Amino Acid Protiens Flashcards
(25 cards)
what do amino acids have
two functional groups a carboxylic group and a primary amine
what are the difference in the functional group
one is an acidic fnctional group and the other is a basic functional group
what does carboxylic acid group do
has a tendency to donate a proton so act as an acid
what does the amine group have
the tendency to gain a hydrogen
what do they exist as and what does this mean
a switterion have permanent positive charge and a permanent negative charge but overall are neutral
because they are ionic what does this mean
they have a high melting point and dissolve well in water bt poorly in non polar solvents
what does it exist like in room temperature
it is a white solid and acts like an ionic salt
what happens in strongly acidic condition
the amine group accepts a hydrogen and become protonated
what happens in strongly alkaline conditions
the oh group loses a hydrogen and become deprotonated and form a negative ion
when an amide reacts with another amide what form
an amide linkage
what happens when a protein is boiled with hcl of 6 mol/dm3
it breaks down to a mixure of all its constituent amino acids that make up the original protein
how are protein shapes maintained
hydrogen bonds, vdw force, disulphide bridges
why do proteins shape need to be maintains
they are vital to functions such as enzymes and structure
what are the two secondary shapes that proteins form
proteins form alpha helix or beta sheets
what is wool
is a protein fibre with a helix that is held together by hydrogen bonds
what happens when wools is stretched
the hydrogen bonds stretch and the fibre extends
what happens when you release the tenision
allows the hydrogen bonds to return to their normal length and the fibre returns to its original shape
what does wahing at high temperatures do to wool
can permanently break the hydrogen bonds and the garment may lose its shape
where does the bonding exist between amino acids
between the c=o and the n-h
what is the primary structure of a protein chain
sequence of the relevant amino acids held together by covalent bonds so relatively stable
what is sencondry structure
3d shape held by hydriogen bonding and covalent bonds
why can this structure be changed easily
hydrogen bonds are much weaker than covalent bonds so the structure can be changes in temperature and ph
what is the tertiary structure
held together by a mix of hydrogen bonding ionic interaction and sulfur sulfur bonds forming globular shapes
how do we determine the shape of protiens
we use x ray diffractions which can locate the actual position of atoms in space
