polypeptide
Quick Summary
A polypeptide is a chain of amino acids linked by peptide bonds. While the distinction between peptides and proteins can be imprecise, polypeptides are generally considered to be longer chains of amino acids than peptides, typically consisting of 50 or more amino acids. Proteins are essentially very large peptides, formed from one or more polypeptide chains. These chains are fundamental to all living organisms and carry out essential biological functions. The specific sequence and arrangement of amino acids determine a protein's structure and function.1234
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gastrin…a 14-, 17-, and 34-amino-acid polypeptide. These forms are produced from a series of enzymatic reactions that cleave the larger proteins into their smaller forms.
Read More…a 14-, 17-, and 34-amino-acid polypeptide. These forms are produced from a series of enzymatic reactions that cleave the larger proteins into their smaller forms.
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geneGene transcription and translation…sequence of nucleotides forms a polypeptide chain; all proteins are made from one or more linked polypeptide chains.
Read More…sequence of nucleotides forms a polypeptide chain; all proteins are made from one or more linked polypeptide chains.
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bloodPlasma…acids are released from the polypeptide chains and are absorbed. The amino acids are transported through the plasma to all parts of the body, where they are taken up by cells and are assembled in specific ways to form proteins of many types. These plasma proteins are released into the…
Read More…acids are released from the polypeptide chains and are absorbed. The amino acids are transported through the plasma to all parts of the body, where they are taken up by cells and are assembled in specific ways to form proteins of many types. These plasma proteins are released into the…
Read More- bloodHemoglobin
…protein; a molecule contains four polypeptide chains (a tetramer), each chain consisting of more than 140 amino acids. To each chain is attached a chemical structure known as a heme group. Heme is composed of a ringlike organic compound known as a porphyrin, to which an iron atom is attached.…
Read More…protein; a molecule contains four polypeptide chains (a tetramer), each chain consisting of more than 140 amino acids. To each chain is attached a chemical structure known as a heme group. Heme is composed of a ringlike organic compound known as a porphyrin, to which an iron atom is attached.…
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human geneticsThe genetics of antibody formation…molecule consists of several different polypeptide chains—the light chains (L) and the longer heavy chains (H). The latter determine to which of five different classes (IgM, IgG, IgA, IgD, or IgE) an immunoglobulin belongs. Both the L and H chains are unique among proteins in that they contain constant and…
Read More…molecule consists of several different polypeptide chains—the light chains (L) and the longer heavy chains (H). The latter determine to which of five different classes (IgM, IgG, IgA, IgD, or IgE) an immunoglobulin belongs. Both the L and H chains are unique among proteins in that they contain constant and…
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immune systemBasic structure of the immunoglobulin molecule…molecular structure, consisting of four polypeptide chains. Two of the chains, which are identical in any given immunoglobulin molecule, are heavy (H) chains; the other two are identical light (L) chains. The terms heavy and light simply mean larger and smaller. Each chain is manufactured separately and is encoded by…
Read More…molecular structure, consisting of four polypeptide chains. Two of the chains, which are identical in any given immunoglobulin molecule, are heavy (H) chains; the other two are identical light (L) chains. The terms heavy and light simply mean larger and smaller. Each chain is manufactured separately and is encoded by…
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proteinThe amino acid composition of proteinsProteins are macromolecular polypeptides—i.e., very large molecules (macromolecules) composed of many peptide-bonded amino acids. Most of the common ones contain more than 100 amino acids linked to each other in a long peptide chain. The average molecular weight (based on the weight of a hydrogen atom as 1)…
Read MoreProteins are macromolecular polypeptides—i.e., very large molecules (macromolecules) composed of many peptide-bonded amino acids. Most of the common ones contain more than 100 amino acids linked to each other in a long peptide chain. The average molecular weight (based on the weight of a hydrogen atom as 1)…
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