2004] [Indexed: 05/24/2023]
Abstract
Fourteen different cDNA fragments encoding serine proteinases were isolated by reverse transcription-PCR from cotton boll weevil (Anthonomus grandis) larvae. A large diversity between the sequences was observed, with a mean pairwise identity of 22% in the amino acid sequence. The cDNAs encompassed 11 trypsin-like sequences classifiable into three families and three chymotrypsin-like sequences belonging to a single family. Using a combination of 5' and 3' RACE, the full-length sequence was obtained for five of the cDNAs, named Agser2, Agser5, Agser6, Agser10 and Agser21. The encoded proteins included amino acid sequence motifs of serine proteinase active sites, conserved cysteine residues, and both zymogen activation and signal peptides. Southern blotting analysis suggested that one or two copies of these serine proteinase genes exist in the A. grandis genome. Northern blotting analysis of Agser2 and Agser5 showed that for both genes, expression is induced upon feeding and is concentrated in the gut of larvae and adult insects. Reverse northern analysis of the 14 cDNA fragments showed that only two trypsin-like and two chymotrypsin-like were expressed at detectable levels. Under the effect of the serine proteinase inhibitors soybean Kunitz trypsin inhibitor and black-eyed pea trypsin/chymotrypsin inhibitor, expression of one of the trypsin-like sequences was upregulated while expression of the two chymotrypsin-like sequences was downregulated.
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Affiliation(s)
- Osmundo B Oliveira-Neto
- Embrapa Recursos Genéticos e Biotecnologia, S.A.I.N. Parque Estação Biológica, Final W3, Asa Norte, Brasilia, DF 70770-900, Brazil
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Wagner W, Möhrlen F, Schnetter W. Characterization of the proteolytic enzymes in the midgut of the European Cockchafer, Melolontha melolontha (Coleoptera: Scarabaeidae). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2002; 32:803-814. [PMID: 12044497 DOI: 10.1016/s0965-1748(01)00167-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In previous studies we showed that the resistance of the European Cockchafer, Melolontha melolontha, towards the Scarab specific Cry8C toxin of Bacillus thuringiensis japonensis strain Buibui is due to the complexity of proteinases in the midgut of the pest insect. In this study these proteinases were identified and characterized using a combination of synthetic substrates and specific inhibitors in zymograms, activity blots, and photometric/fluorometric assays. In the midgut juice three trypsin-like and three elastase-like serine proteinases are predominantly present. In addition, two metalloendoproteinases were detected. At least one of them is most likely to belong to the astacin family, proteinases which normally do not play a role in general protein digestion outside the decapod crustacean. Furthermore, a free aminopeptidase as well as a membrane-associated aminopeptidase, isolated from the brush boarder membrane vesicles (BBMV) of the midgut epithelium, were characterized.
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Affiliation(s)
- Wolfgang Wagner
- Institute of Zoology, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany.
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Roussel A, Mathieu M, Dobbs A, Luu B, Cambillau C, Kellenberger C. Complexation of two proteic insect inhibitors to the active site of chymotrypsin suggests decoupled roles for binding and selectivity. J Biol Chem 2001; 276:38893-8. [PMID: 11495915 DOI: 10.1074/jbc.m105707200] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The crystal structures of two homologous inhibitors (PMP-C and PMP-D2v) from the insect Locusta migratoria have been determined in complex with bovine alpha-chymotrypsin at 2.1- and 3.0-A resolution, respectively. PMP-C is a potent bovine alpha-chymotrypsin inhibitor whereas native PMP-D2 is a weak inhibitor of bovine trypsin. One unique mutation at the P1 position converts PMP-D2 into a potent bovine alpha-chymotrypsin inhibitor. The two peptides have a similar overall conformation, which consists of a triple-stranded antiparallel beta-sheet connected by three disulfide bridges, thus defining a novel family of serine protease inhibitors. They have in common the protease interaction site, which is composed of the classical protease binding loop (position P5 to P'4, corresponding to residues 26-34) and of an internal segment (residues 15-18), held together by two disulfide bridges. Structural divergences between the two inhibitors result in an additional interaction site between PMP-D2v (position P10 to P6, residues 21-25) and the residues 172-175 of alpha-chymotrypsin. This unusual interaction may be responsible for species selectivity. A careful comparison of data on bound and free inhibitors (from this study and previous NMR studies, respectively) suggests that complexation to the protease stabilizes the flexible binding loop (from P5 to P'4).
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Affiliation(s)
- A Roussel
- Architecture et Fonction de Macromolecules Biologiques, UMR-6098, CNRS et Universités d'Aix-Marseille I et II, 31 chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
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Ahsan MN, Watabe S. Kinetic and structural properties of two isoforms of trypsin isolated from the viscera of Japanese anchovy, Engraulis japonicus. JOURNAL OF PROTEIN CHEMISTRY 2001; 20:49-58. [PMID: 11330348 DOI: 10.1023/a:1011005104727] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Two isoforms of anchovy trypsin (aT-I and aT-II) were purified from the visceral extracts by (NH4)2SO4 fractionation followed by affinity chromatography, gel filtration, and ion-exchange chromatography. The homogeneity of the purified preparation was evidenced by both native- and SDS-PAGE, and further by gelatin zymography. Identities of aT-I and aT-II as trypsins were established by N-terminal amino acid sequencing, which matched exactly to the corresponding stretches of their respective amino acid sequences obtained by molecular cloning [Ahsan et al. (2000), Marine Biotechnol., in press]. Both isoforms were completely inhibited by serine protease inhibitors as well as by specific trypsin inhibitors. The purified anchovy trypsins showed considerably higher catalytic efficiencies (kcat/Km) than bovine trypsin as measured toward benzoyl-arginine p-nitroanilide (BAPA) and benzoyl-arginine ethyl ester (BAEE) at 25 degrees C; in particular, aT-II was 35 times more efficient than its mammalian counterpart against BAPA. This was due mainly to a dramatic decrease of Km values for anchovy trypsins, which are indicative of an evolutionary response toward increased substrate binding at suboptimal temperatures in the marine environment.
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Affiliation(s)
- M N Ahsan
- Laboratory of Aquatic Molecular Biology and Biotechnology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Japan
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