Protein Functions
Enzymes- Catalysts
Structural- support and shaper
Motility- contraction and movement of cells and intracellular needs
Transport-ovement of other substances into and out of and within cell
Hormonal- immediate communication between cells in distant parts of
Dehydration Synthesis
The process of stringing individual amino acids together into a linear polymer.
As the three atoms of H2O are removed the carboxyl carbon of 1 amino acid and the amino nitrogen of a second are linked directlyThe process of stringing individual amino acids
Peptide Bond
Covalent C-N bond linking two amino acids
N-Terminus
A Chain of amino acids has an intrinsic directionality because it always has an amino group at one end and carboxyl group at the other end. The end with Amino group is N-Terminus
C- Terminus
End of amino acid chain that ends with carboxyl group
Polypeptide
Immediate product of amino acid polymerization. Has unique, stable, three-dimensional snap and is biological active. Some consist of single, and their shape is due to the folding and coiling that occur spontaneously as the chain is formed. Both a polymer
Monomeric Protein
Single polypeptide
Multimeric protein
Consist of two or more polypeptides that are often called polypeptide subunits.
if composed to two it is referred to as a dimer
If composed of 3 timer
If composed of 4 tetramer
Hemoglobin
/multimeric protein compose of four subunits two alpha and two Beta changes. Each subunit contains a heme group with a iron atom that can bind a single O molecule. iron attachment is known as a prosthetic group.
Conformation
Initial folding depends on several different kinds of bonds and interactions, including the covalent disulfide bond and non covalent interactions, including Hydrogen bonds, ionic bonds, Van der Walls and hydrophobic interactions.
Amino Acid Residue
Interactions for conformations, actions involve the carboxyl, amino and R groups of amino acids.
Disulfide bond
Forms between the sulfur atoms of two cysteine amino acids residues. these become covalently linked following oxidation reaction that removes 2 H from sulfhydryl groups. Covalent bond
Intramolecular bonds
stabilize the conformation, within one peptide
Intermolecular bonds
between two peptide chains
insulin
Dimeric protein inter linked
Primary
Formal designation. The order which appears from one end to the other. N to C terminus. Important for genetic and structure.
secondary
Common. Describes local regions that results from hydrogen bonds between NH and CO groups. forming alpha and beta sheets .
Tertiary structure
Final Folding. Comes about because of properties of R groups . Neither respective or predictable., complex globular shape, due to interactions between R-groups, such as hydrophobic interactions, van der Waals interactions, hydrogen bonds, and disulfide br
Quaternary Structure
Two or more interact, Highest level of organization occurring when protein contains more than one polypeptide chain. Interactions creating a functional protein; coded by genes and amino acids; three dimensional arrangement
alpha helix
3.6 amino acids per turn. Repeating polymers. peptide bonds form on the fourth amino acid. Every peptide is bonded CO group by hydrogen bonds to peptide bond directly below it. NH directly above it. Intramolecular.
Beta sheet
This structure is extented sheets with sucessive atoms in peaks and troughs of pleats . The R groups of amino acids jut out on alternating sheets . Intramolecular or intermolecular
Motif structure
units of secondary structure consisting of small segments of alpha and beta connected to each other looped regions of varying length., a cluster or grouping of secondary structural units present in many proteins that serve a similar function. ex: The heli
Fibrous Proteins
collagen, elastin, keratin. All have secondary structure throughout molecule giving them a highly ordered repetitive structure.
Globular Proteins
Most proteins involved in cellular structure are globular proteins. Named because their polypeptide chains are folded into compactsturctures rather than extended filaments. , These proteins are small spheres with little to no water inside. They have hydro
Domain protein
A defined region of a protein with a distinct structure and function; determined by the 3-dimensional shape of the region. They are discrete, locally folded units that typically includes 50 to 350 amino acids. Proteins with multiple functions will usually
Ribose
A five-carbon monosaccharide found in RNA, has one more oxygen atom than the other sugar associated with nucleic acids.
Deoxyribose
Five-carbon sugar that is a component of DNA nucleotides, having one fewer hydroxyl group than ribose, the sugar component of RNA nucleotides.
Purines
The family of larger nitrogenous bases in which its members have a six-membered ring fused to a five-membered ring; members are adenine (A) and guanine (G)
Pyrimidine
a nitrogenous base that has a single-ring structure; one of the two general categories of nitrogenous bases found in DNA and RNA; thymine, cytosine, or uracil
Adenosine Monophosphate
also known as 5'-adenylic acid, is a nucleotide that is found in RNA. It is an ester of phosphoric acid and the nucleoside adenosine. AMP consists of a phosphate group, the sugar ribose, and the nuclease adenine.as one phosphate group, chemical bond doesn
Adenosine diphosphate
molecule produced when adenosine triphosphate loses a terminal phosphate; ADP, molecule formed from the breaking off of a phosphate group from ATP, results in a release of energy that is used for biological reaction
Adenisine triphosphate
this is the most important biological molecule that provides chemical energy.
Structure of Nucleotide
phosphate group, 5 carbon sugar, nitrogenous base, made of sugar plus base on 1' carbon, plus phosphate group on 5' carbon, which is out of ring, and an OH on 3' carbon. a nucleoside is just a base plus sugar. As a free nucleotide, there are 2 phosphate g
Polysaccharides
A molecule formed by joining many monosaccharides together. Polysaccharides are typically energy-storage molecules (glycogen in animals, starch in plants) or structural molecules (cellulose in plants, chitin in exoskeletons). Long chained polymers of suga
Monosaccharide
The simplest carbohydrate, active alone or serving as a monomer for disaccharides and polysaccharides. Also known as simple sugars, the molecular formulas of monosaccharides are generally some multiple of CH2O. Can be defined as a aldehyde or ketone that
Carbohydrate
Formula CnH2nOn
, a class of energy giving nutrients that invcludes sugars, starches, and fiber; composed of one or more simple sugars bonded together
Diasaccharides
A sugar molecule consisting of two monosaccharides linked by dehydration synthesis. Maltose, Lactose, Sucrose and Fructose.
D glucose
Only one set of these isomers exists in nature, those derived from the "right-handed form" of glucose, denoted D-glucose. D-glucose is sometimes referred to as dextrose, although the use of this name is strongly discouraged. The term dextrose is derived f
Glycosidic bond
This reaction between the hydroxyl group of the first-position carbon and the hydroxyl group of the fourth position carbon of each monosaccharide. The covalent bond formed when carbohydrate molecules are joined together in condensation reactions
Starch
polysaccharide in plant cells that consists entirely of glucose monomers, storage in plant cells
Glycogen
An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch.
Cellulose
A structural polysaccharide of cell walls, consisting of glucose monomers joined by b-1, 4-glycosidic linkages.
Chitin
complex carbohydrate that makes up the cell walls of fungi; also found in the external skeletons of arthropods.
Lipids
nonpolar molecules that are not soluble or mostly insoluble in water. High molecular weights and their presence is very important to cellular structure, particularly membranes.
Fatty Acids
long chains carbon chains with hydrogen atoms attached. carboxylic acid group; the carboxyl end accociates with water molecules-hydrophilic portion; hydrocarbon tail is hydrophobic. Amphipathic. Energy rich found in Tricylglycerols. Fats, oils and found i
Classes of Lipids
Fatty Acids,Triacylglycerols, Phospholipids, Glycolipids, Steroids, Terpenes
Triacylglycerols
a family of lipids composed of three fatty acids bonded through ester bonds to glycerol, a trihydroxy alcohol. Formed stepwise with one fatty acid added at a time. Each fatty acid is linked to a carbon atom by means of condensation reaction.
glycerol
Three-carbon compound with three hydroxyl groups; component of fats and oils.
Phospholipids
a lipid made up of glycerol joined to two fatty acids and a phosphate group. The hydrocarbon chains of the fatty acids act as nonpolar, hydrophobic tails, while the rest of the molecule acts as a polar, hydrophilic head. Phospholipids form bilayers that f
phosphoglyerides
Type of Phospholipid with a glycerol backbone
Glycolipid
lipid in plasma membranes that bears a carbohydrate chain attached to a hydrophobic tail. may contain one to six sugar units. Hydrophilic of carb group gives it an amphipathic nature. Found commonly in nervous system
Steroids Lipid
Subunit: 4 fused carbon rings
Function: Membranes; hormones
Example: Cholesterol; Estrogen
Terpenes
Synthesized from five-carbon compound isoprene and also called isoprenoids. Joined to form Vitamin A , these lipids are comprised of long-chain hydrocarbons derived form a common, five-carbon subunit. They have diverse functions and include molecules such