scholarly journals Snap-jaw morphology is specialized for high-speed power amplification in the Dracula ant, Mystrium camillae

2018 ◽  
Vol 5 (12) ◽  
pp. 181447 ◽  
Author(s):  
Fredrick J. Larabee ◽  
Adrian A. Smith ◽  
Andrew V. Suarez
Keyword(s):  
High Speed ◽  
Muscle Power ◽  
Element Analysis ◽  
Predator Prey ◽  
Mantis Shrimp ◽  
Power Amplification ◽  
Form Function ◽  
Function Relationship ◽  
Relationship Of ◽  
Insight Into

What is the limit of animal speed and what mechanisms produce the fastest movements? More than natural history trivia, the answer provides key insight into the form–function relationship of musculoskeletal movement and can determine the outcome of predator–prey interactions. The fastest known animal movements belong to arthropods, including trap-jaw ants, mantis shrimp and froghoppers, that have incorporated latches and springs into their appendage systems to overcome the limits of muscle power. In contrast to these examples of power amplification, where separate structures act as latch and spring to accelerate an appendage, some animals use a ‘snap-jaw’ mechanism that incorporates the latch and spring on the accelerating appendage itself. We examined the kinematics and functional morphology of the Dracula ant, Mystrium camillae , who use a snap-jaw mechanism to quickly slide their mandibles across each other similar to a finger snap. Kinematic analysis of high-speed video revealed that snap-jaw ant mandibles complete their strike in as little as 23 µsec and reach peak velocities of 90 m s −1 , making them the fastest known animal appendage. Finite-element analysis demonstrated that snap-jaw mandibles were less stiff than biting non-power-amplified mandibles, consistent with their use as a flexible spring. These results extend our understanding of animal speed and demonstrate how small changes in morphology can result in dramatic differences in performance.

scholarly journals Achieving High-Speed Retraction in a Stretchable Hydrogel

2020 ◽  
Author(s):  
Rosa Maria Badani Prado ◽  
Satish Mishra ◽  
Buckston Morgan ◽  
Rangana Wijayapala ◽  
Seyed Meysam Hashemnejad ◽  
...  
Keyword(s):  
High Speed ◽  
Biological Tissues ◽  
Biological Species ◽  
Vital Role ◽  
Polypropylene Glycol ◽  
Glycol Diacrylate ◽  
Mantis Shrimp ◽  
Power Amplification ◽  
Short Period ◽  
Very High

Many biological species apply the power amplification mechanism for locomotion, feeding, and protection. In power amplification, a biological system rapidly releases stored-energy by achieving a very high velocity over a short period of time, resulting in high power output. Such power amplification allows insects such as locust to jump and Mantis shrimp to kill prey by its appendage strike. Biological elastomeric polymers such as resilin play a vital role in the power amplification process because of their high stretchability and resilience. In synthetic materials, although<br>crosslinked rubbers display high stretchability and resilience, such is difficult to achieve in the water-containing systems such as in hydrogels, commonly considered materials for mimicking biological tissues. Here, we have used a simple free-radical polymerization of acrylic acid (AAc), methacrylamide (MAAm), and polypropylene glycol diacrylate (PPGDA) to obtain hydrogels. In these gels, the polymerized AAc and MAAm act as hydrophilic blocks and PPG as hydrophobic, and the gel structure resemble that of resilin consisting of hydrophilic and hydrophobic components. The bioinspired gels display very high stretchability, as high as eight times the original length, and greater than 90% resilience. In addition, the gel samples can reach a retraction velocity of 16 m/s with an acceleration of 4X10^3 m/s2. These values are similar or better than those observed in water containing biological systems, such as appendage strikes in Mantis shrimp, etc. To the best of our knowledge, such performance has not been reported in the<br>literature for any water containing networks.

scholarly journals The Role of the Fibronectin IGD Motif in Stimulating Fibroblast Migration

2007 ◽  
Vol 282 (49) ◽  
pp. 35530-35535 ◽  
Author(s):  
Christopher J. Millard ◽  
Ian R. Ellis ◽  
Andrew R. Pickford ◽  
Ana M. Schor ◽  
Seth L. Schor ◽  
...  
Keyword(s):  
Fibroblast Migration ◽  
Wide Range ◽  
Migration Stimulating Factor ◽  
Function Relationship ◽  
Relationship Of ◽  
Stimulating Factor ◽  
Insight Into ◽  
Stimulation Of

The motogenic activity of migration-stimulating factor, a truncated isoform of fibronectin (FN), has been attributed to the IGD motifs present in its FN type 1 modules. The structure-function relationship of various recombinant IGD-containing FN fragments is now investigated. Their structure is assessed by solution state NMR and their motogenic ability tested on fibroblasts. Even conservative mutations in the IGD motif are inactive or have severely reduced potency, while the structure remains essentially the same. A fragment with two IGD motifs is 100 times more active than a fragment with one and up to 106 times more than synthetic tetrapeptides. The wide range of potency in different contexts is discussed in terms of cryptic FN sites and cooperativity. These results give new insight into the stimulation of fibroblast migration by IGD motifs in FN.

scholarly journals Mechanics of snake biting: Experiments and modelling

2019 ◽  
Author(s):  
Lakshminath Kundanati ◽  
Roberto Guarino ◽  
Michele Menegon ◽  
Nicola M. Pugno
Keyword(s):  
Mechanical Properties ◽  
Mechanical Loads ◽  
Tissue Interactions ◽  
Form Function ◽  
Tissue Phantoms ◽  
The Difference ◽  
Function Relationship ◽  
Experimental Values ◽  
Relationship Of ◽  
Shape And Size

AbstractAmong all the vertebrates, snakes possess the most sophisticated venom delivering system using their fangs. Fangs of many animals are well adapted to the mechanical loads experienced during the functions such as breaking the diet and puncturing the skin of the prey. Thus, investigation and modelling of puncturing mechanics of snakes is of importance to understand the form-function relationship of the fangs and tissue-fang interactions in detail. We have thus chosen fangs of two snake species i.e. viper (Bitis arietans) and burrowing snake (Atractaspis aterrima), with different shape and size and performed insertion experiments using tissue phantoms. Our results showed that both the species have similar mechanical properties but there was a difference in the insertion forces owing to the difference in shape of the fang. Also, our modelling of the fang-tissue interactions predicted some parameters close to the experimental values. Thus, our study can help in the development of bioinspired needles that can potentially have reduced insertion forces and less damage to the tissue.

scholarly journals Achieving High-Speed Retraction in a Stretchable Hydrogel

2020 ◽  
Author(s):  
Rosa Maria Badani Prado ◽  
Satish Mishra ◽  
Buckston Morgan ◽  
Rangana Wijayapala ◽  
Seyed Meysam Hashemnejad ◽  
...  
Keyword(s):  
High Speed ◽  
Biological Tissues ◽  
Biological Species ◽  
Vital Role ◽  
Polypropylene Glycol ◽  
Glycol Diacrylate ◽  
Mantis Shrimp ◽  
Power Amplification ◽  
Short Period ◽  
Very High

Many biological species apply the power amplification mechanism for locomotion, feeding, and protection. In power amplification, a biological system rapidly releases stored-energy by achieving a very high velocity over a short period of time, resulting in high power output. Such power amplification allows insects such as locust to jump and Mantis shrimp to kill prey by its appendage strike. Biological elastomeric polymers such as resilin play a vital role in the power amplification process because of their high stretchability and resilience. In synthetic materials, although<br>crosslinked rubbers display high stretchability and resilience, such is difficult to achieve in the water-containing systems such as in hydrogels, commonly considered materials for mimicking biological tissues. Here, we have used a simple free-radical polymerization of acrylic acid (AAc), methacrylamide (MAAm), and polypropylene glycol diacrylate (PPGDA) to obtain hydrogels. In these gels, the polymerized AAc and MAAm act as hydrophilic blocks and PPG as hydrophobic, and the gel structure resemble that of resilin consisting of hydrophilic and hydrophobic components. The bioinspired gels display very high stretchability, as high as eight times the original length, and greater than 90% resilience. In addition, the gel samples can reach a retraction velocity of 16 m/s with an acceleration of 4X10^3 m/s2. These values are similar or better than those observed in water containing biological systems, such as appendage strikes in Mantis shrimp, etc. To the best of our knowledge, such performance has not been reported in the<br>literature for any water containing networks.

scholarly journals CYP154C5 Regioselectivity in Steroid Hydroxylation Explored by Substrate and Protein Engineering

2020 ◽  
Author(s):  
Paula Bracco ◽  
Hein J. Wijma ◽  
Bastian Nicolai ◽  
Jhon Alexander Rodriguez Buitrago ◽  
Thomas Klünemann ◽  
...  
Keyword(s):  
Active Site ◽  
Md Simulation ◽  
Binding Mode ◽  
Valuable Insight ◽  
P450 Monooxygenase ◽  
Steroid Hydroxylation ◽  
Substrate Engineering ◽  
Function Relationship ◽  
Relationship Of ◽  
Insight Into

AbstractCYP154C5 from Nocardia farcinica is a P450 monooxygenase able to hydroxylate a range of steroids with high regio- and stereoselectivity at the 16α-position. Using protein and substrate engineering based on the crystal structure of CYP154C5, an altered regioselectivity of the enzyme in steroid hydroxylation could be achieved. Thus, conversion of progesterone by mutant CYP154C5 F92A resulted in formation of the corresponding 21-hydroxylated product 11-deoxycorticosterone in addition to 16α-hydroxylation. Using MD simulation, this altered regioselectivity appeared to result from an alternate binding mode of the steroid in the active site of mutant F92A. MD simulation further suggested that water entrance to the active site caused higher uncoupling in this mutant. Moreover, exclusive 15α-hydroxylation was observed for wild-type CYP154C5 in the conversion of 5α-androstan-3-one, lacking an oxy-functional group at C17. Overall, our data give valuable insight into the structure-function relationship of this cytochrome P450 monooxygenase for steroid hydroxylation.

Investigating targets for neuropharmacological intervention by molecular dynamics simulations

2019 ◽  
Vol 47 (3) ◽  
pp. 909-918
Author(s):  
Giulia Rossetti ◽  
Achim Kless ◽  
Luhua Lai ◽  
Tiago F. Outeiro ◽  
Paolo Carloni
Keyword(s):  
Molecular Dynamics ◽  
Disease Onset ◽  
Physiological Saline ◽  
Diagnostic Tools ◽  
Biologically Relevant ◽  
Neuroactive Drugs ◽  
Function Relationship ◽  
Dynamics Simulations ◽  
Relationship Of ◽  
Insight Into

Abstract Medical research has identified over 500 brain disorders. Among these, there are still only very few neuropathologies whose causes are fully understood and, consequently, very few drugs whose mechanism of action is known. No FDA drug has been identified for major neurodegenerative diseases, such as Alzheimer's and Parkinson's. We still lack effective treatments and strategies for modulating progression or even early neurodegenerative disease onset diagnostic tools. A great support toward the highly needed identification of neuroactive drugs comes from computer simulation methods and, in particular, from molecular dynamics (MD). This provides insight into structure–function relationship of a target and predicts structure, dynamics and energetics of ligand/target complexes under biologically relevant conditions like temperature and physiological saline concentration. Here, we present examples of the predictive power of MD for neuroactive ligands/target complexes. This brief survey from our own research shows the usefulness of partnerships between academia and industry, and from joint efforts between experimental and theoretical groups.

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