Unit 2: Chem of Amino Acids, Peptides and proteins Flashcards
S:35
_______ is a monomeric unit of peptides and proteins
amino acids
- mosty occurs as a L- alpha amino acid
what does pKa mean?
when 50% of the functional group has H+ and 50% doesn’t have H
most amino acids occur as ___ amino acids
L alpha amino acids
what is the alpha carbon?
The carbon that the primary functional group binds to
_____ pKa means that there is a lot of H in the environment and the carbon will hold onto the H
Low pKa
____ pKa means that there is not a lot of H in the environment and the fxn group will donate a H
High pKa
Phe
Phenylalanine
Val
Valine
Thr
Threonine
Trp
tryptophan
Ile
Isoleucine
Met
Methionine
His
Histidine
Arg
arginine
Leu
Leucine
Lys
Lysine
PVT
essential amino acids
Phe - phenylalanine
Val - Valine
Threonine - Threonine
TIM
essential amino acids
Trp - Tryptophan
Ile - Isoleusine
Met- Methionine
HALL
essential amino acids
His- Histidine
Arg - arginine
Leu - Leucine
Lys- Lysine
What two amino acids are not required for protein synthesis ?
are they essential or non essential?
Hyl - hydroxylysine
Hyp- hydroxyproline
name the 5 aliphatic amino acids
- Which are non essential
Gly- non
ala - Non
val
leu
Ile
Name the 5 amino acids with hydroxyl fxn groups
- which are essential
Thr - Essential
Ser
Tyr
Hyl
Hyp
Name the two amino acids with sulfer fxn group
- which is essential
Cys
Met - Essential
Name the 4 amino acids with a carboxylic/ amide
Asp
Glu
Asn
Gln
(all are non-essential
Name the 4 basic amino acids
- which is non essential
Lys
arg
His
Hyl - non essential
Name the 4 aromatic amino acids
His
Phe
Trp
Tyr- non-essential
what is a pyrrolidine functional group ?
cyclic amine (CH2)4NH
Name the 2 amino acids with an pryrrolidine functional group
Pro
Hyp
What is the intermediate / amino acid required for Met
homocysteine
- fxn with B12
High levels ass. with atherosclerosis
High levels of _____ are ass. with atherosclerosis
homocysteine
What vit. does homocysteine fxn with?
B12
3 intermediates in biosynthesis of urea
ornithine
citrulline
argosuccinic acid
Ornithine is an intermediate for synthesis of _____
synthesis of urea
citrulline is an intermediate for synthesis of ____
urea
arginosuccinic acid is an intermediate for synthesis of
urea
____ is used as a drug for parkinsons disease
L-DOPA
L-DOPA is a precursor for biosynthesis of _____
catecholamines
Name the three most abundant catecholamines
epinephrine
norepinephrine
dopamine
Phenylalanine will produce ____
tyrosine
Tryosine is a derivative of _____
phenylalanine
essential to make a non essential
Cathechol decarboxylates to form _____. And is no longer an amino acid then
cathecholamine
Cathecholamine is a derivative of ____ that underwent decarboxylation
cathechol
_____ horm increases BMR, protein synthesis and cell proliferation
thyroid hormine
name the 2 precursors to make thyroid hormone
3-monoiodotyrosine
3,5-diiodotyrosine
(need iodine to make thyroid)
what non essential amino acid is the base for iodination to make thyroxine
tyrosine
_____ makes vit B5
B-alamine
_____ helps with the integrity and fxn of the retina
taurine
-beta amino acid
______ helps to make bile
taurocholic
taurocholic’s base is ___
taurine
Gamma-amnobutyric acid is also known as ____
GABA
____ inhibites neurotransmitters from glutamate
GABA
BABA inhibites neurotransmitters from ___
glutamate
_____ means that the molec. are mirror images of each other
enantiomers
A chiral molec that deflects polarized light to the left is caled ______
levorotatory (l or - )
A chiral molec that deflects polarized light to the right is caled ______
dextrorotatory ( d or + )
_______: molec that possesses both pos. and neg charges
Zwitterion
- amino acids can have both a + / - charge
at low pH: there is more ___ charge
( + )
- there is more H+ around in the enviro. so molec. wont donate it
at high pH: there is more ___ charge
(-)
- there is not a lot of H in the enviro., whats to donate it
polar molec. are hydro___
hydrophilic
polar molec are hydrophilic and can make ___ or ____ bonds
ionic or hydrogen bonds
Non-polar molec. are hydro____
hydrophobic
- they do not have ionic charges
If the R-group of an amino acid are aromatic they ahve strong ___
UV absorption
If an R- group of an amino acid are -OH they can become esterified by _____.
phsphorylation
alters the protein fxn
If R-group of amino acid are -SH they oxidize to form _______ bonds
disulfide
Disulfide bonds are usually formed btw two _____ (amino acid)
cysteine
non-essential amino acid
Disulfide bonds involved in redox rxn of ____
antioxidants
what does HbAc mean?
Hemoglobin adult, one carbohydrate
-OH or -NH2 can form glycoproteins by covalently bonding carb _____ bonds
glycosidic bonds
: covalent bond that joins carb molec to another group
___: the rxn in which a carb is attached to a -OH or other fxn group
glycosylation
glycohemoglobin means : _____
this is seen in what c.c.?
high levels of blood flucose levels
- diabetes
glycohemoglobin is formed by ____ bonds
glycosidic bonds
peptides are less then _____ amino acids
10
polypeptides are more then ____ amino acids
10
Proteins are comprised of many ____
polypeptides
Glutathione is a tripeptide made up of ___,__& ____ a.a.
Glu
cys
gly
Glutathione (GSH) is a peptide. Its fxn is ___
intracellular antioxidant
Peptide substance P is a ______
pain neurotransmitter
______: is an 11 a.a peptide in the gut, SC and brain
Substance P
_____: is a vasodilating polypeptide
kinins (bradykinin & kallidin)
_____ is a vasodilator polypeptide that is derived from proteolytic cleavage
kinin
_____: is the breakdown of proteins into smaller polypeptides or a.a.
Occurs by the hydrolysis of the peptide bond,
Proteolysis
- breaking off the inactive part
Name 3 opiopeptides
- enkaphalins
- B-endorphin
- Dynorphin
_____: have analgesic actions like opiates
opiopeptides
____ is an opiopeptide in the SC
dynorphin
_______ structures dictates specific a.a. sequences
primary structures
______ structure describes the 3-D structure of protein
tertiary structure
Fxn of Hb
transportation of O2 and CO2
buffers
a2B2 is a ___ HbA
adult
a2y2 is a _____HbA
y=gamma
fetal
What are three structures on Hb that bind O2
- Fe
- His (F8)
- His (E7) –> hinders Co binding
R-form of Hb binds to ____
O2
T-form cannot bind to _____ but can bind to _____
cannot bind to O2
Can bind to CO2
Ex of _______: binding of first O2 takes the longest. The rest gets progressively faster. bc the binding O2 changes conformation of other subunits
cooperative allosterism
What is the hemoprotein found in M.
myoglobin
O2 bound to ____ is a reserve for when pO2 of tissue is low . It then releases for AT synthesis
myoglobin
______ is the most abundent protein in the body
collagen
_____ is the most abundant aa in collagen, with lots of ___ &_____
glycine
lots of : proline and lysine