Journal articles: 'Hyperactive antifreeze proteins'

1

Stein, Benjamin P. "Hyperactive antifreeze proteins." Physics Today 60, no. 5 (2007): 24. http://dx.doi.org/10.1063/1.4796425.

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Graham, Laurie A., Wensheng Qin, Stephen C. Lougheed, Peter L. Davies, and Virginia K. Walker. "Evolution of Hyperactive, Repetitive Antifreeze Proteins in Beetles." Journal of Molecular Evolution 64, no. 4 (2007): 387–98. http://dx.doi.org/10.1007/s00239-005-0256-3.

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Drori, Ran, Yeliz Celik, Peter L. Davies, and Ido Braslavsky. "144 Kinetics of hyperactive and moderate antifreeze proteins." Cryobiology 67, no. 3 (2013): 439. http://dx.doi.org/10.1016/j.cryobiol.2013.09.150.

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Drori, Ran, Yeliz Celik, Peter L. Davies, and Ido Braslavsky. "Ice-binding proteins that accumulate on different ice crystal planes produce distinct thermal hysteresis dynamics." Journal of The Royal Society Interface 11, no. 98 (2014): 20140526. http://dx.doi.org/10.1098/rsif.2014.0526.

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Ice-binding proteins that aid the survival of freeze-avoiding, cold-adapted organisms by inhibiting the growth of endogenous ice crystals are called antifreeze proteins (AFPs). The binding of AFPs to ice causes a separation between the melting point and the freezing point of the ice crystal (thermal hysteresis, TH). TH produced by hyperactive AFPs is an order of magnitude higher than that produced by a typical fish AFP. The basis for this difference in activity remains unclear. Here, we have compared the time dependence of TH activity for both hyperactive and moderately active AFPs using a custom-made nanolitre osmometer and a novel microfluidics system. We found that the TH activities of hyperactive AFPs were time-dependent, and that the TH activity of a moderate AFP was almost insensitive to time. Fluorescence microscopy measurement revealed that despite their higher TH activity, hyperactive AFPs from two insects (moth and beetle) took far longer to accumulate on the ice surface than did a moderately active fish AFP. An ice-binding protein from a bacterium that functions as an ice adhesin rather than as an antifreeze had intermediate TH properties. Nevertheless, the accumulation of this ice adhesion protein and the two hyperactive AFPs on the basal plane of ice is distinct and extensive, but not detectable for moderately active AFPs. Basal ice plane binding is the distinguishing feature of antifreeze hyperactivity, which is not strictly needed in fish that require only approximately 1°C of TH. Here, we found a correlation between the accumulation kinetics of the hyperactive AFP at the basal plane and the time sensitivity of the measured TH.

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Garnham, Christopher P., Jack A. Gilbert, Christopher P. Hartman, Robert L. Campbell, Johanna Laybourn-Parry та Peter L. Davies. "A Ca2+-dependent bacterial antifreeze protein domain has a novel β-helical ice-binding fold". Biochemical Journal 411, № 1 (2008): 171–80. http://dx.doi.org/10.1042/bj20071372.

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AFPs (antifreeze proteins) are produced by many organisms that inhabit ice-laden environments. They facilitate survival at sub-zero temperatures by binding to, and inhibiting, the growth of ice crystals in solution. The Antarctic bacterium Marinomonas primoryensis produces an exceptionally large (>1 MDa) hyperactive Ca2+-dependent AFP. We have cloned, expressed and characterized a 322-amino-acid region of the protein where the antifreeze activity is localized that shows similarity to the RTX (repeats-in-toxin) family of proteins. The recombinant protein requires Ca2+ for structure and activity, and it is capable of depressing the freezing point of a solution in excess of 2 °C at a concentration of 0.5 mg/ml, therefore classifying it as a hyperactive AFP. We have developed a homology-guided model of the antifreeze region based partly on the Ca2+-bound β-roll from alkaline protease. The model has identified both a novel β-helical fold and an ice-binding site. The interior of the β-helix contains a single row of bound Ca2+ ions down one side of the structure and a hydrophobic core down the opposite side. The ice-binding surface consists of parallel repetitive arrays of threonine and aspartic acid/asparagine residues located down the Ca2+-bound side of the structure. The model was tested and validated by site-directed mutagenesis. It explains the Ca2+-dependency of the region, as well its hyperactive antifreeze activity. This is the first bacterial AFP to be structurally characterized and is one of only five hyperactive AFPs identified to date.

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Bar-Dolev, Maya, Yeliz Celik, J. S. Wettlaufer, Peter L. Davies, and Ido Braslavsky. "New insights into ice growth and melting modifications by antifreeze proteins." Journal of The Royal Society Interface 9, no. 77 (2012): 3249–59. http://dx.doi.org/10.1098/rsif.2012.0388.

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Antifreeze proteins (AFPs) evolved in many organisms, allowing them to survive in cold climates by controlling ice crystal growth. The specific interactions of AFPs with ice determine their potential applications in agriculture, food preservation and medicine. AFPs control the shapes of ice crystals in a manner characteristic of the particular AFP type. Moderately active AFPs cause the formation of elongated bipyramidal crystals, often with seemingly defined facets, while hyperactive AFPs produce more varied crystal shapes. These different morphologies are generally considered to be growth shapes. In a series of bright light and fluorescent microscopy observations of ice crystals in solutions containing different AFPs, we show that crystal shaping also occurs during melting. In particular, the characteristic ice shapes observed in solutions of most hyperactive AFPs are formed during melting. We relate these findings to the affinities of the hyperactive AFPs for the basal plane of ice. Our results demonstrate the relation between basal plane affinity and hyperactivity and show a clear difference in the ice-shaping mechanisms of most moderate and hyperactive AFPs. This study provides key aspects associated with the identification of hyperactive AFPs.

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Mochizuki, Kenji, and Masakazu Matsumoto. "Collective Transformation of Water between Hyperactive Antifreeze Proteins: RiAFPs." Crystals 9, no. 4 (2019): 188. http://dx.doi.org/10.3390/cryst9040188.

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We demonstrate, by molecular dynamics simulations, that water confined between a pair of insect hyperactive antifreeze proteins from the longhorn beetle Rhagium inquisitor is discontinuously expelled as the two proteins approach each other at a certain distance. The extensive striped hydrophobic–hydrophilic pattern on the surface, comprising arrays of threonine residues, enables water to form three independent ice channels through the assistance of hydroxyl groups, even at 300 K. The transformation is reminiscent of a freezing–melting transition rather than a drying transition and governs the stable protein–protein separation in the evaluation of the potential of mean force. The collectivity of water penetration or expulsion and the hysteresis in the time scale of ten nanoseconds predict a potential first-order phase transition at the limit of infinite size and provide a new framework for the water-mediated interaction between solutes.

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Kristiansen, Erlend, Casper Wilkens, Bjarne Vincents, et al. "Hyperactive antifreeze proteins from longhorn beetles: Some structural insights." Journal of Insect Physiology 58, no. 11 (2012): 1502–10. http://dx.doi.org/10.1016/j.jinsphys.2012.09.004.

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Meister, K., S. Ebbinghaus, Y. Xu, et al. "Long-range protein-water dynamics in hyperactive insect antifreeze proteins." Proceedings of the National Academy of Sciences 110, no. 5 (2012): 1617–22. http://dx.doi.org/10.1073/pnas.1214911110.

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Mizrahy, Ortal, Maya Bar, and Ido Braslavsky. "115. Enhancing the activity of hyperactive antifreeze proteins with additives." Cryobiology 63, no. 3 (2011): 338. http://dx.doi.org/10.1016/j.cryobiol.2011.09.118.

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Hudait, Arpa, Daniel R. Moberg, Yuqing Qiu, Nathan Odendahl, Francesco Paesani, and Valeria Molinero. "Preordering of water is not needed for ice recognition by hyperactive antifreeze proteins." Proceedings of the National Academy of Sciences 115, no. 33 (2018): 8266–71. http://dx.doi.org/10.1073/pnas.1806996115.

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Antifreeze proteins (AFPs) inhibit ice growth in organisms living in cold environments. Hyperactive insect AFPs are particularly effective, binding ice through “anchored clathrate” motifs. It has been hypothesized that the binding of hyperactive AFPs to ice is facilitated by preordering of water at the ice-binding site (IBS) of the protein in solution. The antifreeze proteinTmAFP displays the best matching of its binding site to ice, making it the optimal candidate to develop ice-like order in solution. Here we use multiresolution simulations to unravel the mechanism by whichTmAFP recognizes and binds ice. We find that water at the IBS of the antifreeze protein in solution does not acquire ice-like or anchored clathrate-like order. Ice recognition occurs by slow diffusion of the protein to achieve the proper orientation with respect to the ice surface, followed by fast collective organization of the hydration water at the IBS to form an anchored clathrate motif that latches the protein to the ice surface. The simulations suggest that anchored clathrate order could develop on the large ice-binding surfaces of aggregates of ice-nucleating proteins (INP). We compute the infrared and Raman spectra of water in the anchored clathrate motif. The signatures of the OH stretch of water in the anchored clathrate motif can be distinguished from those of bulk liquid in the Raman spectra, but not in the infrared spectra. We thus suggest that Raman spectroscopy may be used to probe the anchored clathrate order at the ice-binding surface of INP aggregates.

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Bissoyi, Akalabya, Naama Reicher, Michael Chasnitsky, et al. "Ice Nucleation Properties of Ice-binding Proteins from Snow Fleas." Biomolecules 9, no. 10 (2019): 532. http://dx.doi.org/10.3390/biom9100532.

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Ice-binding proteins (IBPs) are found in many organisms, such as fish and hexapods, plants, and bacteria that need to cope with low temperatures. Ice nucleation and thermal hysteresis are two attributes of IBPs. While ice nucleation is promoted by large proteins, known as ice nucleating proteins, the smaller IBPs, referred to as antifreeze proteins (AFPs), inhibit the growth of ice crystals by up to several degrees below the melting point, resulting in a thermal hysteresis (TH) gap between melting and ice growth. Recently, we showed that the nucleation capacity of two types of IBPs corresponds to their size, in agreement with classical nucleation theory. Here, we expand this finding to additional IBPs that we isolated from snow fleas (the arthropod Collembola), collected in northern Israel. Chemical analyses using circular dichroism and Fourier-transform infrared spectroscopy data suggest that these IBPs have a similar structure to a previously reported snow flea antifreeze protein. Further experiments reveal that the ice-shell purified proteins have hyperactive antifreeze properties, as determined by nanoliter osmometry, and also exhibit low ice-nucleation activity in accordance with their size.

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Pal, Prasun, Sandipan Chakraborty, and Biman Jana. "Deciphering the Role of the Non-ice-binding Surface in the Antifreeze Activity of Hyperactive Antifreeze Proteins." Journal of Physical Chemistry B 124, no. 23 (2020): 4686–96. http://dx.doi.org/10.1021/acs.jpcb.0c01206.

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Patel, Shruti N., and Steffen P. Graether. "Structures and ice-binding faces of the alanine-rich type I antifreeze proteinsThis paper is one of a selection of papers published in this special issue entitled “Canadian Society of Biochemistry, Molecular & Cellular Biology 52nd Annual Meeting — Protein Folding: Principles and Diseases” and has undergone the Journal's usual peer review process." Biochemistry and Cell Biology 88, no. 2 (2010): 223–29. http://dx.doi.org/10.1139/o09-183.

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Antifreeze proteins (AFPs) protect cold-blooded organisms from the damage caused by freezing through their ability to inhibit ice growth. The type I AFP family, found in several fish species, contains proteins that have a high alanine content (>60% of the sequence) and structures that are almost all α-helical. We examine the structure of the type I AFP isoforms HPLC6 from winter flounder, shorthorn sculpin 3, and the winter flounder hyperactive type I AFP. The HPLC6 isoform structure consists of a single α-helix that is 37 residues long, whereas the shorthorn sculpin 3 isoform consists of two helical regions separated by a kink. The high-resolution structure of the hyperactive type I AFP has yet to be determined, but circular dichroism data and analytical ultracentrifugation suggest that the 195 residue protein is a side-by-side dimer of two α-helices. The alanine-rich ice-binding faces of HPLC6 and hyperactive type I AFP are discussed, and we propose that the ice-binding face of the shorthorn sculpin 3 AFP contains Ala14, Ala19, and Ala25. We also propose that the denaturation of hyperactive type I AFP at room temperature is explained by the stabilization of the dimerization interface through hydrogen bonds.

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Braslavsky, Ido, Yeliz Celik, and Peter L. Davies. "Binding Kinetics of Two Hyperactive Antifreeze Proteins are Revealed by Using Novel Microfluidic Devices." Biophysical Journal 96, no. 3 (2009): 547a—548a. http://dx.doi.org/10.1016/j.bpj.2008.12.2965.

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16

Liu, Jun Jie, Yangzong Qin, Maya Bar Dolev, Yeliz Celik, J. S. Wettlaufer, and Ido Braslavsky. "Modelling the influence of antifreeze proteins on three-dimensional ice crystal melt shapes using a geometric approach." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, no. 2147 (2012): 3311–22. http://dx.doi.org/10.1098/rspa.2011.0720.

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The melting of pure axisymmetric ice crystals has been described previously by us within the framework of so-called geometric crystal growth . Non-equilibrium ice crystal shapes evolving in the presence of hyperactive antifreeze proteins (hypAFPs) are experimentally observed to assume ellipsoidal geometries (‘lemon’ or ‘rice’ shapes). To analyse such shapes, we harness the underlying symmetry of hexagonal ice I h and extend two-dimensional geometric models to three-dimensions to reproduce the experimental dissolution process. The geometrical model developed will be useful as a quantitative test of the mechanisms of interaction between hypAFPs and ice.

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Grabowska, Joanna, Anna Kuffel, and Jan Zielkiewicz. "Interfacial water controls the process of adsorption of hyperactive antifreeze proteins onto the ice surface." Journal of Molecular Liquids 306 (May 2020): 112909. http://dx.doi.org/10.1016/j.molliq.2020.112909.

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Liou, Yih-Cherng, Pierre Thibault, Virginia K. Walker, Peter L. Davies, and Laurie A. Graham. "A Complex Family of Highly Heterogeneous and Internally Repetitive Hyperactive Antifreeze Proteins from the BeetleTenebriomolitor†,‡." Biochemistry 38, no. 35 (1999): 11415–24. http://dx.doi.org/10.1021/bi990613s.

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Do, Hackwon, Soon-Jong Kim, Hak Jun Kim, and Jun Hyuck Lee. "Structure-based characterization and antifreeze properties of a hyperactive ice-binding protein from the Antarctic bacteriumFlavobacterium frigorisPS1." Acta Crystallographica Section D Biological Crystallography 70, no. 4 (2014): 1061–73. http://dx.doi.org/10.1107/s1399004714000996.

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Ice-binding proteins (IBPs) inhibit ice growth through direct interaction with ice crystals to permit the survival of polar organisms in extremely cold environments. FfIBP is an ice-binding protein encoded by the Antarctic bacteriumFlavobacterium frigorisPS1. The X-ray crystal structure of FfIBP was determined to 2.1 Å resolution to gain insight into its ice-binding mechanism. The refined structure of FfIBP shows an intramolecular disulfide bond, and analytical ultracentrifugation and analytical size-exclusion chromatography show that it behaves as a monomer in solution. Sequence alignments and structural comparisons of IBPs allowed two groups of IBPs to be defined, depending on sequence differences between the α2 and α4 loop regions and the presence of the disulfide bond. Although FfIBP closely resemblesLeucosporidium(recently re-classified asGlaciozyma) IBP (LeIBP) in its amino-acid sequence, the thermal hysteresis (TH) activity of FfIBP appears to be tenfold higher than that of LeIBP. A comparison of the FfIBP and LeIBP structures reveals that FfIBP has different ice-binding residues as well as a greater surface area in the ice-binding site. Notably, the ice-binding site of FfIBP is composed of a T-A/G-X-T/N motif, which is similar to the ice-binding residues of hyperactive antifreeze proteins. Thus, it is proposed that the difference in TH activity between FfIBP and LeIBP may arise from the amino-acid composition of the ice-binding site, which correlates with differences in affinity and surface complementarity to the ice crystal. In conclusion, this study provides a molecular basis for understanding the antifreeze mechanism of FfIBP and provides new insights into the reasons for the higher TH activity of FfIBP compared with LeIBP.

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Tomalty, Heather E., Laurie A. Graham, Robert Eves, Audrey K. Gruneberg, and Peter L. Davies. "Laboratory-Scale Isolation of Insect Antifreeze Protein for Cryobiology." Biomolecules 9, no. 5 (2019): 180. http://dx.doi.org/10.3390/biom9050180.

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Micromolar concentrations of hyperactive antifreeze proteins (AFPs) from insects can prevent aqueous solutions from freezing down to at least −6 °C. To explore cryopreservation of cells, tissues and organs at these temperatures without ice formation, we have developed a protocol to reliably produce ultrapure Tenebrio molitor AFP from cold-acclimated beetle larvae reared in the laboratory. The AFP was prepared from crude larval homogenates through five cycles of rotary ice-affinity purification, which can be completed in one day. Recovery of the AFP at each step was >90% and no impurities were detected in the final product. The AFP is a mixture of isoforms that are more active in combination than any one single component. Toxicity testing of the purified AFP in cell culture showed no inhibition of cell growth. The production process can easily be scaled up to industrial levels, and the AFP used in cryobiology applications was recovered for reuse in good yield and with full activity.

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Grabowska, Joanna, Anna Kuffel, and Jan Zielkiewicz. "Role of the Solvation Water in Remote Interactions of Hyperactive Antifreeze Proteins with the Surface of Ice." Journal of Physical Chemistry B 123, no. 38 (2019): 8010–18. http://dx.doi.org/10.1021/acs.jpcb.9b05664.

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Davies, P. L., Yih-Cherng Liou, V. K. Walker, and L. A. Graham. "Developmental and environmental regulation of the expression of hyperactive antifreeze proteins in the mealworm beetle, Tenebrio molitor." Biochemistry and Cell Biology 77, no. 4 (1999): 390–91. http://dx.doi.org/10.1139/o99-903ee.

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Chasnitsky, Michael, and Ido Braslavsky. "Ice-binding proteins and the applicability and limitations of the kinetic pinning model." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2146 (2019): 20180391. http://dx.doi.org/10.1098/rsta.2018.0391.

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Ice-binding proteins (IBPs) are unique molecules that bind to and are active on the interface between two phases of water: ice and liquid water. This property allows them to affect ice growth in multiple ways: shaping ice crystals, suppressing the freezing point, inhibiting recrystallization and promoting nucleation. Advances in the protein's production technologies make these proteins promising agents for medical applications among others. Here, we focus on a special class of IBPs that suppress freezing by causing thermal hysteresis (TH): antifreeze proteins (AFPs). The kinetic pinning model describes the dynamics of a growing ice face with proteins binding to it, which eventually slow it down to a halt. We use the kinetic pinning model, with some adjustments made, to study the TH dependence on the solution's concentration of AFPs by fitting the model to published experimental data. We find this model describes the activity of (moderate) type III AFPs well, but is inadequate for the (hyperactive) Tenebrio molitor AFPs. We also find the engulfment resistance to be a key parameter, which depends on the protein's size. Finally, we explain intuitively how TH depends on the seeding time of the ice crystal in the protein solution. Using this insight, we explain the discrepancy in TH measurements between different assays. This article is part of the theme issue ‘The physics and chemistry of ice: scaffolding across scales, from the viability of life to the formation of planets’.

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Banerjee, Rachana, Pratim Chakraborti, Rupa Bhowmick, and Subhasish Mukhopadhyay. "Distinct molecular features facilitating ice-binding mechanisms in hyperactive antifreeze proteins closely related to an Antarctic sea ice bacterium." Journal of Biomolecular Structure and Dynamics 33, no. 7 (2014): 1424–41. http://dx.doi.org/10.1080/07391102.2014.952665.

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Hudait, Arpa, Yuqing Qiu, Nathan Odendahl, and Valeria Molinero. "Hydrogen-Bonding and Hydrophobic Groups Contribute Equally to the Binding of Hyperactive Antifreeze and Ice-Nucleating Proteins to Ice." Journal of the American Chemical Society 141, no. 19 (2019): 7887–98. http://dx.doi.org/10.1021/jacs.9b02248.

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26

Ye, Qilu, Robert Eves, Robert L. Campbell, and Peter L. Davies. "Crystal structure of an insect antifreeze protein reveals ordered waters on the ice-binding surface." Biochemical Journal 477, no. 17 (2020): 3271–86. http://dx.doi.org/10.1042/bcj20200539.

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Antifreeze proteins (AFPs) are characterized by their ability to adsorb to the surface of ice crystals and prevent any further crystal growth. AFPs have independently evolved for this purpose in a variety of organisms that encounter the threat of freezing, including many species of polar fish, insects, plants and microorganisms. Despite their diverse origins and structures, it has been suggested that all AFPs can organize ice-like water patterns on one side of the protein (the ice-binding site) that helps bind the AFP to ice. Here, to test this hypothesis, we have solved the crystal structure at 2.05 Å resolution of an AFP from the longhorn beetle, Rhagium mordax with five molecules in the unit cell. This AFP is hyperactive, and its crystal structure resembles that of the R. inquisitor ortholog in having a β-solenoid fold with a wide, flat ice-binding surface formed by four parallel rows of mainly Thr residues. The key difference between these structures is that the R. inquisitor AFP crystallized with its ice-binding site (IBS) making protein–protein contacts that limited the surface water patterns. Whereas the R. mordax AFP crystallized with the IBSs exposed to solvent enabling two layers of unrestricted ordered surface waters to be seen. These crystal waters make close matches to ice lattice waters on the basal and primary prism planes.

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Kong, Charles H. Z., Ivanhoe K. H. Leung, and Vijayalekshmi Sarojini. "Synthetic insect antifreeze peptides modify ice crystal growth habit." CrystEngComm 19, no. 16 (2017): 2163–67. http://dx.doi.org/10.1039/c7ce00232g.

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Cheng, Jing, Yuichi Hanada, Ai Miura, Sakae Tsuda, and Hidemasa Kondo. "Hydrophobic ice-binding sites confer hyperactivity of an antifreeze protein from a snow mold fungus." Biochemical Journal 473, no. 21 (2016): 4011–26. http://dx.doi.org/10.1042/bcj20160543.

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Snow mold fungus, Typhula ishikariensis, secretes seven antifreeze protein isoforms (denoted TisAFPs) that assist in the survival of the mold under snow cover. Here, the X-ray crystal structure of a hyperactive isoform, TisAFP8, at 1.0 Å resolution is presented. TisAFP8 folds into a right-handed β-helix accompanied with a long α-helix insertion. TisAFP8 exhibited significantly high antifreeze activity that is comparable with other hyperactive AFPs, despite its close structural and sequence similarity with the moderately active isoform TisAFP6. A series of mutations introduced into the putative ice-binding sites (IBSs) in the β-sheet and adjacent loop region reduced antifreeze activity. A double-mutant A20T/A212S, which comprises a hydrophobic patch between the β-sheet and loop region, caused the greatest depression of antifreeze activity of 75%, when compared with that of the wild-type protein. This shows that the loop region is involved in ice binding and hydrophobic residues play crucial functional roles. Additionally, bound waters around the β-sheet and loop region IBSs were organized into an ice-like network and can be divided into two groups that appear to mediate separately TisAFP and ice. The docking model of TisAFP8 with the basal plane via its loop region IBS reveals a better shape complementarity than that of TisAFP6. In conclusion, we present new insights into the ice-binding mechanism of TisAFP8 by showing that a higher hydrophobicity and better shape complementarity of its IBSs, especially the loop region, may render TisAFP8 hyperactive to ice binding.

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Arai, Tatsuya, Akari Yamauchi, Ai Miura, et al. "Discovery of Hyperactive Antifreeze Protein from Phylogenetically Distant Beetles Questions Its Evolutionary Origin." International Journal of Molecular Sciences 22, no. 7 (2021): 3637. http://dx.doi.org/10.3390/ijms22073637.

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Beetle hyperactive antifreeze protein (AFP) has a unique ability to maintain a supercooling state of its body fluids, however, less is known about its origination. Here, we found that a popular stag beetle Dorcus hopei binodulosus (Dhb) synthesizes at least 6 isoforms of hyperactive AFP (DhbAFP). Cold-acclimated Dhb larvae tolerated −5 °C chilled storage for 24 h and fully recovered after warming, suggesting that DhbAFP facilitates overwintering of this beetle. A DhbAFP isoform (~10 kDa) appeared to consist of 6−8 tandem repeats of a 12-residue consensus sequence (TCTxSxNCxxAx), which exhibited 3 °C of high freezing point depression and the ability of binding to an entire surface of a single ice crystal. Significantly, these properties as well as DNA sequences including the untranslated region, signal peptide region, and an AFP-encoding region of Dhb are highly similar to those identified for a known hyperactive AFP (TmAFP) from the beetle Tenebrio molitor (Tm). Progenitor of Dhb and Tm was branched off approximately 300 million years ago, so no known evolution mechanism hardly explains the retainment of the DNA sequence for such a long divergence period. Existence of unrevealed gene transfer mechanism will be hypothesized between these two phylogenetically distant beetles to acquire this type of hyperactive AFP.

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Daraboina, Nagu, Christine Malmos Perfeldt, and Nicolas von Solms. "Testing antifreeze protein from the longhorn beetle Rhagium mordax as a kinetic gas hydrate inhibitor using a high-pressure micro differential scanning calorimeter." Canadian Journal of Chemistry 93, no. 9 (2015): 1025–30. http://dx.doi.org/10.1139/cjc-2014-0543.

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Low dosage kinetic hydrate inhibitors are employed as alternatives to expensive thermodynamic inhibitors to manage the risk of hydrate formation inside oil and gas pipelines. These chemicals need to be tested at appropriate conditions in the laboratory before deployment in the field. A high pressure micro differential scanning calorimeter HP-μDSC VII (Setaram Inc.) containing two 50 cc high pressure cells (maximum operating pressure 40 MPa; temperature range –40 to 120 °C) was employed to observe methane hydrate formation and decomposition in the presence of hyperactive antifreeze protein from Rhagium mordax (RmAFP) and biodegradable synthetic kinetic inhibitor Luvicap Bio. A systematic capillary dispersion method was used, and this method enhanced the ability to detect the effect of various inhibitors on hydrate formation with small quantities. The presence of RmAFP and Luvicap Bio influence (inhibit) the hydrate formation phenomena significantly. Luvicap Bio (relative strength compared to buffer: 13.3 °C) is stronger than RmAFP (9.8 °C) as a nucleation inhibitor. However, the presence RmAFP not only delays hydrate nucleation but also reduces the amount of hydrate formed (20%–30%) after nucleation significantly. Unlike RmAFP, Luvicap Bio promoted the amount of hydrate formed after nucleation. The superior hydrate growth inhibition capability and predictable hydrate melting behavior compared to complex, heterogeneous hydrate melting with Luvicap Bio shows that RmAFP can be a potential natural green kinetic inhibitor for hydrate formation in pipelines.

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Pal, Prasun, Sandipan Chakraborty, and Biman Jana. "Differential Hydration of Ice‐Binding Surface of Globular and Hyperactive Antifreeze Proteins." Advanced Theory and Simulations, July 8, 2021, 2100090. http://dx.doi.org/10.1002/adts.202100090.

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32

Khan, N. M. Mofiz Uddin, Tatsuya Arai, Sakae Tsuda, and Hidemasa Kondo. "Characterization of microbial antifreeze protein with intermediate activity suggests that a bound-water network is essential for hyperactivity." Scientific Reports 11, no. 1 (2021). http://dx.doi.org/10.1038/s41598-021-85559-x.

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AbstractAntifreeze proteins (AFPs) inhibit ice growth by adsorbing onto specific ice planes. Microbial AFPs show diverse antifreeze activity and ice plane specificity, while sharing a common molecular scaffold. To probe the molecular mechanisms responsible for AFP activity, we here characterized the antifreeze activity and crystal structure of TisAFP7 from the snow mold fungus Typhula ishikariensis. TisAFP7 exhibited intermediate activity, with the ability to bind the basal plane, compared with a hyperactive isoform TisAFP8 and a moderately active isoform TisAFP6. Analysis of the TisAFP7 crystal structure revealed a bound-water network arranged in a zigzag pattern on the surface of the protein’s ice-binding site (IBS). While the three AFP isoforms shared the water network pattern, the network on TisAFP7 IBS was not extensive, which was likely related to its intermediate activity. Analysis of the TisAFP7 crystal structure also revealed the presence of additional water molecules that form a ring-like network surrounding the hydrophobic side chain of a crucial IBS phenylalanine, which might be responsible for the increased adsorption of AFP molecule onto the basal plane. Based on these observations, we propose that the extended water network and hydrophobic hydration at IBS together determine the TisAFP activity.

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Journal articles on the topic 'Hyperactive antifreeze proteins'

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