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Geologists have debated about what caused the slide debris to travel the distance it did . The " air cushion " theory , an early hypothesis , postulated that a layer of air was trapped between the mass of rock and the mountain , which caused the rock to move a greater distance than would otherwise be expected . " Acou... | 99f013a48000ccc3387ec29b1fc70f84 | 9,505 |
= = Legends = =
| 7bdf74fe002a3791c8b9d85e0cc92d35 | 9,507 |
Numerous legends and misconceptions were spawned in the aftermath of the slide . The entire town of Frank was claimed to have been buried , though much of the town itself was unscathed . The belief that a branch of the Union Bank of Canada had been buried with as much as $ 500 @,@ 000 persisted for many years . The ba... | d1ac17e93169b3c2d5c5ff2b08a19f6b | 9,509 |
Several people , telling amazing stories to those who would listen , passed themselves off as the " sole survivor " in the years following the slide . The most common such tale is that of an infant girl said to have been the only survivor of the slide . Her real name unknown , the girl was called " Frankie Slide " . S... | d384d7c789c11a4c509ad03548e37669 | 9,510 |
= = Legacy = =
| b4fa22c13235a44f06adb277883cbe5d | 9,512 |
Curious sightseers flocked to the site of the slide within the day of the disaster . It has remained a popular tourist destination , in part due to its proximity to the Crowsnest Highway . The province built a roadside turnout in 1941 to accommodate the traffic . Town boosters unsuccessfully sought to have the site de... | 9f7dea12edcc699792e1bb472bdda7bc | 9,514 |
Though Frank recovered from the slide and achieved a peak population of 1 @,@ 000 shortly thereafter , the closure of the mine resulted in a longstanding decline in population . Frank ceased to be an independent community in 1979 when it was amalgamated into the Municipality of Crowsnest Pass along with the neighbouri... | ab34cb88bd9a6ba2ee345b03bdcf3c96 | 9,515 |
= Protein =
| e3e91b4b14c0bcccfbf235d5c137daee | 9,518 |
Proteins ( / ˈproʊˌtiːnz / or / ˈproʊti.ᵻnz / ) are large biomolecules , or macromolecules , consisting of one or more long chains of amino acid residues . Proteins perform a vast array of functions within organisms , including catalysing metabolic reactions , DNA replication , responding to stimuli , and transporting... | d0345f48207b23b3959ed890ba2f2cca | 9,520 |
A linear chain of amino acid residues is called a polypeptide . A protein contains at least one long polypeptide . Short polypeptides , containing less than 20 @-@ 30 residues , are rarely considered to be proteins and are commonly called peptides , or sometimes oligopeptides . The individual amino acid residues are b... | 8959800e29a1463efb80db5932e796d9 | 9,521 |
Once formed , proteins only exist for a certain period of time and are then degraded and recycled by the cell 's machinery through the process of protein turnover . A protein 's lifespan is measured in terms of its half @-@ life and covers a wide range . They can exist for minutes or years with an average lifespan of ... | 71f6836e0e53a68e304d74b1f7d48dcb | 9,522 |
Like other biological macromolecules such as polysaccharides and nucleic acids , proteins are essential parts of organisms and participate in virtually every process within cells . Many proteins are enzymes that catalyse biochemical reactions and are vital to metabolism . Proteins also have structural or mechanical fu... | d65661464f6626aa01672a0d3cfc101f | 9,523 |
Proteins may be purified from other cellular components using a variety of techniques such as ultracentrifugation , precipitation , electrophoresis , and chromatography ; the advent of genetic engineering has made possible a number of methods to facilitate purification . Methods commonly used to study protein structur... | b4257cbc70da85f71d5a2f75cd8d74b4 | 9,524 |
= = Biochemistry = =
| 352b94a2da5c57af2143204211ad6061 | 9,526 |
Most proteins consist of linear polymers built from series of up to 20 different L @-@ α @-@ amino acids . All proteinogenic amino acids possess common structural features , including an α @-@ carbon to which an amino group , a carboxyl group , and a variable side chain are bonded . Only proline differs from this basi... | 9bb960a61265db84b10ff1200f8e7b43 | 9,528 |
The peptide bond has two resonance forms that contribute some double @-@ bond character and inhibit rotation around its axis , so that the alpha carbons are roughly coplanar . The other two dihedral angles in the peptide bond determine the local shape assumed by the protein backbone . The end of the protein with a fre... | 27da0adab8f9144510e0d0d3f70ec54d | 9,529 |
= = = Abundance in cells = = =
| 26f78dbbe54c3419f079f33a95cf3e3d | 9,531 |
It has been estimated that average @-@ sized bacteria contain about 2 million proteins per cell ( e.g. E. coli and Staphylococcus aureus ) . Smaller bacteria , such as Mycoplasma or spirochetes contain fewer molecules , namely on the order of 50 @,@ 000 to 1 million . By contrast , eukaryotic cells are larger and thus... | 51e5b715ac1effbff3e1415e7f9a3d16 | 9,533 |
Importantly , the concentration of individual proteins ranges from a few molecules per cell to hundreds of thousands . In fact , about a third of all proteins is not produced in most cells or only induced under certain circumstances . For instance , of the 20 @,@ 000 or so proteins encoded by the human genome only 6 @... | 15dd08161ce091bedf8589a8ea034d7e | 9,534 |
= = Synthesis = =
| 662a714f6bbd818773e805462fda4611 | 9,536 |
= = = Biosynthesis = = =
| 8353961bb64b79db46923b821e3139ce | 9,539 |
Proteins are assembled from amino acids using information encoded in genes . Each protein has its own unique amino acid sequence that is specified by the nucleotide sequence of the gene encoding this protein . The genetic code is a set of three @-@ nucleotide sets called codons and each three @-@ nucleotide combinatio... | 7a874c1bef37ac48d3860353fdf3611d | 9,541 |
The process of synthesizing a protein from an mRNA template is known as translation . The mRNA is loaded onto the ribosome and is read three nucleotides at a time by matching each codon to its base pairing anticodon located on a transfer RNA molecule , which carries the amino acid corresponding to the codon it recogni... | a819730832b5d1c38f8f690058347239 | 9,542 |
The size of a synthesized protein can be measured by the number of amino acids it contains and by its total molecular mass , which is normally reported in units of daltons ( synonymous with atomic mass units ) , or the derivative unit kilodalton ( kDa ) . Yeast proteins are on average 466 amino acids long and 53 kDa i... | ba047742a7f0d57a7c4d187a5759294f | 9,543 |
= = = Chemical synthesis = = =
| 9d0295ca5f9d7f7b39872694350cdae0 | 9,545 |
Short proteins can also be synthesized chemically by a family of methods known as peptide synthesis , which rely on organic synthesis techniques such as chemical ligation to produce peptides in high yield . Chemical synthesis allows for the introduction of non @-@ natural amino acids into polypeptide chains , such as ... | f920f4bd9661ae10df00f0da4b75d9c1 | 9,547 |
= = Structure = =
| e86941bee721ef15e6abd6a93e41179a | 9,549 |
Most proteins fold into unique 3 @-@ dimensional structures . The shape into which a protein naturally folds is known as its native conformation . Although many proteins can fold unassisted , simply through the chemical properties of their amino acids , others require the aid of molecular chaperones to fold into their... | dadf6ff391965a893d74f1c5d35ae9b5 | 9,551 |
Primary structure : the amino acid sequence . A protein is a polyamide .
| 9caec126949239c1473f0026c3e04dad | 9,552 |
Secondary structure : regularly repeating local structures stabilized by hydrogen bonds . The most common examples are the α @-@ helix , β @-@ sheet and turns . Because secondary structures are local , many regions of different secondary structure can be present in the same protein molecule .
| aa3f9d14ecc80712d4aa7600d9ddc493 | 9,553 |
Tertiary structure : the overall shape of a single protein molecule ; the spatial relationship of the secondary structures to one another . Tertiary structure is generally stabilized by nonlocal interactions , most commonly the formation of a hydrophobic core , but also through salt bridges , hydrogen bonds , disulfid... | e1f8ddb03b04377c6285e3e03ab13ccf | 9,554 |
Quaternary structure : the structure formed by several protein molecules ( polypeptide chains ) , usually called protein subunits in this context , which function as a single protein complex .
| 77174aeebf0290e2d750a471158cec2e | 9,555 |
Proteins are not entirely rigid molecules . In addition to these levels of structure , proteins may shift between several related structures while they perform their functions . In the context of these functional rearrangements , these tertiary or quaternary structures are usually referred to as " conformations " , an... | 2e7181adc03dfc66594ee3025b0a9170 | 9,556 |
Proteins can be informally divided into three main classes , which correlate with typical tertiary structures : globular proteins , fibrous proteins , and membrane proteins . Almost all globular proteins are soluble and many are enzymes . Fibrous proteins are often structural , such as collagen , the major component o... | bdbd36af786d0f4ccda878fedee5c8ce | 9,557 |
A special case of intramolecular hydrogen bonds within proteins , poorly shielded from water attack and hence promoting their own dehydration , are called dehydrons .
| d7f500dc7fa31d642f287067470bf1cd | 9,558 |
= = = Structure determination = = =
| 487b61bd4d80667c1b4e6401eebfa3ba | 9,560 |
Discovering the tertiary structure of a protein , or the quaternary structure of its complexes , can provide important clues about how the protein performs its function . Common experimental methods of structure determination include X @-@ ray crystallography and NMR spectroscopy , both of which can produce informatio... | 49ac67835f6e9e5cf9dd58f3f460bf80 | 9,562 |
Many more gene sequences are known than protein structures . Further , the set of solved structures is biased toward proteins that can be easily subjected to the conditions required in X @-@ ray crystallography , one of the major structure determination methods . In particular , globular proteins are comparatively eas... | 81b25b4d1c0bc5e1ebb15fbe4137c92c | 9,563 |
= = Cellular functions = =
| 019702de6fecbb05cec13b40cb661d46 | 9,565 |
Proteins are the chief actors within the cell , said to be carrying out the duties specified by the information encoded in genes . With the exception of certain types of RNA , most other biological molecules are relatively inert elements upon which proteins act . Proteins make up half the dry weight of an Escherichia ... | 7945d37044ed7b0fb14d791b1467628d | 9,567 |
The chief characteristic of proteins that also allows their diverse set of functions is their ability to bind other molecules specifically and tightly . The region of the protein responsible for binding another molecule is known as the binding site and is often a depression or " pocket " on the molecular surface . Thi... | de37e317ce60ab4fe408351a3f9a0ccb | 9,568 |
Proteins can bind to other proteins as well as to small @-@ molecule substrates . When proteins bind specifically to other copies of the same molecule , they can oligomerize to form fibrils ; this process occurs often in structural proteins that consist of globular monomers that self @-@ associate to form rigid fibers... | 2de9b9a5a01f1d682defb669ae0722bb | 9,569 |
= = = Enzymes = = =
| af974e2cfda386ca74b7041ac0a6a8aa | 9,571 |
The best @-@ known role of proteins in the cell is as enzymes , which catalyse chemical reactions . Enzymes are usually highly specific and accelerate only one or a few chemical reactions . Enzymes carry out most of the reactions involved in metabolism , as well as manipulating DNA in processes such as DNA replication... | 3456892bddfcee7b286dcb678aa18b69 | 9,573 |
The molecules bound and acted upon by enzymes are called substrates . Although enzymes can consist of hundreds of amino acids , it is usually only a small fraction of the residues that come in contact with the substrate , and an even smaller fraction — three to four residues on average — that are directly involved in ... | a97606e4c9811d1a453f7c7793b25abd | 9,574 |
Dirigent proteins are members of a class of proteins that dictate the stereochemistry of a compound synthesized by other enzymes .
| c3345b3acb56f93fa059945ba4d649bd | 9,575 |
= = = Cell signaling and ligand binding = = =
| 0852939aa068be0593e1605100f327b7 | 9,577 |
Many proteins are involved in the process of cell signaling and signal transduction . Some proteins , such as insulin , are extracellular proteins that transmit a signal from the cell in which they were synthesized to other cells in distant tissues . Others are membrane proteins that act as receptors whose main functi... | 8769c7c98c30fd64e198378b6d3844a7 | 9,579 |
Antibodies are protein components of an adaptive immune system whose main function is to bind antigens , or foreign substances in the body , and target them for destruction . Antibodies can be secreted into the extracellular environment or anchored in the membranes of specialized B cells known as plasma cells . Wherea... | cea0b5dd43ed2aeaa1c07d2a688c30b3 | 9,580 |
Many ligand transport proteins bind particular small biomolecules and transport them to other locations in the body of a multicellular organism . These proteins must have a high binding affinity when their ligand is present in high concentrations , but must also release the ligand when it is present at low concentrati... | 3cbafc1f7a382b63bdca7484a0b93ea6 | 9,581 |
Transmembrane proteins can also serve as ligand transport proteins that alter the permeability of the cell membrane to small molecules and ions . The membrane alone has a hydrophobic core through which polar or charged molecules cannot diffuse . Membrane proteins contain internal channels that allow such molecules to ... | 029602ccd4eb422de14e3e2d46c580ce | 9,582 |
= = = Structural proteins = = =
| 8ed419b34625a5c8025cf2ccada330d6 | 9,584 |
Structural proteins confer stiffness and rigidity to otherwise @-@ fluid biological components . Most structural proteins are fibrous proteins ; for example , collagen and elastin are critical components of connective tissue such as cartilage , and keratin is found in hard or filamentous structures such as hair , nail... | f66cc1a48017c50df6f377885395538d | 9,586 |
Other proteins that serve structural functions are motor proteins such as myosin , kinesin , and dynein , which are capable of generating mechanical forces . These proteins are crucial for cellular motility of single celled organisms and the sperm of many multicellular organisms which reproduce sexually . They also ge... | 3680ac07556a84419ba86ca08940e9a2 | 9,587 |
= = Methods of study = =
| b3a8a64af189ebd5e0d9088621fd6d60 | 9,589 |
The activities and structures of proteins may be examined in vitro , in vivo , and in silico . In vitro studies of purified proteins in controlled environments are useful for learning how a protein carries out its function : for example , enzyme kinetics studies explore the chemical mechanism of an enzyme 's catalytic... | b3463c57eb6982d393c0ca878f40a3a2 | 9,591 |
= = = Protein purification = = =
| f85d9583e6377c87bc7f6f724f0b278f | 9,593 |
To perform in vitro analysis , a protein must be purified away from other cellular components . This process usually begins with cell lysis , in which a cell 's membrane is disrupted and its internal contents released into a solution known as a crude lysate . The resulting mixture can be purified using ultracentrifuga... | abd45c36976070a5575f8d7ecbee4ff0 | 9,595 |
For natural proteins , a series of purification steps may be necessary to obtain protein sufficiently pure for laboratory applications . To simplify this process , genetic engineering is often used to add chemical features to proteins that make them easier to purify without affecting their structure or activity . Here... | aaea302f2dc40996822e8c3e0910d227 | 9,596 |
= = = Cellular localization = = =
| f96fa3fd0d0d0f84facdf7412b2f7ffc | 9,598 |
The study of proteins in vivo is often concerned with the synthesis and localization of the protein within the cell . Although many intracellular proteins are synthesized in the cytoplasm and membrane @-@ bound or secreted proteins in the endoplasmic reticulum , the specifics of how proteins are targeted to specific o... | 6d95341e93069b5f18687a8317cacb6e | 9,600 |
Other methods for elucidating the cellular location of proteins requires the use of known compartmental markers for regions such as the ER , the Golgi , lysosomes or vacuoles , mitochondria , chloroplasts , plasma membrane , etc . With the use of fluorescently tagged versions of these markers or of antibodies to known... | ff013a6c4a21419173f8869aa65df0a7 | 9,601 |
Other possibilities exist , as well . For example , immunohistochemistry usually utilizes an antibody to one or more proteins of interest that are conjugated to enzymes yielding either luminescent or chromogenic signals that can be compared between samples , allowing for localization information . Another applicable t... | fd787a9adc539ea31b823c56764644d8 | 9,602 |
Finally , the gold @-@ standard method of cellular localization is immunoelectron microscopy . This technique also uses an antibody to the protein of interest , along with classical electron microscopy techniques . The sample is prepared for normal electron microscopic examination , and then treated with an antibody t... | 95ffecd3727d15352aabfc8919f7b691 | 9,603 |
Through another genetic engineering application known as site @-@ directed mutagenesis , researchers can alter the protein sequence and hence its structure , cellular localization , and susceptibility to regulation . This technique even allows the incorporation of unnatural amino acids into proteins , using modified t... | ab96d89a1b0b8eed6c304e872d4f8950 | 9,604 |
= = = Proteomics = = =
| ce0b7489150a7256f6164001c31c54c4 | 9,606 |
The total complement of proteins present at a time in a cell or cell type is known as its proteome , and the study of such large @-@ scale data sets defines the field of proteomics , named by analogy to the related field of genomics . Key experimental techniques in proteomics include 2D electrophoresis , which allows ... | a8e4042a1c0892833254e579c49c6a55 | 9,608 |
= = = Bioinformatics = = =
| 1de96da1dcb33d843b2dc5a513426dd9 | 9,610 |
A vast array of computational methods have been developed to analyze the structure , function , and evolution of proteins .
| 697f2a6a27beb1e27ab7b552b525788b | 9,612 |
The development of such tools has been driven by the large amount of genomic and proteomic data available for a variety of organisms , including the human genome . It is simply impossible to study all proteins experimentally , hence only a few are subjected to laboratory experiments while computational tools are used ... | 2e8519601efaa021cfa6d55d56d54320 | 9,613 |
= = = = Structure prediction and simulation = = = =
| f133666e49ec6b50e7a6867e5e96c08f | 9,615 |
Complementary to the field of structural genomics , protein structure prediction seeks to develop efficient ways to provide plausible models for proteins whose structures have not yet been determined experimentally . The most successful type of structure prediction , known as homology modeling , relies on the existenc... | 6c4c5893005e9786f60023970313944e | 9,617 |
The processes of protein folding and binding can be simulated using such technique as molecular mechanics , in particular , molecular dynamics and Monte Carlo , which increasingly take advantage of parallel and distributed computing ( Folding @ home project ; molecular modeling on GPU ) . The folding of small α @-@ he... | ff161af9aebec608cf9415775d8ede15 | 9,618 |
= = = = Protein disorder and unstructure prediction = = = =
| d4d8ac484553783b9aef196541251835 | 9,620 |
Many proteins ( in Eucaryota ~ 33 % ) contain large unstructured but biologically functional segments and can be classified as intrinsically disordered proteins . Predicting and analysing protein disorder is , therefore , an important part of protein structure characterisation .
| 7339e0c92d79825a85f704fcb59b3993 | 9,622 |
= = Nutrition = =
| 822dcd27f7ee30ab5735785d06c6ee0a | 9,624 |
Most microorganisms and plants can biosynthesize all 20 standard amino acids , while animals ( including humans ) must obtain some of the amino acids from the diet . The amino acids that an organism cannot synthesize on its own are referred to as essential amino acids . Key enzymes that synthesize certain amino acids ... | 71d3a76ba12c9a5f7b23ffcc0a67d2bd | 9,626 |
In animals , amino acids are obtained through the consumption of foods containing protein . Ingested proteins are then broken down into amino acids through digestion , which typically involves denaturation of the protein through exposure to acid and hydrolysis by enzymes called proteases . Some ingested amino acids ar... | faf88404507c0074ffe00d7d464065dc | 9,627 |
= = History and etymology = =
| 531e9d416c79a5e047931b5359e4b2c3 | 9,629 |
Proteins were recognized as a distinct class of biological molecules in the eighteenth century by Antoine Fourcroy and others , distinguished by the molecules ' ability to coagulate or flocculate under treatments with heat or acid . Noted examples at the time included albumin from egg whites , blood serum albumin , fi... | 730c23a83a5158277a373c3b6418cbb9 | 9,631 |
Proteins were first described by the Dutch chemist Gerardus Johannes Mulder and named by the Swedish chemist Jöns Jacob Berzelius in 1838 . Mulder carried out elemental analysis of common proteins and found that nearly all proteins had the same empirical formula , C400H620N100O120P1S1 . He came to the erroneous conclu... | 79ea3d38e3395de9be3b6620d78792ef | 9,632 |
Early nutritional scientists such as the German Carl von Voit believed that protein was the most important nutrient for maintaining the structure of the body , because it was generally believed that " flesh makes flesh . " Karl Heinrich Ritthausen extended known protein forms with the identification of glutamic acid .... | 805d13849fa9c0eed95be6c3f538441b | 9,633 |
The difficulty in purifying proteins in large quantities made them very difficult for early protein biochemists to study . Hence , early studies focused on proteins that could be purified in large quantities , e.g. , those of blood , egg white , various toxins , and digestive / metabolic enzymes obtained from slaughte... | 4ac134b49df5e9807519be95d309b22d | 9,634 |
Linus Pauling is credited with the successful prediction of regular protein secondary structures based on hydrogen bonding , an idea first put forth by William Astbury in 1933 . Later work by Walter Kauzmann on denaturation , based partly on previous studies by Kaj Linderstrøm @-@ Lang , contributed an understanding o... | f4bc53af31d4d491975439e212332bd5 | 9,635 |
The first protein to be sequenced was insulin , by Frederick Sanger , in 1949 . Sanger correctly determined the amino acid sequence of insulin , thus conclusively demonstrating that proteins consisted of linear polymers of amino acids rather than branched chains , colloids , or cyclols . He won the Nobel Prize for thi... | c13ceb910860aa60434a04dd70df0c11 | 9,636 |
The first protein structures to be solved were hemoglobin and myoglobin , by Max Perutz and Sir John Cowdery Kendrew , respectively , in 1958 . As of 2016 , the Protein Data Bank has over 115 @,@ 000 atomic @-@ resolution structures of proteins . In more recent times , cryo @-@ electron microscopy of large macromolecu... | 28ec98575b668794a7ab1de5391d1c13 | 9,637 |
= = Textbooks = =
| c04017a56a6fb8abba51a001a3714445 | 9,639 |
= = = Databases and projects = = =
| ac31577965d57f14a21a67e88b475ef6 | 9,642 |
The Protein Naming Utility
| dd2851e6b5e22b366e0b61eacde1f042 | 9,644 |
Human Protein Atlas
| a2df91f83576f6256c0b203227888aa5 | 9,645 |
NCBI Entrez Protein database
| 69e9494e44323f6ee359a5b2371089ef | 9,646 |
NCBI Protein Structure database
| 02a725e6d728b9987306282bed34abea | 9,647 |
Human Protein Reference Database
| 2b8ef7b9368bd3633b93451cc0e0bff3 | 9,648 |
Human Proteinpedia
| 649e5624c5103067b189da7534e25ef3 | 9,649 |
Folding @ Home ( Stanford University )
| de8c533e1e837ff09f9f92c5cb348f90 | 9,650 |
Comparative Toxicogenomics Database curates protein – chemical interactions , as well as gene / protein – disease relationships and chemical @-@ disease relationships .
| 132598514a6c63c0cb7dfcfd9d5d8195 | 9,651 |
Bioinformatic Harvester A Meta search engine ( 29 databases ) for gene and protein information .
| 1763779a57dffc65143ef1cdb87db842 | 9,652 |
Protein Databank in Europe ( see also PDBeQuips , short articles and tutorials on interesting PDB structures )
| d0e22309489e0a2b9d7a1620181ccd8f | 9,653 |
Research Collaboratory for Structural Bioinformatics ( see also Molecule of the Month , presenting short accounts on selected proteins from the PDB )
| 7cc9bbe4bf941317336e1402cc44e521 | 9,654 |
Proteopedia – Life in 3D : rotatable , zoomable 3D model with wiki annotations for every known protein molecular structure .
| ecad408ee9bb377c702a1ba548ad5bed | 9,655 |
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