lecture 6 part 1 Flashcards
prteins are
polymeric macromolecules composed of amino acids
subunit of proteins
amino acids
macromolecule of protein
protein
are proteins diverse in structure and function
yes
what is the most diverse macromolecule
proteins
what is the largest % of a cell’s dry weight
protein
proteins can be dynamic structures that move in response to what
binding by another moleq or specific environmental conditions
kinesin is
motor protein
suffix “ase” represents
enzyme
what is the structure (and this function) of a protein determined by
its amino acid sequence
-its amino acid determines the proteins 3D structure through their ability to form non covalent bonds (and sometimes covalent bonds)
defense proteins
-antibodies attack pathogens
-could be venoms/toxins that protect organisms from being eaten
storage proteins
-some proetsins store amino acids for later use
caesin
protein of mil, major source of amino acids for baby mammals (storage protein)
ovalbumin
protein of egg white, used as amino acid source for developing embryo (storage protein)
transport proteins
-mole moleqs from one side of a membrane to another or in and out of cell/organelle
-hormones (proteins)
-transceptors for protein is protein
motor proteins
-allow movement
-actin and myosin proteins = responsible for muscle contraction
proteins need different ______ to fulfill different duties
shapes
when does hemoglobin shape change
with removal of oxygen
what does kinesin need to operate to move
needs ATP and hydrolysis to operate to move, kinesin moves giant vesicle yo cell surface for expression
basic structure of amino acid has
amino group (NH2) and carboxyl group
how else can you draw basic structure of amino acid
as dipolar ion which is the typical form of an amino acid inside a cell or in blood
how many common amino acids are there
20
what are the four categories of amino acids
1)non polar side chains; hydrophobic
2)polar side chains; hydrophilic
3)electrically charged side chains; hydrophilic
4)acidic (negatively charged)
what can two cysteine residues form
a disulfide bond
disulfide bonds
covalent bonds and are therefore much stronger than an individual non covalent bond (such as a hydrogen bond)
what type of bonds form together amino acids
peptide
peptide is
a few amino acids joined together
polypeptide
many amino acids joined together
what are peptide bond formation catalyzed by
ribosomes within a cell
what rxn breaks peptide bond
hydrolysis rxn
hydrolysis rxn that reak peptide bonds are catalyzed by enzymes called
proteases and peptidases
