Biosci 106

Front 1

Hydrophobic

Back 1

non-polar.

found inside protein molecule.

Front 2

Hydrophillic

Back 2

polar.

found outside protein molecule.

Front 3

Glycine

Back 3

small...fits into small spaces.

flexible.

not chiral!

Front 4

Cysteine

Back 4

can form cross-links.

Front 5

Proline

Back 5

is kinky.

introduces kinks and rigidity.

Front 6

a- helix

Back 6

stiff, strong,

H-bonding + disulfide bonds

coils in right-hand direction.

Front 7

B- sheets

Back 7

soft, flexible

H-bonding + disulfide bonds

parallel/anti-parallel

Front 8

proline

Back 8

disrupts helices = no H bonds

Front 9

Uses for GFP

Back 9

pigs- proved concept

zebra fish- pollution, heart contracting

rats- cancer, blood vessels of tumour glow

Front 10

Domain structure

Back 10

efficient folding

clefts created between domains

dif. functions

flexibility

Front 11

Antibody antigen binding site formed by

Back 11

6 hypervariable loops

Front 12

Recognise antigens by

Back 12

shape

size

charge

polar/non-polar

Front 13

Influenza virus enters by

Back 13

endocytosis.

Front 14

Influenze virus exits via

Back 14

budding.

Front 15

Surface proteins of influenze virus

Back 15

- Haemagglutin- binds to sialic acid in host. gives entry into cells

- Neuraminidase- removes sialic acid, stops new virus particles sticking together.

Front 16

Target of influenza drugs

Back 16

block active site of neuraminidase.

Front 17

Assumptions of Michaelis-menten model

Back 17

catalysis is slowest step

more substrate than enzyme

conc. of enzyme/substrate is constant

reverse rxn is negligible.

Front 18

Steady state assumption

Back 18

rate of formation of ES is equal to its breakdown.

Front 19

apo enzymes

Back 19

protein + associated non-protein component.

Front 20

holo enzymes

Back 20

completely protein, fully active.

Front 21

Competitive inhibition

Back 21

inhibitor competes for active site.

rate catalysis decreases

overcome by increasing substrate conc.

Front 22

Non competitive inhibition

Back 22

inhibitor can bind simultaneously with substrate

binds at another active site.

reduces catalysis (less efficient)

Front 23

Uncompetitive inhibition

Back 23

binds to enzyme-substrate complex.

can't be overcome by increasing substrate conc.

Front 24

Vmax

Back 24

maximum velocity of an enzyme-substrate catalysed rxn.

Front 25

Km

Back 25

enzymes attraction to substrate... high Km= low affinity (not very attracted)

Front 26

X and Y axis of enzyme vs substrate

Back 26

Y= 1/v

X= 1[s]

Front 27

Lineweaver-burk plot Y and X intercepts

Back 27

Y intercept= 1/vmax

X intercept= 1/-Km

Front 28

Homotropic effect

Back 28

binding of substrate to one active site influences binding of substrate to another active site.

Front 29

Allostery

Back 29

more than one active site.

Front 30

Heterotropic effect

Back 30

effectors either inhibit or activate.

Front 31

Other part of enzyme (not active site) is for...

Back 31

correct spatial orientation

micro-environment

recognition + control.

Front 32

Co-factors

Back 32

other compounds necessary for enzyme to function.

Front 33

Prosthetic groups

Back 33

co-factors tightly bound to enzyme (don't let go)

Front 34

Saturated

Back 34

only contains single bonds.

Front 35

Unsaturated

Back 35

double bonds, lower melting point.

Front 36

Hydrogenation

Back 36

increase fats melting point (spreadable)

add H's to polyunsat vege oils

creates trans fats!

Front 37

Free fatty acids

Back 37

from breakdown of fats (triglycerides)

not water soluble- transported by serum albumin.

Front 38

Essential fatty acids

Back 38

mammals can't introduce DB beyond C9.

diet= linoleic acid (seeds, nuts)

precursor of other lipids.

Front 39

Roles of fatty acids

Back 39

building blocks of phospholipids

modify proteins (covalent attachment)

fuel molecules

derivatives= hormone/intercellular messengers

Front 40

Phospholipids

Back 40

platform= glycerol, 3C alcohol or sphingosine

disease where accumulates= Niemann pick.

Front 41

Glycolipids

Back 41

asymmetrical orientation.

sugar group on outside

Front 42

Cholesterol

Back 42

nearly all animal cell membranes.

steriod backbone.

OH group.

Front 43

Fatty acid degradtion occurs in the...

Back 43

mitochondrial matrix

Front 44

Fatty acid synthesis occurs in the...

Back 44

cytosol.

Front 45

3 stages of FA degradation

Back 45

1. Lipolysis

2. Activation

3. Broken down...acteyl coA...CAC cycle.

Front 46

What molecule carries activated FA into mitochondrial matrix?

Back 46

carnitine.

Front 47

Antiport

Back 47

transport simultaneously in opposite directions.

Front 48

Ketone bodies

Back 48

major fuel source eg. heart, kidneys.

water soluble/ transportable acetyl CoA.

Front 49

Entry of acetyl CoA in CAC depends on...

Back 49

oxaloacetate.

Front 50

Times of low OA (oxaloacetate)

Back 50

1. Fasting

2. Insulin-dependent diabetes.

Front 51

Priorities of metabolism in starvation

Back 51

1. provide glucose to dependent tissues eg. brain, RBC.

2. preserve protein

Front 52

Fatty acid synthesis

Back 52

acetyl CoA ---> malonyl CoA

irreversible rxn, catalysed by acetyl CoA carboxylase.

Ends with C16-acyl ACP.

Front 53

Acetyl CoA carried across inner mitochondrial membrane by...

Back 53

citrate.

Front 54

FA synthesis optimum conditions

Back 54

lots of carbohydrate

not a lot of FA

Front 55

Global regulation of ACC

Back 55

Glucagon + epinephrine- inhibit ACC, stimulate phosphorylation.

Insulin stimulates, removes phosphate.

Front 56

Local regulation of ACC

Back 56

allosteric stimulation by citrate

allosteric stimulation by palmitoyl CoA.

Front 57

FAS (fatty acid synthase)

Back 57

inhibitors= useful drugs eg. cancer (decrease signalling)

increase immune system (interleukin makes memory T cells store fat)

Front 58

Cholesterol

Back 58

Creates membrane fluidity

Precursor for signal molecules eg. hormones + vitamin D.

Front 59

3 steps to cholesterol synthesis

Back 59

1. synthesis of isopentenyl pyrophosphate.

2. condensation of 6 isopentenyl p. to squalene.

3. cyclization of squalene to tetracyclic product to cholesterol.

Front 60

Initial step of cholesterol synthesis catalyzed by...

Back 60

HMG- CoA reductase.

Front 61

Control of HMG- CoA reductase

Back 61

1. rate of reductase mRNA synthesis

2. rate of reductase mRNA translation

3. degradtion of reductase

4. phosphorylation of reductase

Front 62

LDL

Back 62

low density,

bad cholesterol

B100

cholesterol transport

Front 63

HDL

Back 63

high density,

A

good cholesterol

reverse cholesterol transport (excreted by liver)

Front 64

Cholesterol transported by...

Back 64

lipoproteins.

Front 65

Familial hypercholesterolaemia (FH)

Back 65

failure to release LDL + loss of receptor.

Front 66

Site of LDL binding

Back 66

LA domain