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52-546: See text Notothenioidei is one of 19 suborders of the order Perciformes . The group is found mainly in Antarctic and Subantarctic waters, with some species ranging north to southern Australia and southern South America . Notothenioids constitute approximately 90% of the fish biomass in the continental shelf waters surrounding Antarctica . The Southern Ocean has supported fish habitats for 400 million years; however, modern notothenioids likely appeared sometime after

104-559: A beta helix that form a flat ice-binding surface. Unlike the other AFPs, there is not a singular sequence motif for the ice-binding site. AFP found from the metagenome of the ciliate Euplotes focardii and psychrophilic bacteria has an efficient ice re-crystallization inhibition ability. 1 μM of Euplotes focardii consortium ice-binding protein ( Efc IBP) is enough for the total inhibition of ice re-crystallization in –7.4 °C temperature. This ice-recrystallization inhibition ability helps bacteria to tolerate ice rather than preventing

156-407: A morphology that is largely typical of other coastal perciform fishes. They are not distinguished by a single physical trait, but rather a distinctive set of morphological traits. These include the presence of three flat pectoral fin radials, nostrils located laterally on each side of the head, the lack of a swim bladder , and the presence of multiple lateral lines . Because notothenioids lack

208-515: A compressed beta-solenoid (beta sandwich) with four rows of threonine residus, and this AFP is structurally similar to that modelled for the non-homologous AFP from the pale beauty moth. In contrast, the AFP from the spruce budworm moth is a solenoid that superficially resembles the Tenebrio protein, with a similar ice-binding surface, but it has a triangular cross-section, with longer repeats that lack

260-582: A flat, rigid surface in some AFPs seems to facilitate its interaction with ice via Van der Waals force surface complementarity. Normally, ice crystals grown in solution only exhibit the basal (0001) and prism faces (1010), and appear as round and flat discs. However, it appears the presence of AFPs exposes other faces. It now appears the ice surface 2021 is the preferred binding surface, at least for AFP type I. Through studies on type I AFP, ice and AFP were initially thought to interact through hydrogen bonding (Raymond and DeVries, 1977). However, when parts of

312-597: A molecules influence the enhancing ability of DAFP-1. Optimum activity in TH is correlated with high concentration of enhancer molecules. Li et al. 1998 investigated the effects of pH and solute on thermal hysteresis in Antifreeze proteins from Dendrioides canadensis. TH activity of DAFP-4 was not affected by pH unless the there was a low solute concentration (pH 1) in which TH decreased. The effect of five solutes; succinate, citrate, malate, malonate, and acetate, on TH activity

364-547: A recently shared phylogeny. In Herring and smelt, up to 98% of introns for this gene are shared; the method of transfer is assumed to occur during mating via sperm cells exposed to foreign DNA. The direction of transfer is known to be from herring to smelt as herring have 8 times the copies of AFP gene as smelt (1) and the segments of the gene in smelt house transposable elements which are otherwise characteristic of and common in herring but not found in other fishes. There are two reasons why many types of AFPs are able to carry out

416-404: A swim bladder, the majority of species are benthic or demersal in nature. However, a depth-related diversification has given rise to some species attaining increased buoyancy, using lipid deposits in tissues and reduced ossification of bony structures. This reduced ossification of the skeleton (observed in some notothenioids) changes the weight and creates neutral buoyancy in the water, where

468-464: A thaumatin-like protein and polycarboxylates. Modifications of DAFP-1 with the arginine specific reagent resulted in the partial and complete loss of thermal hysteresis in DAFP-1, indicating that arginine plays a crucial role in enhancing its ability. Different enhancer molecules of DAFP-1 have distinct thermal hysteresis activity. Amornwittawat et al. 2008 found that the number of carboxylate groups in

520-553: Is characterized by depth related diversification. Comparison studies between non-Antarctic and Antarctic species have revealed different ecological processes and genetic differences between the two groups of fish, such as the loss of hemoglobin (in the family Channichthyidae ) and changes in buoyancy. They are distributed mainly throughout the Southern Ocean around the coasts of New Zealand , southern South America , and Antarctica . An estimated 79% of species reside within

572-423: Is likely substantial in most northerly and temperate regions already. Given the known historic consumption of AFPs, it is safe to conclude their functional properties do not impart any toxicologic or allergenic effects in humans. As well, the transgenic process of ice structuring proteins production is widely used in society. Insulin and rennet are produced using this technology. The process does not impact

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624-762: Is often called a "snow flea", produces hyperactive AFPs. Although they are also repetitive and have a flat ice-binding surface, the similarity ends there. Around 50% of the residues are glycine (Gly), with repeats of Gly-Gly- X or Gly-X-X, where X is any amino acid. Each 3-amino-acid repeat forms one turn of a polyproline type II helix. The helices then fold together, to form a bundle that is two helices thick, with an ice-binding face dominated by small hydrophobic residues like alanine, rather than threonine. Other insects, such as an Alaskan beetle, produce hyperactive antifreezes that are even less similar, as they are polymers of sugars ( xylomannan ) rather than polymers of amino acids (proteins). Taken together, this suggests that most of

676-560: Is referred to as convergent evolution . Evidence for convergent evolution in Northern cod ( Gadidae ) and Notothenioids is supported by the findings of different spacer sequences and different organization of  introns and exons as well as unmatching AFGP tripeptide sequences, which emerged from duplications of short ancestral sequences which were differently permuted (for the same tripeptide) by each group. These groups diverged approximately 7-15 million years ago. Shortly after (5-15 mya),

728-486: Is the fossil Mesetaichthys from the Eocene La Meseta Formation of Seymour Island , which already shows close similarities with the extant Dissostichus . These unique environmental conditions in concert with the key evolutionary innovation of Antifreeze glycoprotein promoted widespread radiation within the suborder, leading to the rapid development of new species. Their adaptive radiation

780-685: The Eocene epoch. This period marked the cooling of the Southern Ocean, resulting in the stable, frigid conditions that have persisted to the present day. Another key factor in the evolution of notothenioids is the preponderance of the Antarctic Circumpolar Current (ACC) , a large, slow-moving current that extends to the seafloor and precludes most migration to and from the Antarctic region. The earliest known notothenioid

832-615: The Monte Carlo method ). According to the structure and function study on the antifreeze protein from Pseudopleuronectes americanus , the antifreeze mechanism of the type-I AFP molecule was shown to be due to the binding to an ice nucleation structure in a zipper-like fashion through hydrogen bonding of the hydroxyl groups of its four Thr residues to the oxygens along the [ 01 1 ¯ 2 ] {\displaystyle [01{\overline {1}}2]} direction in ice lattice, subsequently stopping or retarding

884-883: The Scorpaeniformes , are now classified in the Perciformes. The earliest fossil perciform is the extinct serranid Paleoserranus from the Early Paleocene of Mexico , but potential records of "percoids" are known from the Maastrichtian , including Eoserranus , Indiaichthys , and Prolates , although their exact taxonomic identity remains uncertain. The dorsal and anal fins are divided into anterior spiny and posterior soft-rayed portions, which may be partially or completely separated. The pelvic fins usually have one spine and up to five soft rays, positioned unusually far forward under

936-585: The efcIBP gene was inserted to E. coli genome. Efc IBP has a typical AFP structure consisting of multiple beta-sheets and an alpha-helix . Also, all the ice-binding polar residues are at the same site of the protein. The remarkable diversity and distribution of AFPs suggest the different types evolved recently in response to sea level glaciation occurring 1–2 million years ago in the Northern hemisphere and 10-30 million years ago in Antarctica. Data collected from deep sea ocean drilling has revealed that

988-742: The AFGP gene evolved from an ancestral pancreatic trypsinogen gene in Notothenioids. AFGP and trypsinogen genes split via a sequence divergence - an adaptation which occurred alongside the cooling and eventual freezing of the Antarctic Ocean. The evolution of the AFGP gene in Northern cod occurred more recently (~3.2 mya) and emerged from a noncoding sequence via tandem duplications in a Thr-Ala-Ala unit. Antarctic notothenioid fish and arctic cod, Boreogadus saida , are part of two distinct orders and have very similar antifreeze glycoproteins. Although

1040-549: The AFP function may be overcome at extremely cold temperatures, leading to rapid ice growth and death. Freeze tolerant : These species are able to survive body fluid freezing. Some freeze tolerant species are thought to use AFPs as cryoprotectants to prevent the damage of freezing, but not freezing altogether. The exact mechanism is still unknown. However, it is thought AFPs may inhibit recrystallization and stabilize cell membranes to prevent damage by ice. They may work in conjunction with ice nucleating proteins (INPs) to control

1092-523: The AFPs and antifreezes arose after the lineages that gave rise to these various insects diverged. The similarities they do share are the result of convergent evolution. Many microorganisms living in sea ice possess AFPs that belong to a single family. The diatoms Fragilariopsis cylindrus and F. curta play a key role in polar sea ice communities, dominating the assemblages of both platelet layer and within pack ice. AFPs are widespread in these species, and

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1144-524: The Antarctic region. They primarily inhabit seawater temperatures between −2 and 4 °C (28 and 39 °F); however, some of the non-Antarctic species inhabit waters that may be as warm as 10 °C (50 °F) around New Zealand and South America. Seawater temperatures below the freezing point of freshwater (0 °C or 32 °F) are possible due to the greater salinity in the Southern Ocean waters. Notothenioids have an estimated depth range of about 0–1,500 m (0–4,921 ft). Notothenioids display

1196-847: The chemical and physical properties of antifreeze proteins. In 1992, Griffith et al. documented their discovery of AFP in winter rye leaves. Around the same time, Urrutia, Duman and Knight (1992) documented thermal hysteresis protein in angiosperms. The next year, Duman and Olsen noted AFPs had also been discovered in over 23 species of angiosperms , including ones eaten by humans. They reported their presence in fungi and bacteria as well. Recent attempts have been made to relabel antifreeze proteins as ice structuring proteins to more accurately represent their function and to dispose of any assumed negative relation between AFPs and automotive antifreeze, ethylene glycol . These two things are completely separate entities, and show loose similarity only in their function. Numerous fields would be able to benefit from

1248-465: The chin or under the belly. Scales are usually ctenoid (rough to the touch), although sometimes they are cycloid (smooth to the touch) or otherwise modified. Classification of this group is controversial. As traditionally defined before the introduction of cladistics , the Perciformes are almost certainly paraphyletic . Other orders that should possibly be included as suborders are the Scorpaeniformes , Tetraodontiformes , and Pleuronectiformes . Of

1300-438: The closely related Tenebrio and Dendroides beetles are homologous and each 12–13 amino-acid repeat is stabilized by an internal disulfide bond. Isoforms have between 6 and 10 of these repeats that form a coil, or beta-solenoid. One side of the solenoid has a flat ice-binding surface that consists of a double row of threonine residues. Other beetles (genus Rhagium ) have longer repeats without internal disulfide bonds that form

1352-508: The development of the Antarctic Circumpolar Current was formed over 30 million years ago. The cooling of Antarctic imposed from this current caused a mass extinction of teleost species that were unable to withstand freezing temperatures. Notothenioids species with the antifreeze gylcoprotein were able to survive the glaciation event and diversify into new niches. This independent development of similar adaptations

1404-570: The extreme winter months, the spruce budworm resists freezing at temperatures approaching −30 °C. The rate of cooling can influence the thermal hysteresis value of AFPs. Rapid cooling can substantially decrease the nonequilibrium freezing point, and hence the thermal hysteresis value. Consequently, organisms cannot necessarily adapt to their subzero environment if the temperature drops abruptly. Species containing AFPs may be classified as Freeze avoidant : These species are able to prevent their body fluids from freezing altogether. Generally,

1456-421: The fish neither sinks nor floats, and can thus adjust its depth with ease. Notothenioids have a variety of physiological and biochemical adaptations that either permit survival in, or are possible only because of, the generally cold, stable seawater temperatures of the Southern Ocean. These include highly unsaturated membrane lipids and metabolic compensation in enzymatic activity. Many notothenoids have lost

1508-447: The formation of ice. Efc IBP produces also thermal hysteresis gap, but this ability is not as efficient as the ice-recrystallization inhibition ability. Efc IBP helps to protect both purified proteins and whole bacterial cells in freezing temperatures. Green fluorescent protein is functional after several cycles of freezing and melting when incubated with Efc IBP. Escherichia coli survives longer periods in 0 °C temperature when

1560-625: The freezing point of organism's proteins. Bayer-Giraldi et al. 2010 found 30 species from distinct taxa with homologues of ice antifreeze proteins. The diversity is consistent with previous research that has observed the presence of these genes in crustaceans, insects, bacteria, and fungi. Horizontal gene transfer is responsible for the presence of ice antifreeze proteins in two sea diatom species, F. cylindrus and F. curta. AFPs are thought to inhibit ice growth by an adsorption –inhibition mechanism. They adsorb to non basal planes of ice, inhibiting thermodynamically-favored ice growth. The presence of

1612-413: The growth of ice pyramidal planes so as to depress the freeze point. The above mechanism can be used to elucidate the structure-function relationship of other antifreeze proteins with the following two common features: In the 1950s, Norwegian scientist Scholander set out to explain how Arctic fish can survive in water colder than the freezing point of their blood. His experiments led him to believe there

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1664-472: The high oxygen solubility of the Southern Ocean waters. At cold temperatures, the oxygen solubility of water is enhanced. The loss of hemoglobin is partially compensated in these species by the presence of a large, slow-beating heart and enlarged blood vessels that transport a large volume of blood under low pressure to enhance cardiac output. Despite these compensations, the loss of globin proteins still results in reduced physiological performance. Notothenioidei

1716-481: The internal disulfide bonds. The AFP from midges is structurally similar to those from Tenebrio and Dendroides , but the disulfide-braced beta-solenoid is formed from shorter 10 amino-acids repeats, and instead of threonine, the ice-binding surface consists of a single row of tyrosine residues. Springtails (Collembola) are not insects, but like insects, they are arthropods with six legs. A species found in Canada, which

1768-496: The introduction of AFPs into ice cream and yogurt products. This ingredient, labelled ice-structuring protein, has been approved by the Food and Drug Administration . The proteins are isolated from fish and replicated, on a larger scale, in genetically modified yeast. There is concern from organizations opposed to genetically modified organisms (GMOs) who believe that antifreeze proteins may cause inflammation. Intake of AFPs in diet

1820-606: The nearly universal heat shock response (HSR) due to evolution at cold and stable temperatures. Many notothenioid fishes are able to survive in the freezing, ice-laden waters of the Southern Ocean because of the presence of an antifreeze glycoprotein in blood and body fluids. Although many of the Antarctic species have antifreeze proteins in their body fluids, not all of them do. Some non-Antarctic species either produce no or very little antifreeze, and antifreeze concentrations in some species are very low in young, larval fish. They also possess aglomerular kidneys, an adaptation that aids

1872-432: The other AFPs in the following aspects: There are a number of AFPs found in insects, including those from Dendroides , Tenebrio and Rhagium beetles, spruce budworm and pale beauty moths, and midges (same order as flies). Insect AFPs share certain similarities, with most having higher activity (i.e. greater thermal hysteresis value, termed hyperactive) and a repetitive structure with a flat ice-binding surface. Those from

1924-662: The presence of AFP genes as a multigene family indicates the importance of this group for the genus Fragilariopsis . AFPs identified in F. cylindrus belong to an AFP family which is represented in different taxa and can be found in other organisms related to sea ice ( Colwellia spp., Navicula glaciei , Chaetoceros neogracile and Stephos longipes and Leucosporidium antarcticum ) and Antarctic inland ice bacteria ( Flavobacteriaceae ), as well as in cold-tolerant fungi ( Typhula ishikariensis , Lentinula edodes and Flammulina populicola ). Several structures for sea ice AFPs have been solved. This family of proteins fold into

1976-800: The presently recognized suborders, several may be paraphyletic, as well. These are grouped by suborder/superfamily, generally following the text Fishes of the World . Antifreeze protein Unlike the widely used automotive antifreeze, ethylene glycol , AFPs do not lower freezing point in proportion to concentration. Rather, they work in a non colligative manner. This phenomenon allows them to act as an antifreeze at concentrations 1/300th to 1/500th of those of other dissolved solutes. Their low concentration minimizes their effect on osmotic pressure . The unusual properties of AFPs are attributed to their selective affinity for specific crystalline ice forms and

2028-485: The product; it merely makes production more efficient and prevents the death of fish that would otherwise be killed to extract the protein. Currently, Unilever incorporates AFPs into some of its American products, including some Popsicle ice pops and a new line of Breyers Light Double Churned ice cream bars. In ice cream, AFPs allow the production of very creamy, dense, reduced fat ice cream with fewer additives. They control ice crystal growth brought on by thawing on

2080-484: The protection of tissue damage by freezing. Businesses are currently investigating the use of these proteins in: Unilever has obtained UK, US, EU, Mexico, China, Philippines, Australia and New Zealand approval to use a genetically modified yeast to produce antifreeze proteins from fish for use in ice cream production. They are labeled "ISP" or ice structuring protein on the label, instead of AFP or antifreeze protein. One recent, successful business endeavor has been

2132-457: The protein thought to facilitate this hydrogen bonding were mutated, the hypothesized decrease in antifreeze activity was not observed. Recent data suggest hydrophobic interactions could be the main contributor. It is difficult to discern the exact mechanism of binding because of the complex water-ice interface. Currently, attempts to uncover the precise mechanism are being made through use of molecular modelling programs ( molecular dynamics or

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2184-525: The rate of ice propagation following freezing. There are many known nonhomologous types of AFPs. Antifreeze glycoproteins or AFGPs are found in Antarctic notothenioids and northern cod . They are 2.6-3.3 kD. AFGPs evolved separately in notothenioids and northern cod. In notothenioids, the AFGP gene arose from an ancestral trypsinogen-like serine protease gene. The classification of AFPs became more complicated when antifreeze proteins from plants were discovered. Plant AFPs are rather different from

2236-400: The resulting blockade of the ice-nucleation process. AFPs create a difference between the melting point and freezing point (busting temperature of AFP bound ice crystal) known as thermal hysteresis. The addition of AFPs at the interface between solid ice and liquid water inhibits the thermodynamically favored growth of the ice crystal. Ice growth is kinetically inhibited by the AFPs covering

2288-429: The retention of these antifreeze proteins. While the majority of animal species have up to 45% of hemoglobin (or other oxygen-binding and oxygen-transporting pigments) in their blood, the notothenioids of the family Channichthyidae do not express any globin proteins in their blood. As a result, the oxygen-carrying capacity of their blood is reduced to less than 10% that of other fishes. This trait likely arose due to

2340-566: The same function despite their diversity: Antifreeze glycoprotein activity has been observed across several ray-finned species including eelpouts, sculpins, and cod species. Fish species that possess the antifreeze glycoprotein express different levels of protein activity. Polar cod ( Boreogadus saida) exhibit similar protein activity and properties to the Antarctic species, T. borchgrevinki . Both species have higher protein activity than saffron cod ( Eleginus gracilis ). Ice antifreeze proteins have been reported in diatom species to help decrease

2392-519: The two fish orders have similar antifreeze proteins, cod species contain arginine in AFG, while Antarctic notothenioid do not. The role of arginine as an enhancer has been investigated in Dendroides canadensis antifreeze protein (DAFP-1) by observing the effect of a chemical modification using 1-2 cyclohexanedione. Previous research has found various enhancers of this bettles' antifreeze protein including

2444-476: The vicinity of Antarctica. Perciformes See text Perciformes ( / ˈ p ɜːr s ɪ ˌ f ɔːr m iː z / ), also called the Acanthopteri , is an order or superorder of ray-finned fish in the clade Percomorpha . Perciformes means " perch -like". Among the well-known members of this group are perch and darters ( Percidae ), sea bass and groupers ( Serranidae ). Formerly, this group

2496-409: The water-accessible surfaces of ice. Thermal hysteresis is easily measured in the lab with a nanolitre osmometer . Organisms differ in their values of thermal hysteresis. The maximum level of thermal hysteresis shown by fish AFP is approximately −3.5 °C (Sheikh Mahatabuddin et al., SciRep)(29.3 °F). In contrast, aquatic organisms are exposed only to −1 to −2 °C below freezing. During

2548-663: Was first described as a separate grouping, as a "division" he named Nototheniiformes, by the British ichthyologist Charles Tate Regan in 1913., this subsequently has been considered as a suborder of the Percifomes. The name is based on the genus Notothenia , a name coined by Sir John Richardson in 1841 and which means "coming from the south", a reference to the Antarctic distribution of the genus. This classification follows Eastman and Eakin, 2000 and includes references to additional classified species. Most species are restricted to

2600-403: Was reported. Among the five solutes, citrate was shown to have the greatest enhancing effect. This is an example of a proto-ORF model, a rare occurrence where new genes pre exist as a formed open reading frame before the existence of the regulatory element needed to activate them. In fishes, horizontal gene transfer is responsible for the presence of Type II AFP proteins in some groups without

2652-457: Was thought to be even more diverse than it is thought to be now, containing about 41% of all bony fish (about 10,000 species) and about 160 families, which is the most of any order within the vertebrates. However, many of these other families have since been reclassified within their own orders within the clade Percomorpha, significantly reducing the size of the group. In contrast to this splitting, other groups formerly considered distinct, such as

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2704-438: Was “antifreeze” in the blood of Arctic fish. Then in the late 1960s, animal biologist Arthur DeVries was able to isolate the antifreeze protein through his investigation of Antarctic fish. These proteins were later called antifreeze glycoproteins (AFGPs) or antifreeze glycopeptides to distinguish them from newly discovered nonglycoprotein biological antifreeze agents (AFPs). DeVries worked with Robert Feeney (1970) to characterize

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