biomolecules + metabolic biochemistry Flashcards
What is the molecular formula of glucose?
C₆H₁₂O₆
What does saccharide mean?
sugar
monosaccharides
basic unit of carbohydrates made of C, H + O in the ration 1:2:1
Give some examples of monosaccharides.
1) glucose
2) fructose
3) galactose
What is the general formula of monosaccharides?
(CH₂O)ₙ where n = 3/5/6
triose
when n=3
pentose
when n=5
hexose
when n=6
Give some examples of disaccharides.
1) sucrose (glucose + fructose)
2) lactose (galactose + glucose)
How are disaccharides formed?
a condensation reaction between 2 monosaccharides
glycosidic bond
bond that links 2 sugar molecules
Give an example of a polysaccharide.
glycogen
condensation polymerisation
a series of condensation reactions, adding one unit after another to the chain until very large molecules are formed
What is glycogen made up of?
subunits of glucose
What do the properties of a polysaccharide molecule depend on?
1) length
2) extent of branching
3) folding
4) whether the chain is straight/coiled
glycerol + 3 fatty acids/acyls =
triacylglycerol
saturated fat
saturated with hydrogen atoms
unsaturated fat
C=C bonds within the fatty acid chain
monounsaturated fat
single double bond
polyunsaturated fat
multiple double bonds
cis-unsaturated fat
hydrogens are on the same side of the double bond
trans-unsaturated fats
hydrogens are on opposite sides of the double bond
Are cis- or trans- unsaturated fats more likely to be solid at room temperature?
trans
Are cis fats good or bad?
good
Are trans fats good or bad?
bad
Are saturated fats good or bad?
bad
ampipathatic
hydrophobic + hydrophilic regions
How is cholesterol transported?
lipoproteins
HDL
high-density lipids
What do HDL do?
transports cholesterol to the liver for recycling
LDL
low-density lipids
Is HDL good or bad cholesterol?
good
Is LDL good or bad cholesterol?
bad
Are the heads in phospholipids hydrophobic/hydrophilic?
hydrophilic
Are the tails in phospholipids hydrophobic/hydrophilic?
hydrophobic
How are phospholipids joined?
with a glycerol
What do phospholipids form?
bilayers
What are proteins made from?
amino acids
What are the groups in an amino acid?
1) amino group
2) carboxyl group
3) side chain
4) hydrogen
How many amino acids are there?
20
hydrophobic
does not dissolve in water
polar
tendency to interact with water at biological pH
How can amino acids be classified by R groups?
chemical characteristics of R groups
non-polar R group
hydrophobic amino acid with non-polar side groups
polar R group
neutral - charge is not evenly distributed
acidic R group
negatively charged
basic R group
positively charged
What are the non-polar amino acids?
1) glycine
2) alanine
3) valine
4) leucine
5) isoleucine
6) methionine
7) tryptophan
8) phenylalanine
9) proline
What are the polar amino acids?
1) serine
2) threonine
3) cysteine
4) tyrosine
5) asparagine
6) glutamine
What are the acidic amino acids?
1) aspartic acid
2) glutamic acid
What are the basic amino acids?
1) lysine
2) arginine
3) histidine
human serum albumin
change in direction between 2 helical regions
What can facilitate human serum albumin?
proline residue
P450s
enzyme class that metabolises drugs by utilising oxygen
kinases
enzyme class that phosphorylates substrates to switch them on/off
holoprotein/holoenzyme
complete enzyme with cofactor
apoprotein/apoenzyme
incomplete enzyme without cofactor
protein primary structure
linear sequence of amino acids in a peptide/protein
protein secondary structure
3D form of local segments of proteins
protein tertiary structure
3D shape
protein quaternary structure
number + arrangement of multiple folded protein subunit in a multi-unit complex
How can amino acids be studied?
titrations
How can the primary structure of proteins be studied?
mass spectometry
How can the secondary + tertiary structure of proteins be studied?
x-ray crystallography
How can the quaternary structure of proteins be studied?
synchotron
glycogenesis
glucose to glycogen
synthesis of structural polymers
glucose to extracellular matrix
pentose phosphate pathway
glucose to ribose 5-phosphate
glycolysis
glucose to pyruvate
gluconeogenesis
pyruvate to glucose
anaerobic respiration
pyruvate to lactate
G
free energy
ΔG’°
standard free energy
What does ΔG’° tell us about?
position of equilibium
What does a negative ΔG’° mean?
exothermic
What does a positive ΔG’° mean?
endothermic
ΔG’° +-10kJ/mol
at equilibrium
ΔG’° > +-10kJ/mol
essentially irreversible
What charge does a phosphate have?
negative
Why are phosphate groups added?
1) target for positively-charged enzymes
2) ensures molecule stays within cell
3) redistributes energy
hexokinase
kinase that works on hexos
What is the enzyme classification of hexokinase?
transferase
What is the ΔG’° of glucose to glucose 6-phosphate?
-16.7 kJ/mol
phosphohexose isomerase
same molecule, different arrangement
What is the enzyme classification of phosphohexose isomerase?
isomerase
What is the ΔG’° of glucose 6-phosphate to fructose 6-phosphate?
+1.7 kJ/mol
What is the enzyme classification of phosphofructokinase?
transferase
What is the ΔG’° of fructose 6-phosphate to fructose 1,6-bisphsphate?
-14.2 kJ/mol
galactosemia
defect in one of the enzymes that breaks down galactose
What is glucose required for to produce?
1) energy
2) lactose
3) glycolipids + glycoprotein
4) glycerol for adipose tissue
