Attachment of zebra and quagga mussel adhesive plaques to diverse substrates

AbstractLike marine mussels, freshwater zebra and quagga mussels adhere via the byssus, a proteinaceous attachment apparatus. Attachment to various surfaces allows these invasive mussels to rapidly spread, however the adhesion mechanism is not fully understood. While marine mussel adhesion mechanics has been studied at the individual byssal-strand level, freshwater mussel adhesion has only been characterized through whole-mussel detachment, without direct interspecies comparisons on different substrates. Here, adhesive strength of individual quagga and zebra mussel byssal plaques were measured on smooth substrates with varying hydrophobicity—glass, PVC, and PDMS. With increased hydrophobicity of substrates, adhesive failures occurred more frequently, and mussel adhesion strength decreased. A new failure mode termed 'footprint failure' was identified, where failure appeared to be adhesive macroscopically, but a microscopic residue remained on the surface. Zebra mussels adhered stronger and more frequently on PDMS than quagga mussels. While their adhesion strengths were similar on PVC, there were differences in the failure mode and the plaque-substrate interface ultrastructure. Comparisons with previous marine mussel studies demonstrated that freshwater mussels adhere with comparable strength despite known differences in protein composition. An improved understanding of freshwater mussel adhesion mechanics may help explain spreading dynamics and will be important in developing effective antifouling surfaces.

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Bioinspired Synthesis of Cross-Linking of Dopamine-Containing Block Copolymers to Form Thermosensitive Covalent Hydrogels

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.531-532.238 ◽

2012 ◽

Vol 531-532 ◽

pp. 238-241 ◽

Cited By ~ 1

Author(s):

Kui Huang ◽

Jin San Chen ◽

Yang Liu

Keyword(s):

Sol Gel ◽

Coupling Efficiency ◽

Pluronic F127 ◽

Cross Linking ◽

Inversion Method ◽

Sustained Drug Delivery ◽

Vis Spectroscopy ◽

Marine Mussels ◽

Mussel Adhesive ◽

Adhesive Proteins

Marine mussels secrete remarkable mussel adhesive proteins (MAPs) for adherence to the substrates upon which they reside. Inspired by the intermolecular cross-linking characteristics of MAPs, we report the synthesis of thermosensitive dopamine modified Pluronic copolymer (PluF127-Dopa) with high coupling efficiency. Under certain temperature and concentration, PluF127-Dopa copolymers in aqueous solution self-assemble into micelles and are able to rapidly form a more stable hydrogels upon addition of oxidizing reagents such as NaIO4, resulting from oxidative cross-linking of dopamine. UV-vis spectroscopy was utilized to identify the reaction intermediates. The sol-gel transition curves of cross-linked PluF127-Dopa hydrogels (CL-PluF127-Dopa) were determined by a vial inversion method. The critical gelation concentration of CL-PluF127-Dopa hydrogels was significantly lower than those for PluF127-Dopa and unmodified Pluronic F127. The apparent mechanical strength of CL-PluF127-Dopa hydrogels was dramatically enhanced compared to those unmodified Pluronic copolymer hydrogels, suitable for sustained drug delivery. These new biomimetic materials are expected to have potential uses in biomedical applications.

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FURTHER STUDIES ON THE CHEMISTRY OF BLOOD SERUM

Journal of Experimental Medicine ◽

10.1084/jem.17.4.444 ◽

1913 ◽

Vol 17 (4) ◽

pp. 444-452 ◽

Cited By ~ 7

Author(s):

Albert A. Epstein

Keyword(s):

Blood Serum ◽

Protein Content ◽

Protein Composition ◽

The Other ◽

Total Protein Content ◽

Protein Nitrogen ◽

Standard Values ◽

The Individual ◽

Chronic Interstitial Nephritis ◽

Functional Deficiency

The following conclusions may be drawn from the results obtained in this study. 1. In the minor surgical cases (considered normal) the chemical composition of the blood serum agrees, as far as its proteins are concerned, with the usual standard values. When examined at different times, the serum of such cases shows no variation in the total protein content or in its individual fractions. The incoagulable nitrogen, however, varies considerably in the total amount in the different cases, as well as in its percentage relations to the other constituents of the serum. 2. The cases of prostatic hypertrophy, with or without chronic interstitial nephritis, show no change from the normal in the character of the protein composition of the serum, nor in the ratio which the individual fractions bear to each other. On the other hand, the incoagulable and non-protein nitrogen of the serum show marked fluctuations, some of which correspond to the degree of functional deficiency of the kidneys. 3. In cases of localized infections of the kidneys, the changes in the blood serum are twofold. One concerns the proteins, and is traceable to the infection; and the other concerns the non-protein nitrogen, results from functional impairment, and varies with the amount of destruction of the kidney substance. Thus an increase in the globulins is observed in these sera similar to that occurring in infections in other localities; the non-protein content increases apparently in direct proportion to the degree of deficiency of the kidney, and becomes diminished when the function of the kidneys improves.

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Biosynthesis and Characterization of the Artificial Protein Consisting of Marine Mussel Adhesive Protein and Silk-Like Protein Sequences

Polymer Journal ◽

10.1295/polymj.pj2006148 ◽

2007 ◽

Vol 39 (4) ◽

pp. 294-295 ◽

Cited By ~ 2

Author(s):

Shinji Hatae ◽

Tetsuo Asakura ◽

Yasumasa Fukushima

Keyword(s):

Protein Sequences ◽

Marine Mussel ◽

Adhesive Protein ◽

Mussel Adhesive Protein ◽

Mussel Adhesive ◽

Artificial Protein

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Underwater Bonding with Charged Polymer Mimics of Marine Mussel Adhesive Proteins

Macromolecules ◽

10.1021/ma201044x ◽

2011 ◽

Vol 44 (13) ◽

pp. 5085-5088 ◽

Cited By ~ 134

Author(s):

James D. White ◽

Jonathan J. Wilker

Keyword(s):

Marine Mussel ◽

Mussel Adhesive Proteins ◽

Charged Polymer ◽

Mussel Adhesive ◽

Adhesive Proteins

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Impact of Immunization Strategies on the Dynamics of Social Contagions

Discrete Dynamics in Nature and Society ◽

10.1155/2020/5284348 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Hao Peng ◽

Wangxin Peng ◽

Dandan Zhao ◽

Zhaolong Hu ◽

Jianmin Han ◽

...

Keyword(s):

Complex Networks ◽

Threshold Model ◽

Network Heterogeneity ◽

Immunization Strategies ◽

Spreading Dynamics ◽

Theoretical Predictions ◽

Underlying Network ◽

Edge Based ◽

The Individual ◽

The Impact

Immunization strategies on complex networks are effective methods to control the spreading dynamics on complex networks, which change the topology and connectivity of the underlying network, thereby affecting the dynamics process of propagation. Here, we use a non-Markovian threshold model to study the impact of immunization strategies on social contagions, in which the immune index greater than (or equal to) 0 corresponds to targeted (random) immunization, and when the immune index is less than 0, the probability of an individual being immunized is inversely related to the degree of the individual. A generalized edge-based compartmental theory is developed to analyze the dynamics of social contagions under immunization, and theoretical predictions are very consistent with simulation results. We find that increasing the immune index or increasing the immune ratio will reduce the final adoption size and increase the outbreak threshold, in other words, make the residual network after immunization not conducive to social contagions. Interestingly, enhancing the network heterogeneity is proved to help improve the immune efficiency of targeted immunization. Besides, the dependence of the outbreak threshold on the network heterogeneity is correlated with the immune ratio and immune index.

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Research on the Application of Weighted Grey Relational Analysis on the Failure Diagnosis of Complicated Electronic Equipment

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.333-335.1543 ◽

2013 ◽

Vol 333-335 ◽

pp. 1543-1547

Author(s):

Hong Yan Zhao ◽

Jun Zhang ◽

Guo Ping Hu ◽

Jian Qiang Zhang

Keyword(s):

Failure Mode ◽

Grey Relational Analysis ◽

Failure Diagnosis ◽

Reference Sequence ◽

Relational Analysis ◽

Grey Relational Grade ◽

Diagnosis Method ◽

Diagnosis Accuracy ◽

The Individual ◽

Grey Relational

Based on weighted grey relational analysis, a new failure diagnosis method for complicated electronic equipments is proposed. First, according to the typical failure samples and weight values to construct grey reference sequence. Secondly, calculating the individual relational coefficient and grade to form grey relational grade sequence. Finally, according to the maximal grey relational grade to choose the corresponding failure mode as the finally diagnosis result. The results of analyses show that the proposed method has higher diagnosis accuracy and reliability than the traditional grey relational method.

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Heat stability of homogenized milk: role of interfacial protein

Journal of Dairy Research ◽

10.1017/s0022029900028430 ◽

1994 ◽

Vol 61 (4) ◽

pp. 507-516 ◽

Cited By ~ 19

Author(s):

Catharina H. McCrae ◽

David Hirst ◽

Andrew J. R. Law ◽

D. Donald Muir

Keyword(s):

Serum Protein ◽

Protein Interactions ◽

Protein Composition ◽

Surface Protein ◽

Heat Stability ◽

Protein Protein Interactions ◽

Ph Profile ◽

Protein Components ◽

The Individual

SummaryThe role of interfacial protein in determining the heat stability of recombined milk was investigated by removing serum protein prior to homogenization and reincorporating it after homogenization. In addition, the surface protein composition of recombined fat globules was probed by analyses of protein load and by quantification of the individual surface protein components using FPLC. In the absence of serum protein, substantially more casein was bound to the fat surface during homogenization. Despite this, the detrimental effect of homogenization on heat stability did not occur when serum protein had been removed from the system. Reincorporation of serum protein after homogenization caused the heat coagulation time–pH profile to revert to a form very similar to that observed without removing serum protein from the system. Thus, adsorption of serum protein did not affect heat stability. It is more likely that heat-induced interactions of serum protein with surface-adsorbed casein promoted heat coagulation. Fat surface area rather than casein load affected these interfacial protein-protein interactions during heating.

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Continued Protein Synthesis at Low [ATP] and [GTP] Enables Cell Adaptation during Energy Limitation

Journal of Bacteriology ◽

10.1128/jb.00852-08 ◽

2008 ◽

Vol 191 (3) ◽

pp. 1083-1091 ◽

Cited By ~ 32

Author(s):

Michael C. Jewett ◽

Mark L. Miller ◽

Yvonne Chen ◽

James R. Swartz

Keyword(s):

Protein Synthesis ◽

Protein Biosynthesis ◽

Protein Composition ◽

System Level ◽

Translation Factors ◽

Metabolic Systems ◽

Energy Limitation ◽

The Individual ◽

Intracellular Energy

ABSTRACT One of biology's critical ironies is the need to adapt to periods of energy limitation by using the energy-intensive process of protein synthesis. Although previous work has identified the individual energy-requiring steps in protein synthesis, we still lack an understanding of the dependence of protein biosynthesis rates on [ATP] and [GTP]. Here, we used an integrated Escherichia coli cell-free platform that mimics the intracellular, energy-limited environment to show that protein synthesis rates are governed by simple Michaelis-Menten dependence on [ATP] and [GTP] (Km ATP, 27 ± 4 μM; Km GTP, 14 ± 2 μM). Although the system-level GTP affinity agrees well with the individual affinities of the GTP-dependent translation factors, the system-level Km ATP is unexpectedly low. Especially under starvation conditions, when energy sources are limited, cells need to replace catalysts that become inactive and to produce new catalysts in order to effectively adapt. Our results show how this crucial survival priority for synthesizing new proteins can be enforced after rapidly growing cells encounter energy limitation. A diminished energy supply can be rationed based on the relative ATP and GTP affinities, and, since these affinities for protein synthesis are high, the cells can adapt with substantial changes in protein composition. Furthermore, our work suggests that characterization of individual enzymes may not always predict the performance of multicomponent systems with complex interdependencies. We anticipate that cell-free studies in which complex metabolic systems are activated will be valuable tools for elucidating the behavior of such systems.

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Bio-Inspired Coloration for Wool Fabrics at Room Temperature

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.671.25 ◽

2015 ◽

Vol 671 ◽

pp. 25-31

Author(s):

Lai Lai So ◽

Liang He ◽

Bin Fei ◽

K.K.L. Cheuk ◽

John H. Xin

Keyword(s):

Room Temperature ◽

Dip Coating ◽

Adhesive Property ◽

Chemical Components ◽

Coating Process ◽

Fastness Properties ◽

Wool Fabrics ◽

Marine Mussels ◽

Novel Method ◽

Mussel Adhesive

Inspired by the remarkable adhesive property of marine mussels, a novel method was developed for wool coloration at room temperature. In this method, dopamine was utilized as a biomimetic precursor for wool coloration due to its structure similar to 3,4-dihydroxyphenylalanine, an important component responsible for mussel adhesive. By using dopamine, wool coloration could be easily achieved at room temperature through a simple dip-coating process. Moreover, the obtained color appearance of wool fabrics could be tuned in a controllable way by the addition of other chemical components to the coloration bath. The dyed wool fabrics showed good color fastness properties.

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