Proteins Flashcards
Major structural components of many natural foods, often determining their overall texture such as tenderness of
meat or fish products.
Proteins
Also known as polypeptides
Proteins
Proteins are organic compounds made up of —– —– arranged in a linear chain and folded into a globular form
Amino acids
Amino acids in a polymer are joined
together by the ——- —– between the —— and —– —- residues.
Peptide bonds
Carboxyl
Amino acids
How many types of amino acids occur
naturally in proteins?
20
Proteins differ from each other to the type, number and sequence of amino acids that make up the
Polypeptide backbone
Protein molecules range from the long, ——– —- that make up connective tissue and hair to the compact, ——- —— that can pass through cell membranes and set off metabolic reactions.
insoluble fibers
soluble globules
Types of Proteins
Example of this type of protein are
– Collagen, keratin, fibrinogen, muscle protein
Fibrous protein
can be obtained by boiling animal bones and connective tissue
Gelatin
purified form of gelatin is obtained
from ———— of the certain fishes
including sturgeon, cod, catfish and carp
Air bladders
What type of protein contain these examples — Albumin, globulin, casein, hemoglobin, all enzymes and hormones.
Globular Proteins
one of a class of simple
proteins, composed of C,H,O,N and
small amount of S.
Albumin
Globular proteins Forms insoluble compounds with many
metallic salts, such as —— of
mercury, —— of copper, and —– of
silver, and is, therefore, used as an
antidote to these poisons.
bichloride
sulfate
nitrate
Building blocks of proteins
Amino acids
Amino acids is composed of 3 groups
What are those?
Carboxylic Acid group
Amino group
And R group
Amino acids is composed of 3 groups
What are those?
Carboxylic Acid group
Amino group
And R group
are molecules containing an
amine group, a carboxylic acid group and a side chain that varies between different —— —–
Amino acids
The key elements of an amino acid are
carbon, hydrogen, oxygen, and nitrogen.
What type of proteins contain these examples tendons, cartilage, hair, nails?
Structural
Muscles
Contractile
Hemoglobin
Transport
Milk
Storage
insulin, growth hormone
Hormonal
catalyzes reactions in cells
Enzymes
Immune Response
Protection
10 amino acids not synthesized by the body
arg, his, ile, leu, lys, met, phe, thr, trp, val
Arginine
Histidine
Isoleucine
Lysine
Methionine
Phenylalanine
Threonine
Tryptophan
Valine
How many amino acids cannot be synthesized by the body?
10
R = H, CH3, alkyl groups, aromatic
Nonpolar
R = –CH2OH, –CH2SH, –CH2C–NH2
, ( groups with –O-, -SH, -N-)
Polar
R = –CH2COOH, or -COOH
Polar/Acidic
R = –CH2CH2NH2
Polar/Acidic
This type of amino acid
Must be obtain from the diet
• All in diary products
• 1 or more missing in grains and vegetables
Essential Amino Acid
What kind of bond is formed when the –COOH of an amino
acid and the –NH2 of the next amino acid bonded?
Amide (peptide) bond
Three-dimensional arrangement of amino acids with the polypeptide chain in a corkscrew shape
• Held by H bonds between the H of –N-H group
and the –O of C=O of the fourth amino acid along the chain
• Looks like a coiled “telephone cord”
Secondary Structure – Alpha
Helix
Polypeptide chains are
arranged side by side
• Hydrogen bonds form
between chains
• R groups of extend above and
below the sheet
• Typical of fibrous proteins
such as silk
Secondary Structure - Beta Pleaded Sheets
