T2.4 Proteins Flashcards
NOT DONE YET
What happens to form a peptide bond between the amino acids?
Like what type of reaction and where bond is formed
A condensation reaction that involves the amine group of one amino acid and the carboxyl group of another
OH is taken from carboxyl
H is from amine
Carbon in the carboxyl bonds with the nitrogen in the amine group
Link to video from Khan academy detailing peptide bond formation if ur confused
Dipeptide
Di = 2
2 amino acids joined together by peptide bond
Oligopeptide
Oligo = many
Fewer than 20 amino acids in the peptide
Polypeptide
More than 20 amino acids in the peptide
Function of R-groups
Give the amino acid its individual character
Equation for finding the possible amino acid sequences
20 to the nth power, where n is # of amino acids in the polypeptide and 20 is the constant amount of amino acids that can be in the organism
Ex, 2 amino acids in peptide, 400 possible amino acid sequences
Equation for finding the possible amino acid sequences
20 to the nth power, where n is # of amino acids in the polypeptide and 20 is the constant amount of amino acids that can be in the organism
Ex, 2 amino acids in peptide, 400 possible amino acid sequences
How many bases code for an amino acid in a polypeptide?
3 (codon)
remember the trauma from transcription and translation from last year
Ex: polypeptide with 400 amino acids should require a gene with 1,200 amino acids
What changes about the length of genes in practice?
Genes are typically longer. There are extra bases at each end and in the middle. This provides regulation of transciption and translation
Can proteins consist of more than one polypeptide?
yep
Example of protein with one polypeptide
Lysozyme - secretions in mucus and tears. Kills bacteria
Examples of proteins with multiple polypeptides
2 polypeptides: Integrin (membrane protein that makes connections with structures inside and outside of cell.
3 polypeptides: Collagen (protein that provides structure to tendons, ligaments, skin, etc)
4 polypeptides: Hemoglobin (protein that transports oxygen through blood
Conformation of a protein
its 3D structure
What determines the conformatin of a protein?
The amino acid sequence
Fibrous proteins
- enlongated with many repeating structures (sequences)
- Hydrophobic
- Structure proteins
Example and function of a fibrous protein
Either collagen or spider silk
Collagen - structural protein found in muscles, tendons and ligaments that gives tensile strength.
Spider silk - Produced by spiders for their webs, and can be extended and resistant to breaking.
Globular
- Glob like (spherical)
- Generally involved in metabolism or membrane proteins
- Soluble in water
How are globular proteins soluble in water?
The hydrophobic R groups on the amino acid chain are on inside the sphere while hydrophilic R groups are on the outside, allowing it to be soluble.
How are globular proteins membrane proteins?
cause they’re imbedded in the hydrophobic inside of the lipid bilayer
The hydphilic groups are inside the glob while the hydrophobic R groups are lining the channel.
Example of Globular proteins?
- Can be Rubisco, Insulin, Immunoglobulin, or Rhodopsin
- Rubisco - an enzyme involved in the fixation of CO2 in chloroplasts
- Insulin - a hormone produced by the beta cells of the pancreas, which is involved in glucose uptake from the blood
- Immunoglobulin (antibodies) - Large, Y-shaped proteins, involved in fighting infections by specifically recognizing and binding to antigen molecules
- Rhodopsin - A protien linked to pigment, found on the membrane of photoreceptor cells of the retina, where it allows very low light intensities to be detected
Honestly would just look at insulin since we’ve studied it before
Know at least 5 functions of proteins
- Catalysis (speeds up reactions)
- Muscle Constraction (actin/myosin used in locomotion),
- Cytoskeletons (give cells shape and aids in mitosis)
- Tensile strengthening (fibrous proteins give strenth to skin, tendons, ligaments, and blood vessel walls
- Blood Clotting (turns blood from liquid to gel)
- Transport of nutrients and gasses (Transports oxygen and carbon dixoide)
- Cell Adhesion (Cells stick together within tissue)
- Membrane Transport (Facillitated diffusion and active transport (channels and pumps))
- Hormones (Insulin, FSH, and LH)
- Receptors (Binding sites for hormones, neurotransmitters, etc)
- Packing of DNA (Histones in eukaryotic organisms)
- Immunity (antibodies)
make like a quizlet for the 5 u want to study
Genome
All the genes produced by a cell/tissue/organism
Fixed from cell to cell
Proteome
All the proteins produced a cell/tissue/organism.
Diverse
Changes overtime depending on cell activity
Why do protemes vary based on the cell?
Different cells in an organism make different proteins (cell differentiation)
What does the proteome reveal about a cell?
What is actually happening in a cell
How does the proteome of a species contain a larger number of proteins than genes that code for these proteins?
One gene can code for multiple polypeptide chains, so there are more proteins than genes coding for them