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Related to proteins: Amino acids


Large molecules consisting of up to thousands of AMINO ACIDS linked together by peptide bonds to form polypeptides which, in turn, are linked to form proteins. These long chains of amino acids are often folded in specific ways. Fibrous proteins, such as COLLAGEN, are formed from spiral strand polypeptides. They are insoluble and constitute much of the structure of the body. Globular proteins are soluble and include the ENZYMES, many of the hormones and the blood proteins such as haemoglobin and the IMMUNOGLOBULINS (antibodies). Conjugated proteins contain other constituents such as sugars (glycoproteins) and lipids (lipoproteins). See also ABC TRANSPORTER PROTEINS, ACTIN BINDING PROTEINS, ACUTE PHASE PROTEINS, ALPHAFETOPROTEIN, AMYLOID, AMYLOID PRECURSOR PROTEIN, ANNEXINS, ANTIBODY, CHAPERONES, CHEMOKINES, COMPLEMENT, CONFORMATIONAL EPITOPE, CORE OCTAMER, CYTOKINES, DENATURATION, ELASTINS, FIBROBLAST, GLUTEN, GLYCOPROTEINS, G PROTEINS, GRANINS, HEAT-SHOCK PROTEINS, INTERMEDIATE FILAMENT PROTEINS, KERATIN, LECTINS, LIGAMENTS, LIPOPROTEINS, MEMBRANE-PROTEIN ION CHANNELS, MOTOR PROTEINS, MUSCLE, PLASMA PROTEINS, POLYMER, PRION PROTEINS, PROTEASE, PROTEIN BINDING, PROTEIN FOLDING, PROTEIN SYNTHESIS, REPRESSOR PROTEIN, RNA, SINGLE STRAND BINDING PROTEINS, TAU PROTEINS, TERTIARY STRUCTURE AND UBIQUITIN.


large polymers consisting of one or more sequences of amino acid subunits joined by peptide bonds: the major functional and structural components of body cells. The body of a 70 kg man contains about 11 kg protein. The protein mass can be influenced by nutritional status, physical activity and pathological factors. Proteins in the diet typically account for 10-15% of energy intake and the currently recommended protein requirement for sedentary individuals is 0.8 g per kilogram body mass per day. The optimal protein intake for strength athletes may be as high as 1.7-1.8 g and for endurance athletes 1.2-1.4 g per kilogram body mass per day. See also nitrogen balance.

proteins, macromolecules made of up of amino acids joined by peptide linkages and that provide essential life functions. Major sources of dietary proteins include meat, fowl, fish, eggs, beans, seeds, nuts, legumes, and dairy products.

Patient discussion about proteins

Q. I get about 190 grams of protein a day. Is that too much protein? Have you ever seen a guy living only for food? No? Here I am. I get about 190 grams of protein a day. Is that too much protein? My weight is 183 pounds.

A. this is a good amount, just make sure that you get the majority of it from real foods and not from powders and bars.

Q. Does the cooking have a negative effect on the protein content of the food? I have heard that high temperatures cooking breaks the protein, so does the cooking have a negative effect on the protein content of the food?

A. Yes. Proteins can be denatured by heat, but only when the protein structure is delicate or is exposed to extremely high temperatures for long time. You must remember that breaking of protein is the physical-chemical process where the physical or chemical structure of a protein is rearranged. So cooking will not reduce on the nutritive value of the food until it’s cooked at cooking temperatures.

Q. Is it true that Casein protein can cause Cancer, or is harmful to the human body? Someone left a comment on my blog about Casein protein being bad for the body and that it could lead to Cancer. Is this true?

A. I am not familiar with such information, Casein is a protein that is found in large amounts in breastmilk and milk products replacements for babies and as far as I know it has no such affect.

More discussions about proteins
References in periodicals archive ?
In influenza viruses, the nonstructural protein 1 inhibits the interferon-mediated antiviral response.
Generally, proteins change quite a lot on their surface when you go across different species," Mills says.
Using the AFM, biophysicists are finally answering basic and longstanding questions about proteins, from how they fold to how they break.
We feel that the PLK1-B23 phosphorylation story nicely demonstrates the power of the Kinetworks(TM) approach to rapidly and cost-effectively discover protein kinase drug targets and the means to identify their inhibitors" said Dr.
A final group of chapters is devoted to the functional value of proteins and how they are used as additives in foods.
Association of dietary protein intake and microalbuminuria in healthy adults: Third National Health and Nutrition Examination Survey.
The joint x-ray-NMR refinement can resolve structural ambiguities encountered in studies of multi-domain proteins, in which low- to medium-resolution diffraction data can be complemented by higher resolution NMR data obtained for the individual domains.
On the recovery side, forget it, there is no way that rapid and complete recovery can occur through the use of dietary protein.
A proprietary test strip and reagent solutions have been developed such that when a 1 [mu]l protein solution is applied onto the test strip, it produces compact and symmetrical protein spots (figure 1).
The report assesses the overall protein therapeutics market, key classes, and the factors influencing their historical and future performance.
Based on the reported sequence, an ORF is present from nt 90 to 1133, and the theoretical translation of this ORF yields a protein with homology to paramyxovirus P proteins but which is shorter than reported P proteins.
The proteins coming from a specific tissue, cell, or cellular component are separated before they are identified using MS.