Antifreeze proteins (AFPs) are a subset of ice-binding that control ice crystal growth. They have potential for the cryopreservation cells, tissues, and organs, as well production storage food protection crops from frost. However, detailed mechanism action AFPs is still unclear. Specifically, there controversy regarding reversibility binding to surfaces. The experimentally observed dependence activity on their concentration in solution appears indicate reversible. Here, by series experiments...

Safranine O, a synthetic dye, was found to inhibit growth of ice at millimolar concentrations with an activity comparable that highly evolved antifreeze glycoproteins. inhibits crystals along the crystallographic a-axis, resulting in bipyramidal needles extended <0001> directions as well and plane-specific thermal hysteresis (TH) activity. The interaction safranine is reversible, distinct from previously reported behavior proteins. Spectroscopy molecular dynamics indicate forms aggregates...

Ice-binding proteins that aid the survival of freeze-avoiding, cold-adapted organisms by inhibiting growth endogenous ice crystals are called antifreeze (AFPs). The binding AFPs to causes a separation between melting point and freezing crystal (thermal hysteresis, TH). TH produced hyperactive is an order magnitude higher than typical fish AFP. basis for this difference in activity remains unclear. Here, we have compared time dependence both moderately active using custom-made nanolitre...

Antifreeze proteins (AFPs) and antifreeze glycoproteins (AFGPs) inhibit ice growth via an adsorption-inhibition mechanism that assumes irreversible binding of AF(G)Ps to embryonic crystals the inhibition further growth. The has been questioned remains poorly understood. Here, we used microfluidics fluorescence microscopy investigate nature small large AFGP isoforms. We found both isoforms bind irreversibly ice, as evidenced by microfluidic solution exchange experiments. measured adsorption...

Antifreeze proteins (AFPs) are a widespread class of that bind to ice and facilitate the survival organisms under freezing conditions. AFPs have enormous potential in applications require control over growth. However, nature binding interaction between remains subject debate. Using microfluidics system developed in-house we previously showed hyperactive AFP from Tenebrio molitor beetle, TmAFP, bound an crystal surface after exchanging solution surrounding AFP-free solution. Furthermore,...

Ice-binding proteins (IBPs), including antifreeze proteins, ice structuring thermal hysteresis and recrystallization inhibition are found in cold-adapted organisms protect them from freeze injuries by interacting with crystals. IBPs a variety of organism, fish(1), plants(2, 3), arthropods(4, 5), fungi(6), bacteria(7). adsorb to the surfaces crystals prevent water molecules joining lattice at IBP adsorption location. Ice that grows on crystal surface between adsorbed develops high curvature...

Summary. Late wilt of maize, caused by the fungus Harpophora maydis, is one most important fungal diseases in Egypt. The disease has also been reported from India, Hungary, Spain and Portugal. pathogen survives for long periods soil. currently controlled using maize varieties with reduced sensitivity, but virulent variants may threaten these varieties. Common symptoms have documented over 20 years Upper Galilee (northern Israel), particularly Hula Valley. Recently, prevalence increased. This...

Temperature-controlled microfluidic devices and fluorescence microscopy illustrate the correlation between freezing-point depression distance antifreeze proteins on an ice surface.

By binding to ice, antifreeze proteins (AFPs) depress the freezing point of a solution and inhibit ice recrystallization if does occur. Previous work showed that activity an AFP was incrementally increased by fusing it another protein. Even larger increases in were achieved doubling number ice-binding sites dimerization. Here, we have combined two strategies linking multiple outward-facing AFPs dendrimer significantly increase both size molecule sites. Using heterobifunctional cross-linker,...

In some cold-adapted organisms, over a dozen isoforms of antifreeze (glyco)proteins or AF(G)Ps are present. Although these structurally similar, their ability to inhibit ice growth varies significantly, and, in fish, passive can be much more abundant than the active ones. Laboratory experiments demonstrated decade ago that mixtures AFP exhibit synergistic enhancement each other's activity. The mechanism this synergy effect has remained obscure and is addressed here. Using cold-stages,...

The growth of spontaneously twisted crystals is a common but poorly understood phenomenon. An analysis the formation metastable benzamide polymorph (form II) crystallizing from highly supersaturated aqueous and ethanol solutions given here. Benzamide, first polymorphic molecular crystal reported (1832), would have been helicoidal observed had original authors undertaken an by light microscopy. Polymorphism twisting frequently concur as they are both associated with high thermodynamic driving...

Antifreeze proteins (AFPs) facilitate the survival of diverse organisms in frigid environments by adsorbing to ice crystals and suppressing their growth. The rate AFP accumulation on is determined an interplay between diffusion from bulk solution ice–water interface subsequent adsorption AFPs interface. To interrogate relative importance these two processes, here, we combine nonequilibrium fluorescence experiments with a reaction–diffusion model. We find that as accumulate ice, concentration...

Significance Freezing and melting of ice are one the most common events on Earth. The dynamics crystallization relevant to climate research, mitigating frost damage in agriculture construction, glacier dynamics, tissue food preservation, transportation. We describe use microfluidic devices, accompanied by precise temperature control, examine effect H/D isotope exchange between liquid light water solid heavy growth dynamics. These studies revealed unusual morphologies at surface contact with...

Since some antifreeze proteins and glycoproteins (AF(G)Ps) cannot directly bind to all ice crystal planes, they change morphology by minimizing the area of planes which until growth is halted. Previous studies found that along c-axis (perpendicular basal plane, plane these AF(G)Ps bind) accelerated AF(G)Ps, while other inhibited. The effects this acceleration on thermal hysteresis activity are unknown date. Understanding will elucidate mechanism inhibition AF(G)Ps. Using cold stages an...

According to a USDA report, $161 billion worth of food products was not available for human consumption in 2010 due loss. One potential way reduce loss is prevent damage during the freezing process. This study presents quantitative measurements two primary processes involved freezing: ice nucleation and growth. Using newly developed micro-thermography system, we measured in-situ rates Our findings indicate that growth are distinct opposing processes. Specifically, beef zucchini were...

According to a USDA report, $161 billion worth of food products was not available for human consumption in 2010 due loss. One potential way reduce loss is prevent damage the product during freezing process. This study presents quantitative measurements two primary processes involved foods: ice nucleation and growth. Using newly developed micro-thermography system, we measured in-situ growth rates. We found that rates beef zucchini were significantly higher than those broccoli potato, whereas...

Abstract The growth of spontaneously twisted crystals is a common but poorly understood phenomenon. An analysis the formation metastable benzamide polymorph (form II ) crystallizing from highly supersaturated aqueous and ethanol solutions given here. Benzamide, first polymorphic molecular crystal reported (1832), would have been helicoidal observed had original authors undertaken an by light microscopy. Polymorphism twisting frequently concur as they are both associated with high...

Ice crystal growth and nucleation rate measurements are usually done using light microscopy in liquid transparent samples. Yet, the understanding of important practical problems depends on monitoring ice inside solid materials, for example how rapid leads to structural damage food, or final structure cementitious materials is affected by during curing. Imaging cannot be with visible intrinsically more challenging than imaging. Thermography a technique that uses thermal (infrared) cameras...

Ice-binding proteins (IBPs), including antifreeze proteins, ice structuring thermal hysteresis and recrystallization inhibition are found in cold-adapted organisms protect them from freeze injuries by interacting with crystals. IBPs a variety of organism, fish1, plants2, 3, arthropods4, 5, fungi6, bacteria7. adsorb to the surfaces crystals prevent water molecules joining lattice at IBP adsorption location. Ice that grows on crystal surface between adsorbed develops high curvature lowers...

Abstract Methane clathrates on continental margins contain the largest stores of hydrocarbons Earth, yet role biomolecules in clathrate formation and stability remains almost completely unknown. Here, we report new methane clathrate-binding proteins (CbpAs) bacterial origin discovered metagenomes from gas clathrate-bearing ocean sediments. CbpAs show similar suppression growth as commercial inhibitor polyvinylpyrrolidone inhibit at lower concentrations than antifreeze (AFPs) previously...

The mechanism by which safranine O (SFO), an ice growth inhibitor, halts the of single crystal tetrahydrofuran (THF) clathrate hydrates was explored using microfluidics coupled with cold stages and fluorescence microscopy. THF grown in SFO solutions exhibited morphology changes were shaped as truncated octahedrons or hexagons. Fluorescence microscopy demonstrated that binds to surface on specific planes. Cryo-TEM experiments aqueous containing millimolar concentrations formation bilayered...