protein synthesis and functions Flashcards
what is histatin
peptide
what do fibrous proteins provide
mechanical support
what are proteins
molecules that perform all functions required for life
describe globular proteins
water soluble
many functions
what are proteins made from
amino acids
20 commonly found
9 derived from diet - essential amino acids
c
primary
secondary
tertiary
quaternary
what are amino acids joined by
peptide bonds
what type of protein is collagen
structural
function of collagen
provide support to extracellular space of connective tissues
what does a lack of vitamin c lead to
scurvy
associated with gum disease + skin problems
what does proline being modified to hydroxyproline make + require
triple helix
requires vitamin c
describe amylase
most abundant protein in saliva
hydrolyses carbs
part of acquired enamel pellicle - facilitates bacterial attachment to teeth
what is catalysis
speeding up reaction
what does amylase hydrolyse
carbs
long chains into shorter chains
what is histatin important for
essential for host defence
why is histatin effective at killing bacteria
va
what level of folding does haemoglobin have
quaternary
function of haemoglobin
transport oxygen in the blood stream
what might amino acid changes lead to in haemoglobin
inability to carry oxygen
-sickle cell anaemia
what happens when proteins go wrong
genetic sequence changes - protein might not get made at all - premature stop codon or mis-sense shift in codons
does get made but shape is incorrect - can be removed by protein recycling machinery - proteasome
describe regulation
at initiation proteins can prevent binding of mRNA to ribosome
lack energy
many clinically effective antibiotics work by specifically inhibiting protein synthesis in prokaryotes
why might the cell lack energy in regulation
due to stress
what does translation do
make proteins
describe translation
genetic material stores the library of info on how a cell should function
included protein coding DNA sequences - transcribed to RNA
mRNA then translated to make protein