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Found Polypeptide 86 times.

Displaying results 1 to 10.

1. Alpha helix
This helical, usually right-handed arrangement of a polypeptide chain is a common secondary structure in protein s. The helix has maximal intrachain hydrogen bonding .

2. Alpha thalassemia
One of two major types of thalassemia , a genetically inherited disease, in which one of the two types of polypeptide s making up the hemoglobin protein is defective or missing. Hemoglobin proteins are composed of four polypeptides -- two "alpha chains" and two "beta chains". In alpha thalassemia, the alpha chains are defective or missing (see also beta thalassemia ). This disease mainly affects individuals of Southeast Asian, Chinese, and Filipino ancestry; in its most severe form it results in the death of the fetus or newborn. Individuals with less severe cases have varying degrees of anemia .

3. Amino acid sequence
Also known as the primary structure of a protein/polypeptide; the sequence of amino acids in a protein/polypeptide controlled by the sequence of DNA bases.

4. Amino terminal (amino terminus)
The end of a polypeptide chain with the unattached amino group (-NH2 group). Each amino acid in the chain has an amino group on one side (which is attached to the carboxyl group (a -COOH group) of the previous amino acid) and a carboxyl group on the other side (which is attached to the amino group of the next amino acid). The other end of the polypeptide chain is called the carboxyl terminal .

5. Aminopeptidase
This is an enzyme that sequentially cuts (via hydrolysis ) the peptide bonds from the N-terminus of a chain of polypeptide s. This sort of enzyme is known as an exopeptidase.

6. Amino-terminal residue
The only amino acid residue in a polypeptide chain that has a free alpha-amino group; it defines the amino terminus of the polypeptide.

7. Anticodon
A sequence of three nucleotides on the transfer RNA molecule that recognizes and pairs with a specific codon on a messenger RNA molecule; helps control the sequence of amino acids in a growing polypeptide chain.

8. Antienzyme
A protein or polypeptide that inhibits or destroys and enzyme .

9. Beta conformation
A polypeptide chain (often a secondary structure of a protein) arranged as a long zig-zag.

10. Beta thalassemia (Cooley's anemia)
One of two major types of thalassemia , a genetically inherited disease, where one of the two types of polypeptide s making up the hemoglobin protein is defective or missing. Hemoglobin proteins are composed of four polypeptides -- two "alpha chains" and two "beta chains". In beta thalassemia, the beta chains are defective or missing (see also alpha thalassemia ). The three classifications of beta thalassemia, in order of increasing severity, are thalassemia minor, thalassemia intermedia, and thalassemia major. Thalassemia major is also known as Cooley's anemia. Symptoms include slow growth, jaundice , enlarged heart, liver, and spleen , thinned bones. Untreated children die young, usually of heart failure or infections. Thalassemia intermedia produces milder symptoms for the first two decades of life in most cases. Thalassemia minor may not produce any symptoms, though changes in the blood occur.


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