In this lecture you will learn:
Proteins are the product coded for by DNA. They have two functions, as enzymes and as structure (muscles). They are created from amino acids by dehydration synthesis. As they are made they become functional by folding into secondary, tertiary and even quarternary forms. In addition to folding, proteins can undergo other post translation modifications which can give them different functions (next lecture).
|An amino acid:
-- an alpha carbon to which are covalently bound:
– an amine group (- NH2)
– a carboxyl (acid) group (- COOH)
-- a side chain (R group) one of 20 different ones
– only twenty different amino acids are used to make PROTEINS
|- Two amino acids are covalently bonded
together to form a peptide/protein by a reaction that removes a molecule
of water. This reaction is called DEHYDRATION SYNTHESIS.
- The linkage is called a peptide linkage
or peptide bond
GO HERE to see dehydration synthesis of amino acids
"Titin, also known as connectin is a protein
.... is important in the contraction of striated muscle tissues. It consists
of 34,350 amino acids and the gene for titin also contains the largest
number of introns (363) ever discovered in any single gene."
"Albumin consists of 584 amino acids and
contains no carbohydrate. Serum albumin is the most abundant blood plasma
protein and is produced in the liver and forms a large proportion of all
plasma protein. The human version is human serum albumin, and it normally
constitutes about 60% of human plasma protein."
|EXCELLENT SITE HERE
THAT EXPLAINS PHOBIC AND PHILIC WITH NICE ROLLOVER FUNCTION
2. Some have charged side group and interact with water or are hydrophilic
3. Some are acidic (have COOH groups) like glutamic acid
4. Some have amino groups (NH3+)
5. Some have alcohol -OH groups
6. Some are neither hydrophobic nor
hydrophilic, but are in between.