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Karl J Kramer - One of the best experts on this subject based on the ideXlab platform.
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tyrosine metabolism for Insect Cuticle pigmentation and sclerotization
2016Co-Authors: Yasuyuki Arakane, Tsunaki Asano, Karl J KramerAbstract:Pigmentation or body color patterns in Insects quite often differ not only between species but also in different stages of development and in different body regions of a single species. Body coloration plays physiologically and ecologically important roles as for instance in species recognition and communication, courtship/mate selection, mimicry, crypsis, warning, prey-predator/parasite interactions, and resistance to temperature, desiccation and absorbs or reflects harmful ultraviolet radiation. Many kinds of pigment molecules and structural colors contribute to the diversity of body coloration in Insects. Recent studies have elucidated some of the genetic and molecular biological mechanisms underlying pigment biosynthesis. This chapter focuses on the pigments derived from the amino acid tyrosine. The tyrosine-mediated Cuticle tanning pathway is responsible for production of melanins and other pigments derived from 3,4-dihydroxyphenylalanine (DOPA) and dopamine as well as from N-acyldopamines. The N-acylated dopamines, in addition, are oxidized by the phenoloxidase laccase 2 to form quinones and quinone methides, which then undergo cross-linking reactions with cuticular proteins (CPs) for Cuticle sclerotization. We review the regulation and functional importance and also the diversity of the genes involved in this pathway. The unique localization and cross-linking of specific CPs for morphology and ultrastructure of the exoskeleton are also discussed.
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cuticular protein with a low complexity sequence becomes cross linked during Insect Cuticle sclerotization and is required for the adult molt
Scientific Reports, 2015Co-Authors: Neal T Dittmer, Karl J Kramer, Michael R Kanost, Subbaratnam Muthukrishnan, Yasuyuki ArakaneAbstract:In the Insect Cuticle, structural proteins (CPs) and the polysaccharide chitin are the major components. It has been hypothesized that CPs are cross-linked to other CPs and possibly to chitin by quinones or quinone methides produced by the laccase2-mediated oxidation of N-acylcatechols. In this study we investigated functions of TcCP30, the third most abundant CP in protein extracts of elytra (wing covers) from Tribolium castaneum adults. The mature TcCP30 protein has a low complexity and highly polar amino acid sequence. TcCP30 is localized with chitin in horizontal laminae and vertically oriented columnar structures in rigid Cuticles, but not in soft and membranous Cuticles. Immunoblot analysis revealed that TcCP30 undergoes laccase2-mediated cross-linking during Cuticle maturation in vivo, a process confirmed in vitro using recombinant rTcCP30. We identified TcCPR27 and TcCPR18, the two most abundant proteins in the elytra, as putative cross-linking partners of TcCP30. RNAi for the TcCP30 gene had no effect on larval and pupal growth and development. However, during adult eclosion, ~70% of the adults were unable to shed their exuvium and died. These results support the hypothesis that TcCP30 plays an integral role as a cross-linked structural protein in the formation of lightweight rigid Cuticle of the beetle.
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model reactions for Insect Cuticle sclerotization participation of amino groups in the cross linking of manduca sexta Cuticle protein mscp36
Insect Biochemistry and Molecular Biology, 2010Co-Authors: Richard J Suderman, Karl J Kramer, Neal T Dittmer, Michael R KanostAbstract:Current theories of sclerotization center on protein cross-linking and dehydration as major factors in the hardening and stability of the Insect Cuticle. Several studies have reported the identification of catecholamino acid adducts from sclerotizing Cuticle involving histidine, lysine, and tyrosine, though there have been no reports of a catechol linked between two amino acid residues. Previously, we reported an in vitro model system for sclerotization and observed that stable protein oligomers were formed, presumably through cross-links with oxidized catecholamines [Insect Biochem. Mol. Biol. (2006) 36, 353e365]. Using site-directed mutagenesis we created a mutant lacking histidine, rMsCP36(H65A/H178A), to investigate the possible involvement of the two histidine residues of MsCP36 in cross-linking. Surprisingly, this alteration had little ornoeffecton the formation of proteinoligomers as determined bySDS-PAGEanalysis. Blockingof the freeaminogroupsinlysylsidechainsandtheamino-terminus bysuccinylationdiminished, but did not eliminate, cross-linking of either rMsCP36 or rMsCP36(H65A/H178A). We also examined the possibility that cross-linking was due to intermolecular dityrosine linkages. Immunoblot analysis utilizing a monoclonal antibody known to recognize peptidyl dityrosine indicated that dityrosyl cross-links were present. Taken together, these results indicate that lysyl residues are important for the cross-linking of the Cuticle protein rMsCP36, but that additional residues other than histidine can also contribute. 2010 Elsevier Ltd. All rights reserved.
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erratumerratum to model reactions for Insect Cuticle sclerotization cross linking of recombinant cuticular proteins upon their laccase catalyzed oxidative conjugation with catechols Insect biochemistry and molecular biology 36 2006 353 365
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:Erratum to ‘‘Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols’’ [Insect Biochemistry and Molecular Biology 36 (2006) 353–365] Richard J. Suderman, Neal T. Dittmer, Michael R. Kanost , Karl J. Kramer Department of Biochemistry, 103 Willard Hall, Kansas State University, Manhattan, KS 66506-3706, USA Grain Marketing and Production Research Center, Agricultural Research Service, US Department of Agriculture, Manhattan, KS 66506-2736, USA
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ErratumErratum to “Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols”: [Insect Biochemistry and Molecular Biology 36 (2006) 353–365]
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:Erratum to ‘‘Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols’’ [Insect Biochemistry and Molecular Biology 36 (2006) 353–365] Richard J. Suderman, Neal T. Dittmer, Michael R. Kanost , Karl J. Kramer Department of Biochemistry, 103 Willard Hall, Kansas State University, Manhattan, KS 66506-3706, USA Grain Marketing and Production Research Center, Agricultural Research Service, US Department of Agriculture, Manhattan, KS 66506-2736, USA
Michael R Kanost - One of the best experts on this subject based on the ideXlab platform.
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self assembled coacervates of chitosan and an Insect Cuticle protein containing a rebers riddiford motif
Biomacromolecules, 2018Co-Authors: Coleman M Vaclaw, Patricia A Sprouse, Neal T Dittmer, Saba Ghazvini, Russell C Middaugh, Michael R Kanost, Stevin H Gehrke, Prajnaparamita DharAbstract:The interactions among biomacromolecules within Insect Cuticle may offer new motifs for biomimetic material design. CPR27 is an abundant protein in the rigid Cuticle of the elytron from Tribolium castaneum. CPR27 contains the Rebers–Riddiford (RR) motif, which is hypothesized to bind chitin. In this study, active magnetic microrheology coupled with microscopy and protein particle analysis techniques were used to correlate alterations in the viscosity of chitosan solutions with changes in solution microstructure. Addition of CPR27 to chitosan solutions led to a 3-fold drop in viscosity. This change was accompanied by the presence of micrometer-sized coacervate particles in solution. Coacervate formation had a strong dependence on chitosan concentration. Analysis showed the existence of a critical CPR27 concentration beyond which a significant increase in particle count was observed. These effects were not observed when a non-RR cuticular protein, CP30, was tested, providing evidence of a structure–function...
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cuticular protein with a low complexity sequence becomes cross linked during Insect Cuticle sclerotization and is required for the adult molt
Scientific Reports, 2015Co-Authors: Neal T Dittmer, Karl J Kramer, Michael R Kanost, Subbaratnam Muthukrishnan, Yasuyuki ArakaneAbstract:In the Insect Cuticle, structural proteins (CPs) and the polysaccharide chitin are the major components. It has been hypothesized that CPs are cross-linked to other CPs and possibly to chitin by quinones or quinone methides produced by the laccase2-mediated oxidation of N-acylcatechols. In this study we investigated functions of TcCP30, the third most abundant CP in protein extracts of elytra (wing covers) from Tribolium castaneum adults. The mature TcCP30 protein has a low complexity and highly polar amino acid sequence. TcCP30 is localized with chitin in horizontal laminae and vertically oriented columnar structures in rigid Cuticles, but not in soft and membranous Cuticles. Immunoblot analysis revealed that TcCP30 undergoes laccase2-mediated cross-linking during Cuticle maturation in vivo, a process confirmed in vitro using recombinant rTcCP30. We identified TcCPR27 and TcCPR18, the two most abundant proteins in the elytra, as putative cross-linking partners of TcCP30. RNAi for the TcCP30 gene had no effect on larval and pupal growth and development. However, during adult eclosion, ~70% of the adults were unable to shed their exuvium and died. These results support the hypothesis that TcCP30 plays an integral role as a cross-linked structural protein in the formation of lightweight rigid Cuticle of the beetle.
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model reactions for Insect Cuticle sclerotization participation of amino groups in the cross linking of manduca sexta Cuticle protein mscp36
Insect Biochemistry and Molecular Biology, 2010Co-Authors: Richard J Suderman, Karl J Kramer, Neal T Dittmer, Michael R KanostAbstract:Current theories of sclerotization center on protein cross-linking and dehydration as major factors in the hardening and stability of the Insect Cuticle. Several studies have reported the identification of catecholamino acid adducts from sclerotizing Cuticle involving histidine, lysine, and tyrosine, though there have been no reports of a catechol linked between two amino acid residues. Previously, we reported an in vitro model system for sclerotization and observed that stable protein oligomers were formed, presumably through cross-links with oxidized catecholamines [Insect Biochem. Mol. Biol. (2006) 36, 353e365]. Using site-directed mutagenesis we created a mutant lacking histidine, rMsCP36(H65A/H178A), to investigate the possible involvement of the two histidine residues of MsCP36 in cross-linking. Surprisingly, this alteration had little ornoeffecton the formation of proteinoligomers as determined bySDS-PAGEanalysis. Blockingof the freeaminogroupsinlysylsidechainsandtheamino-terminus bysuccinylationdiminished, but did not eliminate, cross-linking of either rMsCP36 or rMsCP36(H65A/H178A). We also examined the possibility that cross-linking was due to intermolecular dityrosine linkages. Immunoblot analysis utilizing a monoclonal antibody known to recognize peptidyl dityrosine indicated that dityrosyl cross-links were present. Taken together, these results indicate that lysyl residues are important for the cross-linking of the Cuticle protein rMsCP36, but that additional residues other than histidine can also contribute. 2010 Elsevier Ltd. All rights reserved.
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erratumerratum to model reactions for Insect Cuticle sclerotization cross linking of recombinant cuticular proteins upon their laccase catalyzed oxidative conjugation with catechols Insect biochemistry and molecular biology 36 2006 353 365
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:Erratum to ‘‘Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols’’ [Insect Biochemistry and Molecular Biology 36 (2006) 353–365] Richard J. Suderman, Neal T. Dittmer, Michael R. Kanost , Karl J. Kramer Department of Biochemistry, 103 Willard Hall, Kansas State University, Manhattan, KS 66506-3706, USA Grain Marketing and Production Research Center, Agricultural Research Service, US Department of Agriculture, Manhattan, KS 66506-2736, USA
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ErratumErratum to “Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols”: [Insect Biochemistry and Molecular Biology 36 (2006) 353–365]
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:Erratum to ‘‘Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols’’ [Insect Biochemistry and Molecular Biology 36 (2006) 353–365] Richard J. Suderman, Neal T. Dittmer, Michael R. Kanost , Karl J. Kramer Department of Biochemistry, 103 Willard Hall, Kansas State University, Manhattan, KS 66506-3706, USA Grain Marketing and Production Research Center, Agricultural Research Service, US Department of Agriculture, Manhattan, KS 66506-2736, USA
Neal T Dittmer - One of the best experts on this subject based on the ideXlab platform.
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self assembled coacervates of chitosan and an Insect Cuticle protein containing a rebers riddiford motif
Biomacromolecules, 2018Co-Authors: Coleman M Vaclaw, Patricia A Sprouse, Neal T Dittmer, Saba Ghazvini, Russell C Middaugh, Michael R Kanost, Stevin H Gehrke, Prajnaparamita DharAbstract:The interactions among biomacromolecules within Insect Cuticle may offer new motifs for biomimetic material design. CPR27 is an abundant protein in the rigid Cuticle of the elytron from Tribolium castaneum. CPR27 contains the Rebers–Riddiford (RR) motif, which is hypothesized to bind chitin. In this study, active magnetic microrheology coupled with microscopy and protein particle analysis techniques were used to correlate alterations in the viscosity of chitosan solutions with changes in solution microstructure. Addition of CPR27 to chitosan solutions led to a 3-fold drop in viscosity. This change was accompanied by the presence of micrometer-sized coacervate particles in solution. Coacervate formation had a strong dependence on chitosan concentration. Analysis showed the existence of a critical CPR27 concentration beyond which a significant increase in particle count was observed. These effects were not observed when a non-RR cuticular protein, CP30, was tested, providing evidence of a structure–function...
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cuticular protein with a low complexity sequence becomes cross linked during Insect Cuticle sclerotization and is required for the adult molt
Scientific Reports, 2015Co-Authors: Neal T Dittmer, Karl J Kramer, Michael R Kanost, Subbaratnam Muthukrishnan, Yasuyuki ArakaneAbstract:In the Insect Cuticle, structural proteins (CPs) and the polysaccharide chitin are the major components. It has been hypothesized that CPs are cross-linked to other CPs and possibly to chitin by quinones or quinone methides produced by the laccase2-mediated oxidation of N-acylcatechols. In this study we investigated functions of TcCP30, the third most abundant CP in protein extracts of elytra (wing covers) from Tribolium castaneum adults. The mature TcCP30 protein has a low complexity and highly polar amino acid sequence. TcCP30 is localized with chitin in horizontal laminae and vertically oriented columnar structures in rigid Cuticles, but not in soft and membranous Cuticles. Immunoblot analysis revealed that TcCP30 undergoes laccase2-mediated cross-linking during Cuticle maturation in vivo, a process confirmed in vitro using recombinant rTcCP30. We identified TcCPR27 and TcCPR18, the two most abundant proteins in the elytra, as putative cross-linking partners of TcCP30. RNAi for the TcCP30 gene had no effect on larval and pupal growth and development. However, during adult eclosion, ~70% of the adults were unable to shed their exuvium and died. These results support the hypothesis that TcCP30 plays an integral role as a cross-linked structural protein in the formation of lightweight rigid Cuticle of the beetle.
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model reactions for Insect Cuticle sclerotization participation of amino groups in the cross linking of manduca sexta Cuticle protein mscp36
Insect Biochemistry and Molecular Biology, 2010Co-Authors: Richard J Suderman, Karl J Kramer, Neal T Dittmer, Michael R KanostAbstract:Current theories of sclerotization center on protein cross-linking and dehydration as major factors in the hardening and stability of the Insect Cuticle. Several studies have reported the identification of catecholamino acid adducts from sclerotizing Cuticle involving histidine, lysine, and tyrosine, though there have been no reports of a catechol linked between two amino acid residues. Previously, we reported an in vitro model system for sclerotization and observed that stable protein oligomers were formed, presumably through cross-links with oxidized catecholamines [Insect Biochem. Mol. Biol. (2006) 36, 353e365]. Using site-directed mutagenesis we created a mutant lacking histidine, rMsCP36(H65A/H178A), to investigate the possible involvement of the two histidine residues of MsCP36 in cross-linking. Surprisingly, this alteration had little ornoeffecton the formation of proteinoligomers as determined bySDS-PAGEanalysis. Blockingof the freeaminogroupsinlysylsidechainsandtheamino-terminus bysuccinylationdiminished, but did not eliminate, cross-linking of either rMsCP36 or rMsCP36(H65A/H178A). We also examined the possibility that cross-linking was due to intermolecular dityrosine linkages. Immunoblot analysis utilizing a monoclonal antibody known to recognize peptidyl dityrosine indicated that dityrosyl cross-links were present. Taken together, these results indicate that lysyl residues are important for the cross-linking of the Cuticle protein rMsCP36, but that additional residues other than histidine can also contribute. 2010 Elsevier Ltd. All rights reserved.
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erratumerratum to model reactions for Insect Cuticle sclerotization cross linking of recombinant cuticular proteins upon their laccase catalyzed oxidative conjugation with catechols Insect biochemistry and molecular biology 36 2006 353 365
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:Erratum to ‘‘Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols’’ [Insect Biochemistry and Molecular Biology 36 (2006) 353–365] Richard J. Suderman, Neal T. Dittmer, Michael R. Kanost , Karl J. Kramer Department of Biochemistry, 103 Willard Hall, Kansas State University, Manhattan, KS 66506-3706, USA Grain Marketing and Production Research Center, Agricultural Research Service, US Department of Agriculture, Manhattan, KS 66506-2736, USA
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ErratumErratum to “Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols”: [Insect Biochemistry and Molecular Biology 36 (2006) 353–365]
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:Erratum to ‘‘Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols’’ [Insect Biochemistry and Molecular Biology 36 (2006) 353–365] Richard J. Suderman, Neal T. Dittmer, Michael R. Kanost , Karl J. Kramer Department of Biochemistry, 103 Willard Hall, Kansas State University, Manhattan, KS 66506-3706, USA Grain Marketing and Production Research Center, Agricultural Research Service, US Department of Agriculture, Manhattan, KS 66506-2736, USA
David Taylor - One of the best experts on this subject based on the ideXlab platform.
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repair of microdamage caused by cyclic loading in Insect Cuticle
Journal of Experimental Zoology, 2020Co-Authors: Maeve Oneill, David TaylorAbstract:: It is well known that repeated loading cycles can reduce the strength of a material and cause eventual failure by the gradual build-up of damage. Previous work has shown that mammalian bone is able to extend its life almost indefinitely by continuously repairing microdamage, preventing the development of macroscopic cracks. However, no study has been conducted until now to investigate repair of microdamage in any other biological material. We applied cyclic bending loads to the hind tibiae of desert locusts (Schistocerca gregaria). We observed a significant decrease in the elastic stiffness (Young's modulus) of the Cuticle during the five applied loading cycles, indicating that microdamage had been induced. The tibiae were then left to rest for various time periods: 1 hr, 24 hr, 1 week, and 4 weeks. When tested again after up to 24 hr, there was still a significant decrease in stiffness, showing that some microdamage remained. However, in the samples left for 1 week or 4 weeks before retesting, this decrease in stiffness had disappeared, indicating that the microdamage had been repaired. This is the first ever indication that Insects are capable of repairing microdamage. It is a highly significant finding-Insects such as locusts rely on the stiffness and strength of their hind legs for jumping. This study suggests that, within a time period of order of a few days, the Insect can fully restore the mechanical function of an overloaded leg and thus return to normal activities.
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age related responses to injury and repair in Insect Cuticle
The Journal of Experimental Biology, 2019Co-Authors: Maeve Oneill, Diego Delandro, David TaylorAbstract:ABSTRACT We evaluated the ability of female adult desert locusts (Schistocerca gregaria) to repair injuries to their exoskeletons and restore mechanical strength over the course of their natural life. We discovered that younger Insects are more capable of repairing injuries, displaying no significant decreases in failure strength, stiffness or bending moment to failure after 3 weeks of repair. Older Insects, in contrast, were only capable of repairing to ∼70% of their original strength. Both older and younger Insects carry out targeted deposition to repair injuries. We also examined different mechanisms of failure, and we discovered that the Cuticle of older Insects is more susceptible to crack growth due to a large decrease in fracture toughness with age, making them more sensitive to scalpel cuts and punctures. The biological mechanisms that drive these changes are still under investigation.
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wing cross veins an efficient biomechanical strategy to mitigate fatigue failure of Insect Cuticle
Biomechanics and Modeling in Mechanobiology, 2017Co-Authors: Stanislav N Gorb, H Rajabi, A Darvizeh, P Bazargan, A Pourbabaei, Sh Eshghi, David TaylorAbstract:Locust wings are able to sustain millions of cycles of mechanical loading during the lifetime of the Insect. Previous studies have shown that cross veins play an important role in delaying crack propagation in the wings. Do cross veins thus also influence the fatigue behaviour of the wings? Since many important fatigue parameters are not experimentally accessible in a small biological sample, here we use the finite element (FE) method to address this question numerically. Our FE model combines a linear elastic material model, a direct cyclic approach and the Paris law and shows results which are in very good agreement with previously reported experimental data. The obtained results of our study show that cross veins indeed enhance the durability of the wings by temporarily stopping cracks. The cross veins further distribute the stress over a larger area and therefore minimize stress concentrations. In addition, our work indicates that locust hind wings have an endurance limit of about 40% of the ultimate tensile strength of the wing material, which is comparable to many engineering materials. The comparison of the results of the computational study with predictions of two most commonly used fatigue failure criteria further indicates that the Goodman criterion can be used to roughly predict the failure of the Insect wing. The methodological framework presented in our study could provide a basis for future research on fatigue of Insect Cuticle and other biological composite structures.
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damage repair and regeneration in Insect Cuticle the story so far and possibilities for the future
Arthropod Structure & Development, 2017Co-Authors: Eoin Parle, Janhenning Dirks, David TaylorAbstract:Abstract The exoskeleton of an Insect can contain countless specializations across an individual, across developmental stages, and across the class Insecta. Hence, the exoskeleton's building material Cuticle must perform a vast variety of functions. Cuticle displays a wide range of material properties which are determined by several known factors: the amount and orientation of the chitin fibres, the constituents and degree of cross-linking and hydration of the protein matrix, the relative amounts of exo- and endoCuticle, and the shape of the structures themselves. In comparison to other natural materials such as wood and mammal bone, relatively few investigations into the mechanical properties of Insect Cuticle have been carried out. Of these, very few have focussed on the need for repair and its effectiveness at restoring mechanical stability to the Cuticle. Insect body parts are often subject to prolonged repeated cyclic loads when running and flying, as well as more extreme “emergency” behaviours necessary for survival such as jumping, wedging (squeezing through small holes) and righting (when overturned). What effects have these actions on the Cuticle itself? How close to the limits of failure does an Insect push its body parts? Can an Insect recover from minor or major damage to its exoskeleton “bones”? No current research has answered these questions conclusively.
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fatigue of Insect Cuticle
The Journal of Experimental Biology, 2013Co-Authors: Janhenning Dirks, Eoin Parle, David TaylorAbstract:Many parts of the Insect exoskeleton experience repeated cyclic loading. Although the Cuticle of Insects and other arthropods is the second most common natural composite material in the world, so far nothing is known about its fatigue properties, despite the fact that fatigue undoubtedly limits the durability of body parts in vivo . For the first time, we here present experimental fatigue data of Insect Cuticle. Using force-controlled cyclic loading, we determined the number of cycles to failure for hind legs (tibiae) and hind wings of the locust Schistocerca gregaria , as a function of the applied cyclic stress. Our results show that, although both are made from Cuticle, these two body parts behave very differently. Wing samples showed a large fatigue range, failing after 100,000 cycles when we applied 46% of the stress needed for instantaneous failure [the ultimate tensile strength (UTS)]. Legs, in contrast, were able to sustain a stress of 76% of the UTS for the same number of cycles to failure. This can be explained by the difference in the composition and structure of the material, two factors that, amongst others, also affect the well-known behaviour of engineering composites. Final failure of the tibiae occurred via one of two different failure modes – crack propagation in tension or buckling in compression – indicating that the tibia is ‘optimized’ by evolution to resist both failure modes equally. These results are further discussed in relation to the evolution and normal use of these two body parts.
Richard J Suderman - One of the best experts on this subject based on the ideXlab platform.
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model reactions for Insect Cuticle sclerotization participation of amino groups in the cross linking of manduca sexta Cuticle protein mscp36
Insect Biochemistry and Molecular Biology, 2010Co-Authors: Richard J Suderman, Karl J Kramer, Neal T Dittmer, Michael R KanostAbstract:Current theories of sclerotization center on protein cross-linking and dehydration as major factors in the hardening and stability of the Insect Cuticle. Several studies have reported the identification of catecholamino acid adducts from sclerotizing Cuticle involving histidine, lysine, and tyrosine, though there have been no reports of a catechol linked between two amino acid residues. Previously, we reported an in vitro model system for sclerotization and observed that stable protein oligomers were formed, presumably through cross-links with oxidized catecholamines [Insect Biochem. Mol. Biol. (2006) 36, 353e365]. Using site-directed mutagenesis we created a mutant lacking histidine, rMsCP36(H65A/H178A), to investigate the possible involvement of the two histidine residues of MsCP36 in cross-linking. Surprisingly, this alteration had little ornoeffecton the formation of proteinoligomers as determined bySDS-PAGEanalysis. Blockingof the freeaminogroupsinlysylsidechainsandtheamino-terminus bysuccinylationdiminished, but did not eliminate, cross-linking of either rMsCP36 or rMsCP36(H65A/H178A). We also examined the possibility that cross-linking was due to intermolecular dityrosine linkages. Immunoblot analysis utilizing a monoclonal antibody known to recognize peptidyl dityrosine indicated that dityrosyl cross-links were present. Taken together, these results indicate that lysyl residues are important for the cross-linking of the Cuticle protein rMsCP36, but that additional residues other than histidine can also contribute. 2010 Elsevier Ltd. All rights reserved.
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ErratumErratum to “Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols”: [Insect Biochemistry and Molecular Biology 36 (2006) 353–365]
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:Erratum to ‘‘Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols’’ [Insect Biochemistry and Molecular Biology 36 (2006) 353–365] Richard J. Suderman, Neal T. Dittmer, Michael R. Kanost , Karl J. Kramer Department of Biochemistry, 103 Willard Hall, Kansas State University, Manhattan, KS 66506-3706, USA Grain Marketing and Production Research Center, Agricultural Research Service, US Department of Agriculture, Manhattan, KS 66506-2736, USA
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erratumerratum to model reactions for Insect Cuticle sclerotization cross linking of recombinant cuticular proteins upon their laccase catalyzed oxidative conjugation with catechols Insect biochemistry and molecular biology 36 2006 353 365
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:Erratum to ‘‘Model reactions for Insect Cuticle sclerotization: Cross-linking of recombinant cuticular proteins upon their laccase-catalyzed oxidative conjugation with catechols’’ [Insect Biochemistry and Molecular Biology 36 (2006) 353–365] Richard J. Suderman, Neal T. Dittmer, Michael R. Kanost , Karl J. Kramer Department of Biochemistry, 103 Willard Hall, Kansas State University, Manhattan, KS 66506-3706, USA Grain Marketing and Production Research Center, Agricultural Research Service, US Department of Agriculture, Manhattan, KS 66506-2736, USA
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model reactions for Insect Cuticle sclerotization cross linking of recombinant cuticular proteins upon their laccase catalyzed oxidative conjugation with catechols
Insect Biochemistry and Molecular Biology, 2006Co-Authors: Richard J Suderman, Michael R Kanost, Neal T Dittmer, Karl J KramerAbstract:The quinone-tanning hypothesis for Insect Cuticle sclerotization proposes that N-acylcatecholamines are oxidized by a phenoloxidase to quinones and quinone methides, which serve as electrophilic cross-linking agents to form covalent cross-links between cuticular proteins. We investigated model reactions for protein cross-linking that occurs during Insect Cuticle sclerotization using recombinant pupal cuticular proteins from the tobacco hornworm, Manduca sexta, fungal or recombinant hornworm laccase-type phenoloxidase, and the cross-linking agent precursor N-acylcatecholamines, N-b-alanydopamine (NBAD) or N-acetyldopamine (NADA). Recombinant M. sexta pupal cuticular proteins MsCP36, MsCP20, and MsCP27 were expressed and purified to near homogeneity. Polyclonal antisera to these recombinant proteins recognized the native proteins in crude pharate brown-colored pupal Cuticle homogenates. Furthermore, antisera to MsCP36, which contains a type-1 Rebers and Riddiford (RR-1) consensus sequence, also recognized an immunoreactive protein in homogenates of larval head capsule exuviae, indicating the presence of an RR-1 cuticular protein in a very hard, sclerotized and nonpigmented Cuticle. All three of the proteins formed small and large oligomers stable to boiling SDS treatment under reducing conditions after reaction with laccase and the N-acylcatecholamines. The optimal reaction conditions for MsCP36 polymerization were 0.3 mM MsCP36, 7.4 mM NBAD and 1.0 U/ml fungal laccase. Approximately 5–10% of the monomer reacted to yield insoluble oligomers and polymers during the reaction, and the monomer also became increasingly insoluble in SDS solution after reaction with the oxidized NBAD. When NADA was used instead of NBAD, less oligomer formation occurred, and most of the protein remained soluble. Radiolabeled NADA became covalently bound to the MsCP36 monomer and oligomers during cross-linking. Recombinant Manduca laccase (MsLac2) also catalyzed the polymerization of MsCP36. These results support the hypothesis that during sclerotization, Insect cuticular proteins are oxidatively conjugated with catechols, a posttranslational process termed catecholation, and then become crosslinked, forming oligomers and subsequently polymers. r 2006 Elsevier Ltd. All rights reserved.