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protein
Longman Dictionary of Contemporary English
protein
noun
COLLOCATIONS FROM OTHER ENTRIES
fat/protein/alcohol etc content
▪ the fat content of cheese
▪ water with a low salt content
protein/carbohydrate/alcohol etc metabolism
▪ The vast majority of alcohol metabolism occurs in the liver.
textured vegetable protein
COLLOCATIONS FROM CORPUS
■ ADJECTIVE
binding
▪ Minimally, the binding of protein to this element should alter the chromatin structure of the promoter.
▪ One of these binding proteins, IGFBP-1, is of particular interest because of its known relationship to metabolism.
▪ Hepatocytes also express non-integrin, matrix binding proteins.
▪ The octamer site binds both the constitutively expressed transcription factor Oct-1 and a novel cervical octamer binding protein.
different
▪ But they probably result from the nature of the dimerization interfaces, which are very different for each protein.
▪ A problem with this technique lies with the variance seen in the number of tyrosine residues in the different proteins.
▪ This depends on a huge number of different receptor proteins, each tuned to a different sort of chemical stimulus.
▪ This burgeoning family now contains over 20 different proteins, principally identified through sequence homology.
▪ In the first experiment, dietary nitrogen was given in casein at four different protein values ranging from 5 to 16%.
▪ Sometimes, different protein molecules will fit together, like the pieces of a three-dimensional jigsaw, to form larger-scale structures.
high
▪ Sefa-Dedeh is now developing a simple process to prepare a high protein food from cereals and legumes.
▪ The plant protein isolates are highest in protein content.
▪ Made by time-honoured methods, Edam is high in protein, vitamins and minerals.
▪ And mounting evidence shows diets high in animal protein trigger calcium loss from bones, increasing osteoporosis risks.
▪ Nuts are high in protein and essential fats, and add taste and texture to all sorts of dishes.
▪ Although they are an inexpensive source of the highest quality protein, they are high in cholesterol.
▪ Tasty eating made from only natural ingredients, low in calories and high in protein.
▪ When men crave, they usually want foods which combine high protein with high fat, such as steak and chips.
human
▪ No significant homology could be detected between the human and marsupial proteins outside this motif.
▪ Comparison of deduced amino acid sequences of the mouse and human TEF-1 proteins.
▪ The predicted human protein contains only one amino acid change at position 101, from Asn in rat to Ser in human.
▪ The nucleotide and deduced amino acid sequence of the human ribosomal protein L12 cDNA.
nuclear
▪ Oligonucleotides were radioactively labelled, complexed with F9 nuclear proteins and separated by agarose gel electrophoresis.
▪ Labelled oligonucleotides were incubated with F9 nuclear proteins in the presence or absence of cold competitors.
▪ Radiation induces nuclear regulating proteins, these are able to regulate cytokines, which may themselves have secondary effects on eicosanoids.
other
▪ In addition, protein structure, post-translational modification, or interaction with other proteins may affect site recognition.
▪ Be prepared for some children to be vegetarian, so make sure there are other forms of protein than meat.
▪ This idea is supported by the potential similarity of two other DNA-binding proteins that regulate transcription during the yeast cell cycle.
▪ This is similar to the commonly observed phosphate-binding sites at helix termini in other proteins and, in particular, other repressor-operator complexes.
▪ Prices also rose relatively less than those of other proteins, such as fish, cheese and eggs.
▪ It was like no other protein that anyone had described before, and so there was no clue to its function.
total
▪ The concentrations of total lipid and protein in gall bladder bile were not significantly different between the two groups.
▪ Due to the presence of this monoclonal protein, the serum total protein will be elevated.
▪ The total protein concentration did not differ between the two groups as shown by Yamazaki etal.
▪ The nucleation time did not correlate with either total lipid concentration or total protein concentration.
▪ The total protein content of the tube was evaluated by the Bradford protein method.
▪ Furthermore, a high biliary concentration of total protein is reported to reduce bile metastability.
viral
▪ Addition of this phosphate group impairs the function of the essential protein, and viral protein synthesis fails to begin.
▪ One of the three drugs they received was ritonavir, an inhibitor of the enzyme protease, which processes key viral proteins.
▪ But exactly how viral protein synthesis is selectively inhibited, leaving cellular protein synthesis relatively unaffected, is still not clear.
▪ During these final stages host enzymes attach carbohydrate groups to certain viral proteins, converting them into glycoproteins.
whole
▪ These studies of whole body protein metabolism, however, simply reflect an average of events occurring in all individual tissues.
▪ Peptides, less antigenic substrates than whole protein, are effective in inducing remission in Crohn's disease.
▪ Powell-Tuck etal measured whole body protein metabolism in 19 patients with ulcerative colitis, while they were receiving enteral or intravenous nutrition.
▪ The contribution, therefore, of the pathological colon to this increased whole body protein synthesis and breakdown was unknown.
▪ Moreover, there are no data in healthy man regarding the contribution that the colonic mucosa makes to whole body protein synthesis.
▪ Previous investigations of protein metabolism in these clinical disorders have centred on measurements of whole body protein turnover.
■ NOUN
animal
▪ Licensed hawkers were circulating, braying the merits of spiced sausages containing only real animal protein - so they claimed.
▪ A recently proposed federal ban on feeding animal protein to animals is encouraging, writes Rhodes, but has too many loopholes.
▪ It can only obtain it by eating animal proteins.
▪ And mounting evidence shows diets high in animal protein trigger calcium loss from bones, increasing osteoporosis risks.
▪ This is just as beneficial as having animal protein.
▪ We have always assumed that animal protein was the necessary kind for human health.
▪ But one animal protein feed has been produced from bacterial synthesis using ammonia, methanol from North Sea gas and minerals.
▪ The tendency in the past has been to restrict or cut down on plant proteins and increase animal protein in the diet.
concentration
▪ Biliary protein concentration was similar between the two groups.
▪ The binding is reversible so that factors that decrease the protein concentration will increase the ionized fraction of calcium in the blood.
▪ Cholesterol nucleation time, biliary lipid concentration, vesicular cholesterol distribution, and biliary protein concentration were measured and compared.
▪ The total protein concentration did not differ between the two groups as shown by Yamazaki etal.
▪ The nucleation time did not correlate with either total lipid concentration or total protein concentration.
▪ All lysosomal enzyme assays were linear with respect to time and protein concentration.
▪ Tissue protein concentrations were determined by the method of Lowry etal.
▪ The oedematous patients had similar lung function, smoking histories, and plasma protein concentrations to the patients without oedema.
content
▪ The total protein content of the tube was evaluated by the Bradford protein method.
▪ The plant protein isolates are highest in protein content.
fusion
▪ Schematic representations of the fusion proteins and reporter gene that were used.
▪ The reciprocal combinations used provide an internal functional control for expression of the fusion proteins.
▪ These fusion proteins could be used similarly to screen expression libraries.
▪ Production and maintenance of Rat-1 fibroblasts stably expressing the c-Myc-ER fusion protein and the defective c-Myc mutant protein 106-143c-Myc-ER have been described.
kinase
▪ Association of a purine-analogue-sensitive protein kinase activity with p75 nerve growth factor receptors.
▪ Some forms of protein kinase C require Ca 2 + for activation.
▪ The site, or sites, at which protein kinase C exerts these inhibitory effects is unresolved.
level
▪ Equally conflicting results with regard to glycaemic control and platelet-specific protein levels have been reported in longitudinal studies.
▪ It is also apparent that multiple tenascin isoforms are detectable at the mRNA and protein level.
▪ In addition, the Ea transgene concentration at either message or cytoplasmic protein level, is apparently not toxic to the cell.
▪ These results lend support to the idea that tenascin alternative splice forms may also have functional significance at the protein level.
▪ It benefits your eyes by supplying more oxygen than normal lenses and also minimises protein levels, which prevents build up.
metabolism
▪ These studies of whole body protein metabolism, however, simply reflect an average of events occurring in all individual tissues.
▪ It also plays an important role in lipid, carbohydrate, and protein metabolism of adults.
▪ Powell-Tuck etal measured whole body protein metabolism in 19 patients with ulcerative colitis, while they were receiving enteral or intravenous nutrition.
▪ It is probably due to the accompanying impairment in protein metabolism.
▪ In addition, they extend the observations from whole body studies of protein metabolism that have been previously reported.
▪ Ammonia, the terminal product of protein metabolism, must be excreted rapidly and diluted to non-toxic levels in the surrounding fluids.
▪ Previous investigations of protein metabolism in these clinical disorders have centred on measurements of whole body protein turnover.
molecule
▪ They are smaller molecules than proteins, so they have to become attached to a protein molecule before they are activated.
▪ One experiment produced crystals of protein molecules that drug company researchers believe could advance the development of antiviral drugs.
▪ These slightly altered protein molecules are mass-produced by the protein-making machines inside the developing brain cells.
▪ The antibodies are protein molecules that can fit on to an allergen and inactivate it.
▪ Some protein molecules are simply too large for microbes to handle.
▪ Research has however shown that in terms of the arrangement of the protein molecules this model is no longer accurate.
▪ Synthesizing any new protein molecule from scratch takes a matter of minutes.
▪ Sometimes, different protein molecules will fit together, like the pieces of a three-dimensional jigsaw, to form larger-scale structures.
sequence
▪ Comparison between the protein sequences of Drosophila and rat ribosomal protein S2.
▪ Serratus is the most comprehensive, non-redundant protein sequence database available to the protein chemist.
▪ Cameleon provides a powerful interactive graphics interface to protein sequence homology modelling.
▪ It aligns two protein sequences interactively.
serum
▪ Based on the production of this absorption peak, it is possible to quantitate serum proteins by an ultraviolet-light technique.
▪ The other structural characteristic that may be used to quantitate serum proteins is the presence of peptide bonds.
▪ The buffer base is composed of the anionic buffers which include bicarbonate, phosphate, serum proteins, and hemoglobin.
▪ They are hemoglobin, serum protein, phosphate, and bicarbonate.
skimmer
▪ How do I determine the size of protein skimmer I need.
▪ Renewing the airstone Q. Adjusting my protein skimmer is causing me problems.
▪ Internal protein skimmers are determined by the depth of the tank.
▪ It has undergravel filtration run by two powerheads, with a protein skimmer.
▪ Use a Rena 301 to run the protein skimmer.
▪ Although U/V, ozone and protein skimmers were known, reference books often claimed they were unnecessary.
▪ Is this adequate, or should I add a protein skimmer and/or external canister filter?
▪ The tank has a protein skimmer.
synthesis
▪ The inhibitors might therefore be causing amnesia not because they prevent protein synthesis but because of their effect on increasing amino acid levels.
▪ Testosterone promotes protein synthesis and thus greatly increases physical strength.
▪ But exactly how viral protein synthesis is selectively inhibited, leaving cellular protein synthesis relatively unaffected, is still not clear.
▪ Measuring the rate of protein synthesis then becomes a matter of measuring the rate at which amino acids are incorporated into proteins.
▪ We repeated the experiments with a precursor for protein and found that an increase in protein synthesis occurred also.
▪ For example, when two amino acids are joined, as in protein synthesis, energy must be supplied.
■ VERB
bind
▪ As shown in Fig. 3, both oligonucleotides were able to bind F9 proteins and to produce retarded complexes.
▪ T3 and diffuse into the circulation where they are bound to proteins. 353.
▪ Some AEDs are more tightly bound to protein than others.
▪ In some tissues the action of calcium on adenylate cyclase is mediated by the calcium binding protein calmodulin { 19 }.
▪ The arms races between parasites and their hosts are all about these binding proteins.
contain
▪ Licensed hawkers were circulating, braying the merits of spiced sausages containing only real animal protein - so they claimed.
▪ Although guayule latex contains fewer proteins than hevea, manufacturers should still wash it well, Cornish said.
▪ This treatment contains protein and Vitamin E which help strengthen, moisturise and protect your hair.
▪ This burgeoning family now contains over 20 different proteins, principally identified through sequence homology.
▪ Repeating these steps produced a plasmid containing two protein A domains, and then by another step to one with three domains.
▪ Filtration in both tanks is undergravel, driven by powerheads and both contain protein skimmers.
▪ The band containing each protein was cut out and the gel was emulsified in Freund complete adjuvant for injection.
▪ Each rod contains thousands of proteins that transform light into signals via a molecule that crosses the membrane in a sevenfold zigzag.
encode
▪ The genes encoding the protein are packaged such that the encoded protein is displayed on the outside of the package.
▪ Therefore, the genes encoding these proteins were chosen for insertion into the triple gene transfer vector.
express
▪ At this stage the cells had already assumed an epithelial form, but were not yet expressing the two marker proteins.
▪ Electrophoretic mobility shift assays Oct-11 and Oct-2 proteins were expressed in E.coli as protein A-fusions.
▪ The vectors were utilized to express bluetongue virus proteins.
▪ Production and maintenance of Rat-1 fibroblasts stably expressing the c-Myc-ER fusion protein and the defective c-Myc mutant protein 106-143c-Myc-ER have been described.
produce
▪ One obvious approach is to look for genes that produce proteins similar to existing drug targets.
▪ These plasma cells produce a homogeneous immunoglobulin protein which stains as a well-defined peak in the gamma region.
▪ The process produces no new proteins, it only causes physical changes to existing structures.
▪ A normal gene produces a normal protein, then something goes wrong and the body starts turning out prions.
▪ The phase between divisions, when the genes produce proteins and the cell grows, is called interphase.
▪ Transgenic animals are genetically altered to produce proteins in their milk.
▪ Even worse, they produce proteins in large quantities which are very similar to those in our own body.
▪ Those genes would produce a harmless protein that, once inside the body, would sound the false alarm of infection.
provide
▪ Native grasses usually have insufficient nutritional value as they provide considerably less protein.
▪ This sample diet provides all the protein, carbohydrates and fats needed for a maximum muscle-building program for that 200 pound man.
▪ These should include snack foods providing vital proteins, carbohydrates, minerals, vitamins and fats.
▪ And a couple of times a year, they would slaughter the hogs or heifers that provided year-round protein.
▪ As a supplement, feeder shrimps will provide additional proteins and roughage.
▪ Enough grain is produced to provide everyone with ample protein and more than 3,000 calories per day.
show
▪ Tests in other transgenic plant species show that protein coats taken from viruses appear to confer protection against them.
▪ Here we show that the iron-free protein does not undergo any major structural changes compared with the iron-containing R2.
PHRASES FROM OTHER ENTRIES
animal products/fats/protein etc
▪ A recently proposed federal ban on feeding animal protein to animals is encouraging, writes Rhodes, but has too many loopholes.
▪ Cholesterol is found only in animal products, such as meats-especially organ meats-whole milk products and the yolk of eggs.
▪ In general, the consumption of animal products has decreased while the consumption of plant products increased during recent years.
▪ It can only obtain it by eating animal proteins.
▪ Licensed hawkers were circulating, braying the merits of spiced sausages containing only real animal protein - so they claimed.
▪ The method was designed to estimate the intakes of total and saturated fat, cholesterol, and animal protein.
▪ The sanctions could take the form of a ban on virtually all trade in wild animal products with the two countries.
▪ What animal products are used in other wines, and why are producers not obliged to list the ingredients?
EXAMPLES FROM CORPUS
▪ Although guayule latex contains fewer proteins than hevea, manufacturers should still wash it well, Cornish said.
▪ It can only obtain it by eating animal proteins.
▪ Kidneys clog with protein from damaged muscles, damming up toxins in the blood.
▪ Renewing the airstone Q. Adjusting my protein skimmer is causing me problems.
▪ The molecular identity of the 240K protein is not yet known.
▪ The second interferon-induced enzyme adds a phosphate group to a protein that is essential for the synthesis of new proteins to begin.
▪ Understanding the Role of Antibodies Antibodies are protein substances manufactured by the human immune system to help defend us against diseases.
The Collaborative International Dictionary
protein

Proteid \Pro"te*id\, n. [Gr. prw^tos first.] (Physiol. Chem.) an older, imprecise term replaced by {protein}.

Note: Defined in the 1913 Webster as ``One of a class of amorphous nitrogenous principles, containing, as a rule, a small amount of sulphur; an albuminoid, as blood fibrin, casein of milk, etc. Proteids are present in nearly all animal fluids and make up the greater part of animal tissues and organs. They are also important constituents of vegetable tissues. See 2d Note under Food.'' -- Pro"te*id, a.

Defensive proteid (Physiol. Chem.), one of a class of proteid substances, present in some animal tissues and fluids, that make the body immune to certain infectious diseases by destroying or rendering inactive the toxic products of bacterial growth; -- this is an older term replaced by more precise modern immunological concepts such as antibody and immunoglobulin. [archaic]

protein

macromolecule \mac`ro*mol"e*cule\, n. (Chem., Biochem.) A very large molecule, especially a polymer having from hundreds to many thousands of atoms, such as DNA, RNA, protein, polysaccharide, polyethylene, polycarbonate, etc.

Related phrases:
Douglas Harper's Etymology Dictionary
protein

1844, from French protéine, coined 1838 by Dutch chemist Gerhard Johan Mulder (1802-1880), perhaps on suggestion of Berzelius, from Greek proteios "the first quality," from protos "first" (see proto-) + -ine (2).\n

\nOriginally a theoretical substance thought to be essential to life, further studies of the substances he was working with overthrew this, but the words protein and proteid continued to be used in international work on the matter and also for other organic compounds; the modern use as a general name for a class of bodies arose in German. The confusion became so great a committee was set up in 1907 to sort out the nomenclature, which it did, giving protein its modern meaning and banishing proteid.

Wiktionary
protein

n. 1 (context biochemistry English) Any of numerous large, complex naturally-produced molecules composed of one or more long chains of amino acids, in which the amino acid groups are held together by peptide bonds. 2 (context nutrition English) One of three major classes of food or source of food energy (4 kcal/gram) abundant in animal-derived foods (qualifier: ie: meat) and some vegetables, such as legumes. ''see carbohydrate and fat for the other two major classes''

Related phrases:
WordNet
protein

n. any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes; "a diet high in protein"

Related phrases:
Wikipedia
Protein (band)

Protein was a punk, alternative, post-grunge, metal band formed in 1994 in San Francisco, California.

Forming their first band after they were kicked out of a San Francisco-area high school, vocalist/guitarist Josh Zee (the son of a professional folksinger) and drummer Dan Thompson played for several years in various local bands before forming the grungy alternative pop band Protein in 1994. The duo played several shows before replacing their part-time bassist with Russ Violet and made a good showing at a San Francisco music-industry showcase in 1996. Signed to Sony's Work subsidiary, Protein released their debut album, Ever Since I Was a Kid, which was released in 1997. A second album, Songs About Cowgirls, was released in 1999.

Protein (nutrient)

Proteins are essential nutrients for the human body. They are one of the building blocks of body tissue, and can also serve as a fuel source. As a fuel, proteins provide as much energy density as carbohydrates: 4 kcal (17 kJ) per gram; in contrast, lipids provide 9 kcal (37 kJ) per gram. The most important aspect and defining characteristic of protein from a nutritional standpoint is its amino acid composition.

Proteins are polymer chains made of amino acids linked together by peptide bonds. During human digestion, proteins are broken down in the stomach to smaller polypeptide chains via hydrochloric acid and protease actions. This is crucial for the synthesis of the essential amino acids that cannot be biosynthesized by the body.

There are nine essential amino acids which humans must obtain from their diet in order to prevent protein-energy malnutrition. They are phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine, lysine, and histidine. There are five dispensable amino acids which humans are able to synthesize in the body. These five are alanine, aspartic acid, asparagine, glutamic acid and serine. There are six conditionally essential amino acids whose synthesis can be limited under special pathophysiological conditions, such as prematurity in the infant or individuals in severe catabolic distress. These six are arginine, cysteine, glycine, glutamine, proline and tyrosine.

Humans need the essential amino acids in certain ratios. Some protein sources contain amino acids in a more or less 'complete' sense. This has given rise to various ranking systems for protein sources, as described in the article.

Sources of protein include grains, legumes and nuts, as well as animal sources such as meats, dairy products, fish and eggs. Vegetarians and vegans can get enough essential amino acids by eating a variety of plant proteins. It is commonly believed that athletes should consume a higher-than-normal protein intake to maintain optimal physical performance.

Protein (disambiguation)

Protein is an organic compound made of amino acids.

Protein may also refer to:

  • Protein (nutrient)
  • Protein (band)
Protein

Proteins ( or ) 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 molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific three-dimensional structure that determines its activity.

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 bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residues in a protein is defined by the sequence of a gene, which is encoded in the genetic code. In general, the genetic code specifies 20 standard amino acids; however, in certain organisms the genetic code can include selenocysteine and—in certain archaea— pyrrolysine. Shortly after or even during synthesis, the residues in a protein are often chemically modified by post-translational modification, which alters the physical and chemical properties, folding, stability, activity, and ultimately, the function of the proteins. Sometimes proteins have non-peptide groups attached, which can be called prosthetic groups or cofactors. Proteins can also work together to achieve a particular function, and they often associate to form stable protein complexes.

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 1–2 days in mammalian cells. Abnormal and or misfolded proteins are degraded more rapidly either due to being targeted for destruction or due to being unstable.

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 functions, such as actin and myosin in muscle and the proteins in the cytoskeleton, which form a system of scaffolding that maintains cell shape. Other proteins are important in cell signaling, immune responses, cell adhesion, and the cell cycle. In animals, proteins are needed in the diet to provide the essential amino acids that cannot be synthesized. Digestion breaks the proteins down for use in the metabolism.

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 structure and function include immunohistochemistry, site-directed mutagenesis, X-ray crystallography, nuclear magnetic resonance and mass spectrometry.

Related phrases:

Usage examples of "protein".

But he is not ready to tell Botkin or Koss the wildest of his suspicions: the double helix somehow codes not only for its own messenger, but also for the elusive adaptor, the ribosome assembly line, and all the enzymes needed to recognize the adaptor, affix the amino acids, promote the growing chain, and trim the finished proteins.

More properly known as gelatin hydrolysate, it is also used in shampoos and conditioners, lipsticks, protein drinks, arthritis relief formulas and many other products that Joe will never touch the rest of his life.

In short, I created a protein macromolecule that can be set on a definite course of development, as an alarm clock can be set.

One of the aims of the maltster is, therefore, to break down the protein substances present in barley to such a degree that the wort has a maximum nutritive value for the yeast.

Another bonus: Fish oil and fish protein have been shown to regenerate the membrane of the meniscus, which is important if you suffer a painful tear, or have chronic meniscus discomfort.

Now called metarhodopsin II, the protein sticks to another protein, called transducin.

No metabolic activity was detected in the Ceraunius forms, but electron microscopy reveals what appear to be cell walls, and RNA protein fragments within the forms.

A special cocktail of granulocytes, monocytes, lymphocytes and soluble proteins.

We must imagine the morphogenesis of deep structures, built into our minds, for coding out, like proteins, the parts of speech.

The protein roll bounced away and fetched up against the Parametric Laser housing.

Isoflavone-rich soy protein isolate attenuates bone loss in the lumbar spine of perimenopausal women.

In the normal individual, the amino acid phenylalanine, an essential constituent of proteins, is routinely converted in part to the related amino acid tyrosine, also an essential constituent of proteins.

There are a number of membrane proteins which can be phosphorylated in this way, some postsynaptic, some presynaptic, and the enzymes responsible for catalysing the phosphorylation are known collectively as protein kinases.

Ali, S M, Bullock, S, and Rose, S P R Phosphorylation of synaptic proteins in chick forebrain: changes with development and passive avoidance training.

The individual particles were extremely small, subject to damage from cosmic rays, photochemical decay, dehydration of their protein chains, and other environmental factors.