Relevant bibliographies by topics / Insect, protease, peptides

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Insect, protease, peptides'

Author: Grafiati
Published: 6 September 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Insect, protease, peptides.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Insect, protease, peptides"

1

COPLEY, S. Kathrin, M. Sheri ALM, A. David SCHOOLEY, and E. William COURCHESNE. "Expression, processing and secretion of a proteolytically-sensitive insect diuretic hormone by Saccharomyces cerevisiae requires the use of a yeast strain lacking genes encoding the Yap3 and Mkc7 endoproteases found in the secretory pathway." Biochemical Journal 330, no. 3 (March 15, 1998): 1333–40. http://dx.doi.org/10.1042/bj3301333.

Full text
Abstract:
A system is described for the heterologous expression of peptides in Saccharomyces cerevisiae. A synthetic gene encoding a precursor of the 41 amino acid Manduca sexta diuretic hormone (Mas-DH) was expressed at 0.8 mg/l purified peptide. A precursor of a mutant peptide of Mas-DH, Mas-DH[K22Q] was also expressed. The peptides were purified, then treated with peptidylglycine α-amidating enzyme to generate the α-amidated, mature, form of Mas-DH or Mas-DH[K22Q], which were biologically active. Successful expression of full-length Mas-DH+Gly depended upon the use of a protease-deficient yeast strain. In wild-type strains, Mas-DH+Gly was recovered only as proteolytic fragments, even in the presence of various protease inhibitors. Expression of Mas-DH+Gly in strains deficient in either the Mkc7 or the Yap3 protease reduced proteolysis, while no proteolysis of Mas-DH+Gly was detectable in a strain lacking both proteases. This protease-deficient strain may prove of general utility for expression of peptides. Analysis of recovered proteolytic fragments revealed a complex pattern of cleavage sites. Both the Yap3 and Mkc7 proteases preferred to cleave at a single Glu-Lys↓-Glu-Arg site. Analysis of secondary cleavage sites showed that Yap3 preferred to cleave after either Lys or Arg and Mkc7 after Lys. This paper is the first report on the in vivo activity and specificity of Yap3 and Mkc7 expressed at physiological levels.
APA, Harvard, Vancouver, ISO, and other styles
2

Deng, Yuping, James Gibbs, Igor Bačík, Angel Porgador, James Copeman, Paul Lehner, Bodo Ortmann, Peter Cresswell, Jack R. Bennink, and Jonathan W. Yewdell. "Assembly of MHC Class I Molecules with Biosynthesized Endoplasmic Reticulum-Targeted Peptides Is Inefficient in Insect Cells and Can Be Enhanced by Protease Inhibitors." Journal of Immunology 161, no. 4 (August 15, 1998): 1677–85. http://dx.doi.org/10.4049/jimmunol.161.4.1677.

Full text
Abstract:
Abstract To study the requirements for assembly of MHC class I molecules with antigenic peptides in the endoplasmic reticulum (ER), we studied Ag processing in insect cells. Insects lack a class I recognition system, and their cells therefore provide a “blank slate” for identifying the proteins that have evolved to facilitate assembly of class I molecules in vertebrate cells. H-2Kb heavy chain, mouse β2-microglobulin, and an ER-targeted version of a peptide corresponding to Ova257–264 were expressed in insect cells using recombinant vaccinia viruses. Cell surface expression of Kb-OVA257–264 complexes was quantitated using a recently described complex-specific mAb (25-D1.16). Relative to TAP-deficient human cells, insect cells expressed comparable levels of native, peptide-receptive cell surface Kb molecules, but generated cell surface Kb-OVA257–264 complexes at least 20-fold less efficiently from ER-targeted peptides. The inefficient assembly of Kb-OVA257–264 complexes in the ER of insect cells cannot be attributed solely to a requirement for human tapasin, since first, human cells lacking tapasin expressed endogenously synthesized Kb-OVA257–264 complexes at levels comparable to tapasin-expressing cells, and second, vaccinia virus-mediated expression of human tapasin in insect cells did not detectably enhance the expression of Kb-OVA257–264 complexes. The assembly of Kb-OVA257–264 complexes could be greatly enhanced in insect but not human cells by a nonproteasomal protease inhibitor. These findings indicate that insect cells lack one or more factors required for the efficient assembly of class I-peptide complexes in vertebrate cells and are consistent with the idea that the missing component acts to protect antigenic peptides or their immediate precursors from degradation.
APA, Harvard, Vancouver, ISO, and other styles
3

Caldas, C., A. Cherqui, A. Pereira, and N. Simões. "Purification and Characterization of an Extracellular Protease from Xenorhabdus nematophila Involved in Insect Immunosuppression." Applied and Environmental Microbiology 68, no. 3 (March 2002): 1297–304. http://dx.doi.org/10.1128/aem.68.3.1297-1304.2002.

Full text
Abstract:
ABSTRACT Xenorhabdus nematophila, a bacterium pathogenic for insects associated with the nematode Steinernema carpocapsae, releases high quantities of proteases, which may participate in the virulence against insects. Zymogram assays and cross-reactions of antibodies suggested that two distinct proteases were present. The major one, protease II, was purified and shown to have a molecular mass of 60 kDa and an estimated isoelectric point of 8.5. Protease II digested the chromogenic substrate N-tosyl-Gly-Pro-Arg-paranitroanilide (pNA) with V max and Km values of 0.0551 μM/min and 234 μM, respectively, and the substrate dl-Val-Leu-Arg-pNA with V max and Km values of 0.3830 μM/min and 429 μM, respectively. Protease II activity was inhibited 93% by Pefabloc SC and 45% by chymostatin. The optimum pH for protease II was 7, and the optimum temperature was 23°C. Proteolytic activity was reduced by 90% at 60°C for 10 min. Sequence analysis was performed on four internal peptides that resulted from the digestion of protease II. Fragments 29 and 45 are 75 and 68% identical to alkaline metalloproteinase produced by Pseudomonas aeruginosa. Fragment 29 is 79% identical to a metalloprotease of Erwinia amylovora and 75% identical to the protease C precursor of Erwinia chrysanthemi. Protease II showed no toxicity to hemocytes but destroyed antibacterial activity on the hemolymph of inoculated insects' larvae and reduced 97% of the cecropin A bacteriolytic activity.
APA, Harvard, Vancouver, ISO, and other styles
4

Pfrepper, Klaus-Ingmar, Hans-Richard Rackwitz, Martina Schnölzer, Hans Heid, Martin Löchelt, and Rolf M. Flügel. "Molecular Characterization of Proteolytic Processing of the Pol Proteins of Human Foamy Virus Reveals Novel Features of the Viral Protease." Journal of Virology 72, no. 9 (September 1, 1998): 7648–52. http://dx.doi.org/10.1128/jvi.72.9.7648-7652.1998.

Full text
Abstract:
ABSTRACT Spumaviruses, or foamy viruses, express a pol-specific transcript that codes for a Pol polyprotein that consists of the protease, reverse transcriptase, ribonuclease H, and the integrase domains. To delineate the proteolytic cleavage sites between the Pol subdomains, recombinant human foamy virus (HFV) Pol proteins were expressed, purified by affinity chromatography, and subjected to either HFV protease assays or autocatalytic processing. In control experiments, HFV protease-deficient mutant proteins in which the active site Asp was replaced by an Ala residue were used to rule out unspecific processing by nonviral proteases. Specific proteolytic cleavage products were isolated, and the cleavage sites were analyzed by amino acid sequencing. Peptides spanning the resulting cleavage sites were chemically synthesized and assayed with HFV protease, and the cleaved peptides were subjected to mass spectrometry. The cleavage site sequences obtained were in complete agreement with the amino-terminal sequences from amino acid sequencing of authentic cleavage products of the HFV Pol proteins. Analysis by fast-protein liquid chromatography of a short version of the active HFV protease revealed that the enzyme predominantly formed dimeric molecules.
APA, Harvard, Vancouver, ISO, and other styles
5

Lin, Ying-Chuan, Zachary Beck, Taekyu Lee, Van-Duc Le, Garrett M. Morris, Arthur J. Olson, Chi-Huey Wong, and John H. Elder. "Alteration of Substrate and Inhibitor Specificity of Feline Immunodeficiency Virus Protease." Journal of Virology 74, no. 10 (May 15, 2000): 4710–20. http://dx.doi.org/10.1128/jvi.74.10.4710-4720.2000.

Full text
Abstract:
ABSTRACT Feline immunodeficiency virus (FIV) protease is structurally very similar to human immunodeficiency virus (HIV) protease but exhibits distinct substrate and inhibitor specificities. We performed mutagenesis of subsite residues of FIV protease in order to define interactions that dictate this specificity. The I37V, N55M, M56I, V59I, and Q99V mutants yielded full activity. The I37V, N55M, V59I, and Q99V mutants showed a significant increase in activity against the HIV-1 reverse transcriptase/integrase and P2/nucleocapsid junction peptides compared with wild-type (wt) FIV protease. The I37V, V59I, and Q99V mutants also showed an increase in activity against two rapidly cleaved peptides selected by cleavage of a phage display library with HIV-1 protease. Mutations at Q54K, I98P, and L101I dramatically reduced activity. Mutants containing a I35D or I57G substitution showed no activity against either FIV or HIV substrates. FIV proteases all failed to cut HIV-1 matrix/capsid, P1/P6, P6/protease, and protease/reverse transcriptase junctions, indicating that none of the substitutions were sufficient to change the specificity completely. The I37V, N55M, M56I, V59I, and Q99V mutants, compared with wt FIV protease, all showed inhibitor specificity more similar to that of HIV-1 protease. The data also suggest that FIV protease prefers a hydrophobic P2/P2′ residue like Val over Asn or Glu, which are utilized by HIV-1 protease, and that S2/S2′ might play a critical role in distinguishing FIV and HIV-1 protease by specificity. The findings extend our observations regarding the interactions involved in substrate binding and aid in the development of broad-based inhibitors.
APA, Harvard, Vancouver, ISO, and other styles
6

Pfrepper, Klaus-Ingmar, Martin Löchelt, Hans-Richard Rackwitz, Martina Schnölzer, Hans Heid, and Rolf M. Flügel. "Molecular Characterization of Proteolytic Processing of the Gag Proteins of Human Spumavirus." Journal of Virology 73, no. 9 (September 1, 1999): 7907–11. http://dx.doi.org/10.1128/jvi.73.9.7907-7911.1999.

Full text
Abstract:
ABSTRACT Spumaviruses, or foamy viruses, express Gag proteins that are incompletely processed by the viral protease in cell cultures. To delineate the proteolytic cleavage sites between potential Gag subdomains, recombinant human spumaretrovirus (HSRV) Gag proteins of different lengths were expressed, purified by affinity chromatography, and subjected to HSRV protease assays. HSRV-specific proteolytic cleavage products were isolated and characterized by Western blotting. Peptides spanning potential cleavage sites, as deduced from the sizes of the proteolytic cleavage products, were chemically synthesized and assayed with HSRV protease. The cleaved peptides were then subjected to mass spectrometry. In control experiments, HSRV protease-deficient mutant proteins were used to rule out unspecific processing by nonviral proteases. The cleavage site junctions identified and the calculated sizes of the cleavage products were in agreement with those of the authentic cleavage products of the HSRV Gag proteins detectable in viral proteins from purified HSRV particles and in virus-infected cells. The biological significance of the data was confirmed by mutational analysis of the cleavage sites in a recombinant Gag protein and in the context of the infectious HSRV DNA provirus.
APA, Harvard, Vancouver, ISO, and other styles
7

SIMONET, Gert, Bert BREUGELMANS, Paul PROOST, Ilse CLAEYS, Jozef VAN DAMME, Arnold DE LOOF, and Jozef VANDEN BROECK. "Characterization of two novel pacifastin-like peptide precursor isoforms in the desert locust (Schistocerca gregaria): cDNA cloning, functional analysis and real-time RT-PCR gene expression studies." Biochemical Journal 388, no. 1 (May 10, 2005): 281–89. http://dx.doi.org/10.1042/bj20041414.

Full text
Abstract:
In the last decade, a new serine protease inhibitor family has been described in arthropods. Eight members of the family were purified from locusts and share a conserved cysteine array (Cys-Xaa9–12-Cys-Asn-Xaa-Cys-Xaa-Cys-Xaa2–3-Gly-Xaa3–6-Cys-Thr-Xaa3-Cys) with nine inhibitory domains of the light chain of the crayfish protease inhibitor, pacifastin (PLDs; pacifastin light chain domains). Using cDNA cloning, several pacifastin-related precursors have been identified, encoding additional PLD-related peptides in different insect species. In the present study, two isoforms of a novel pacifastin-related precursor (SGPP-4) have been identified in the desert locust, predicting the previously identified SGPI-5 (Schistocerca gregaria PLD-related inhibitor-5) peptide and two novel PLD-related peptide sequences. One novel peptide (SGPI-5A) was synthesized chemically, and its inhibitory activity was assessed in vitro. Although proteases from a locust midgut extract were very sensitive to SGPI-5A, the same peptide proved to be a relatively poor inhibitor of bovine trypsin. By an in silico datamining approach, a novel pacifastin-related precursor with seven PLD-related domains was identified in the mosquito, Aedes aegypti. As in other insect pacifastin-related precursors, the Aedes precursor showed a particular domain architecture that is not encountered in other serine protease inhibitor families. Finally, a comparative real-time RT-PCR analysis of SGPP-4 transcripts in different tissues of isolated- (solitarious) and crowded-reared (gregarious) locusts was performed. This showed that SGPP-4 mRNA levels are higher in the brain, testes and fat body of gregarious males than of solitarious males. These results have been compared with data from a similar study on SGPP-1–3 transcripts and discussed with respect to a differential regulation of serine-protease-dependent pathways as a possible mechanism underlying locust phase polymorphism.
APA, Harvard, Vancouver, ISO, and other styles
8

Beck, Zachary Q., Ying-Chuan Lin, and John H. Elder. "Molecular Basis for the Relative Substrate Specificity of Human Immunodeficiency Virus Type 1 and Feline Immunodeficiency Virus Proteases." Journal of Virology 75, no. 19 (October 1, 2001): 9458–69. http://dx.doi.org/10.1128/jvi.75.19.9458-9469.2001.

Full text
Abstract:
ABSTRACT We have used a random hexamer phage library to delineate similarities and differences between the substrate specificities of human immunodeficiency virus type 1 (HIV-1) and feline immunodeficiency virus (FIV) proteases (PRs). Peptide sequences were identified that were specifically cleaved by each protease, as well as sequences cleaved equally well by both enzymes. Based on amino acid distinctions within the P3-P3′ region of substrates that appeared to correlate with these cleavage specificities, we prepared a series of synthetic peptides within the framework of a peptide sequence cleaved with essentially the same efficiency by both HIV-1 and FIV PRs, Ac-KSGVF↓VVNGLVK-NH2 (arrow denotes cleavage site). We used the resultant peptide set to assess the influence of specific amino acid substitutions on the cleavage characteristics of the two proteases. The findings show that when Asn is substituted for Val at the P2 position, HIV-1 PR cleaves the substrate at a much greater rate than does FIV PR. Likewise, Glu or Gln substituted for Val at the P2′ position also yields peptides specifically susceptible to HIV-1 PR. In contrast, when Ser is substituted for Val at P1′, FIV PR cleaves the substrate at a much higher rate than does HIV-1 PR. In addition, Asn or Gln at the P1 position, in combination with an appropriate P3 amino acid, Arg, also strongly favors cleavage by FIV PR over HIV PR. Structural analysis identified several protease residues likely to dictate the observed specificity differences. Interestingly, HIV PR Asp30 (Ile-35 in FIV PR), which influences specificity at the S2 and S2′ subsites, and HIV-1 PR Pro-81 and Val-82 (Ile-98 and Gln-99 in FIV PR), which influence specificity at the S1 and S1′ subsites, are residues which are often involved in development of drug resistance in HIV-1 protease. The peptide substrate KSGVF↓VVNGK, cleaved by both PRs, was used as a template for the design of a reduced amide inhibitor, Ac-GSGVFΨ(CH2NH)VVNGL-NH2. This compound inhibited both FIV and HIV-1 PRs with approximately equal efficiency. These findings establish a molecular basis for distinctions in substrate specificity between human and feline lentivirus PRs and offer a framework for development of efficient broad-based inhibitors.
APA, Harvard, Vancouver, ISO, and other styles
9

Zhang, T. T., G. C. Zhang, F. F. Zeng, C. Y. Liu, and J. J. Mao. "Insulin-like peptides regulate vitellogenesis and oviposition in the green lacewing, Chrysopa septempunctata." Bulletin of Entomological Research 107, no. 2 (August 30, 2016): 148–54. http://dx.doi.org/10.1017/s0007485316000742.

Full text
Abstract:
AbstractInsulin-like peptides (ILPs) act through a conserved insulin signaling pathway and play crucial roles in insect metabolism, growth, reproduction, and aging. Application of bovine insulin is able to increase vitellogenin (Vg) mRNA and protein levels in female insects. Here, we first show that injection of bovine insulin into previtellogenic Chrysopa septempunctata female adults promoted ovarian growth, increased Vg protein abundance, elevated reproductive performance, and enhanced protease activity. These data suggested that ILPs play crucial roles in reproductive regulation of the green lacewing, C. septempunctata.
APA, Harvard, Vancouver, ISO, and other styles
10

You, Liwen, Daniel Garwicz, and Thorsteinn Rögnvaldsson. "Comprehensive Bioinformatic Analysis of the Specificity of Human Immunodeficiency Virus Type 1 Protease." Journal of Virology 79, no. 19 (October 1, 2005): 12477–86. http://dx.doi.org/10.1128/jvi.79.19.12477-12486.2005.

Full text
Abstract:
ABSTRACT Rapidly developing viral resistance to licensed human immunodeficiency virus type 1 (HIV-1) protease inhibitors is an increasing problem in the treatment of HIV-infected individuals and AIDS patients. A rational design of more effective protease inhibitors and discovery of potential biological substrates for the HIV-1 protease require accurate models for protease cleavage specificity. In this study, several popular bioinformatic machine learning methods, including support vector machines and artificial neural networks, were used to analyze the specificity of the HIV-1 protease. A new, extensive data set (746 peptides that have been experimentally tested for cleavage by the HIV-1 protease) was compiled, and the data were used to construct different classifiers that predicted whether the protease would cleave a given peptide substrate or not. The best predictor was a nonlinear predictor using two physicochemical parameters (hydrophobicity, or alternatively polarity, and size) for the amino acids, indicating that these properties are the key features recognized by the HIV-1 protease. The present in silico study provides new and important insights into the workings of the HIV-1 protease at the molecular level, supporting the recent hypothesis that the protease primarily recognizes a conformation rather than a specific amino acid sequence. Furthermore, we demonstrate that the presence of 1 to 2 lysine residues near the cleavage site of octameric peptide substrates seems to prevent cleavage efficiently, suggesting that this positively charged amino acid plays an important role in hindering the activity of the HIV-1 protease.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Insect, protease, peptides"

1

Jamriska, Lubomira. "Characterisation of dipeptidyl peptidase I of the Asian blood fluke, Schistosoma japonicum." Thesis, Queensland University of Technology, 2000.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Insect, protease, peptides"

1

Law, John H., Peter E. Dunn, and Karl J. Kramer. "Insect Proteases and Peptidases." In Advances in Enzymology - and Related Areas of Molecular Biology, 389–425. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2006. http://dx.doi.org/10.1002/9780470122907.ch5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Beatriz Meriño-Cabrera, Yaremis, and Maria Goreti de Almeida Oliveira. "Trypsins: Structural Characterization and Inhibition Focus in Insects." In Hydrolases [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.102632.

Full text
Abstract:
Serine proteases are considered the main class of protein digestive enzymes present in the midgut of many lepidopteran species and are the focus of the review in this chapter. Among them, trypsin and chymotrypsin are the most studied and participate in a great diversity of physiological processes that include, in addition to digestion, activation of specific proteins, such as in the coagulation cascades, in the immune system of insects and plants, in the development and production of biologically active peptides, in signal transduction, hormone activation, and development. In this chapter, a review was made of the structural characteristics of trypsins, specifically of Lepidoptera insects, main experimental and theoretical techniques for the study of their function and structure, and interaction with other proteins and ligands as protease inhibitors. Finally, it was described how this type of hydrolases can be a focus of inhibition in pests to the detriment of the development and death of the target insect. Until now, the main strategies of agricultural crop management, especially of large crops, consist of the use of inorganic pesticides and transgenic cultivars containing Bacillus thuringiensis toxins. Therefore, new and ecologically friendly strategies are necessary, such as the use of protease inhibitors.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Insect, protease, peptides"

1

Lopez, J. A., D. W. Chung, K. Fujikawa, F. S. Hagen, T. Papavannopoulou, and G. J. Roth. "MOLECULAR CLONING OF HUMAN PLATELET GLYCOPROTEIN Ib." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642927.

Full text
Abstract:
Glycoprotein Ib (GPIb) mediates von Willebrand factor-dependent platelet adhesion and participates in the resulting platelet activation process. In the present investigation, the primary structure of human platelet GPIb was studied. GPIb and its proteolytic fragment glycocalicin were purified to near homogeneity from human platelets by affinity chromatography using wheat germ agglutinin and anti-GPIb monoclonal antibody (D. Nugent, University of Washington) coupled to Sepharose. GPIba chain, β chain, and glycocalicin were isolated, reduced and carboxymethylated, and then fragmented by trypsin and S. aureus V8 protease. Peptides were isolated by HPLC and subjected to amino acid sequence analysis. Approximately 200 amino acid residues were identified. Affinity purified rabbit antibodies directed against the a chain, the ft chain, and glycocalicin were prepared and shown to be monospecific by Western blot analysis. Total RNA was prepared from human erythroleukemia cells grown in the presence of phorbol acetate. Poly(A)+ RNA was selected and used to prepare a cDNA library in λgt11. The library was screened with [125]I-labeled polyclonal antibody to glycocalicin. The clone with the largest cDNA insert was sequenced and shown to code for amino acid sequences corresponding to those determined by Edman degradation of glycocalicin. The predicted amino acid sequence contains at least six tandem repeats of 24 amino acids that are highly homologous with 13 repeats present in leucine rich α2 glycoprotein of human plasma. Another region in the protein contains a second repeat rich in threonine and serine, which shows some homology to a 9 amino acid repeat in the connecting region of human factor V. This region is probably the major site of attachment of clusters of O-linked carbohydrate in GPIbα. These results indicate that human platelet glycoprotein Ibα has a multi-domain structure composed of a number of repetitive sequences. Supported in part by grants from the American Heart Association, Robert Wood Johnson Foundation, Veterans Administration, and National Institutes of Health.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Insect, protease, peptides' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography