Micro - Lecture 7

Front 1

All chemical reactions are determined by two things?

Back 1

Thermodynamics & Kinetics

Front 2

Thermodynamics?

Back 2

Reactions must be energetically favorable.

Front 3

Kinetics?

Back 3

The rate the reaction occurs is determined by activation energy

Front 4

How can both of these be altered? 4 ways

Back 4

By physical change of temperature, pressure, pH, and salinity

Front 5

Catalysis increases the rate of the reaction by ________ the activation energy

The reduction in activation energy will ________ the rate

Back 5

Lowering

Increase

Front 6

Enzymes are proteins, and they ________ chemical reactions by binding to _________.

Back 6

- Catalyze
- Substrate

Front 7

_________ forms the enzyme-substrate complex

Back 7

Enzymes

Front 8

Catalysis occurs in the _______

Back 8

active site

Front 9

An enzyme is a ___ dimensional structure, and in a ______ up form.

Back 9

- 3

-folded

Front 10

All enzymes are ________, but NOT all proteins are_______

Back 10

Proteins

Enzymes

Front 11

Enzymes specifically act on a substrate based on their ______ & _______

Back 11

Structure & Shape

Front 12

Enzymes _______ the reaction rates of their substrates.

May catalyze up to _______ reactions/second

Back 12

- Increase

- 10,000

Front 13

Enzymes are globular proteins, and their 3D structure includes an ______ ______

Back 13

Active Site

Front 14

The site is _______ & ________ shaped so that only the substrate can fit in and react

Back 14

Chemically & Physically

Front 15

Enzyme names end in.....

Back 15

- ASE

Front 16

Nomenclature six major classes

Back 16

1. Oxidoreductase
2. Transferase
3. Hydrolase
4. Lyase
5. Isomerase
6. Ligase

Front 17

Oxidoreductase

Back 17

Redox reactions - add or taking away electrons

Front 18

Transferase

Back 18

move structural components

Front 19

Hydrolase

Back 19

Hydrolytic reactions

Front 20

Lyase

Back 20

Removal of groups without adding water

Front 21

Isomerase

Back 21

rearrangement of a molecule

Front 22

Ligase

Back 22

Attachment of molecules together ( + ATP)

Front 23

Enzymes are proteins, but often require a ________ for functionality.

Back 23

Cofactor

Front 24

The protein alone is called the?

Back 24

Apoenzyme

Front 25

The addition of a cofactor creates a what?

Back 25

Holenzyme

Front 26

Organic cofactors are derivatives of what?

Back 26

Vitamins

Front 27

What are the organic cofactors?

Back 27

- Nicotinamide adenine dinucleotide (NAD+)
- Nicotinamide adenine dinucleotide phosphate (NADP+)
-FMN, FAD, coenzyme A

Front 28

Cofactors can include metal ions such as? (4)

Back 28

Magnesium, manganese, iron, zinc

Front 29

What binds to the enzyme's active site?

Back 29

Substrate

Front 30

After the substrate binds to the enzyme's active site, an enzyme substrate _______ is formed

Back 30

Complex

Front 31

Once the substrate complex is formed it then undergoes what?

Back 31

a transformation

Front 32

True of False...The product of the reaction no longer will fit in the active site, and is then released.

Back 32

True

Front 33

True of False...Once the product of the reaction is released the enzyme can then start "anew"

Back 33

True...Starts over w/ the "Lock and Key" mechanism

Front 34

Enzymes are in the "_____" form when the protein is folded properly and any cofactors are present

Back 34

"Active"

Front 35

True or False....
Activity may be limited by substrate availability.

Back 35

True

Front 36

Factors that influence Enzymes may also have saturation ______

Back 36

Kinetics

Front 37

The proper folding of the ______, binding of cofactors may be affected by physical parameters-temperature, pH

Back 37

- protein

Front 38

For each parameter, there will be an _______

Back 38

- optimum

Front 39

Typically, enzymes within cells have optima at the proper conditions. I.e. Pathogenic (Disease Causing) bacterial enzymes typically work best at ?

Back 39

37C and pH~7

Front 40

Enzymes may be inhibited _________.

Back 40

Chemically

Front 41

Competitive inhibitors bind directly to the ____ ____, and prevent ________ ________

Back 41

- Active Site

- Substrate Binding

Front 42

Non-competitive inhibitors bind elsewhere (________), and prevent ________ of ________

Back 42

(Allosteric)

Front 43

Feedback Inhibition--End product ________ can bind allosterically to _______ _________

Back 43

- Isoleucine

- Threonine deaminase

Front 44

This results in feedback inhibition of the _________ _______.

Back 44

- Conversion reaction

Front 45

Cells have allosteric feedback, to determine levels or _______ and ________ to produce which is needed more or less.

Back 45

- Threonine

- Isoleucine

Front 46

Bacterial Metabolism:
Two types of energy flow

Back 46

- Catabolic & Anabolic

Front 47

Aerobic respiration involves the ________ Cycle, and ETC or (______ _______ ________)

Back 47

- TCA
- Terminal Electron Acceptors

Front 48

Bacterial Metabolism also involves 4 more process which are?

Back 48

- Redox Chemistry
- Fermentation
- Photosynthesis
- Anabolic Pathways

Front 49

What does OIL RIG stand for?

Back 49

Oxidation is lost; Reduction is gained

Front 50

Redox Reactions generate cell energy. The energy cells need in generally stored in _____ ______

Back 50

Chemical Bonds

Front 51

The bonds in a molecule are formed by .......?

Back 51

Electrons

Front 52

_______ are moved between molecules by redox reactions

Back 52

Electrons

Front 53

In biological systems, ______ of the nutrient is coupled w/ reduction of an _______ carrier

Back 53

- oxidation

- Electron

Front 54

The carrier can _______ electrons from the nutrient molecule to other systems, where it is converted to _____

Back 54

- Transfer

- ATP

Front 55

The ________ bonds in ATP contain energy that can be released by _________ breakage

Back 55

- Phosphate

- Enzymatic

Front 56

ATP ---> ADP + Pi releases a great deal of _______. The opposite reaction _______ energy

Back 56

Energy

- Stores

Front 57

Metabolic Pathways for Energy Storage

Back 57

- Glycolysis-Embden Meyerhoff pathway
- Photosynthesis
- Cellular respiration

Front 58

Alternatives to glycolysis in bacteria? 2

Back 58

- Pentose phosphate pathway

- Entner-Duodoroff pathway

Front 59

Metabolic Pathways: Photosynthesis (2)

Back 59

- Conversion of incident light into ATP
- Two pathways-cyclic and non-cyclic

Front 60

Metabolic Pathways: Cellular Respiration (2)

Back 60

- Aerobic Respiration (Krebs cycle)
- Anaerobic respiration - uses a different terminal electron acceptor (Sulfate or Nitrate)

Front 61

Non-Photosynthetic Metabolism:
Respiration is the ____ process
Fermentation is the _______ process.
The Glycolysis pathway to pyruvate is the same in both
- All of these reaction are mediated by ________

Back 61

Respiration: aerobic
Fermentation: anaerobic
- Enzymes

Front 62

Glycolysis - Preparatory Stage 2 stages

Back 62

- Preparatory Stage
- The addition of phosphate groups

Front 63

Preparatory stage is enzymatic processing of ______
The addition of phosphate groups costs the cell _____ in the form of ATP.

Back 63

- Glucose
- Energy

Front 64

Glycolysis - Conversion to Pyruvate: In this step all reactions occur ______

Back 64

Twice

Front 65

Net gain from glycolysis is 2 molecules of ____ and 2 molecules of _______ which can donate electrons in the _____ ________ _______

Back 65

ATP, NADH

electron transport chain

Front 66

Fermentation occurs under what type of condition?

Back 66

Anaerobic

Front 67

Pyruvate is degraded to form organic end products such as ________

Back 67

Ethanol

Front 68

What is the general mechanism that is widespread in bacteria?

Back 68

Fermentation

Front 69

ATP Production via Respiration Two mechanisms?

Back 69

- Substrate level phosphorylation/ dephosphorylation
- Electron Transport Chain

Front 70

ATP Production via Respiration:
Substrate level phosphorylation / dephosphorylation

Back 70

From glycolysis, net 2 ATP
From Krebs cycles, net 2 ATP (goes twice for each glucose)

Front 71

ATP Production via Respiration:
Electron Transport Chain

Back 71

- Electrons from Krebs cycle, glycolysis stored in carriers NADH and FADH2
- ETC results in conversion to ATP via chemiosmotic mechanism

Front 72

Krebs Cycle: To start the cycle, pyruvate is converted to ____

Back 72

Acetyl-CoA

Front 73

Krebs Cycle: Only one ATP is ________ produced.
__ NADH electron carriers, ___FADH2 are produced

Back 73

- Directly
- 4
- 1

Front 74

In terms of carbon atoms, they pyruvate is used up and converted to _____

Back 74

CO2

Front 75

NADH and FADH2 donate electrons to the ETC. The electrons flow down the chain of carriers, they lose energy which the cell captures in the form of ATP molecules. The final product is _____ (uses molecular oxygen)

Back 75

Water

Front 76

Electron Transport Chain Carriers
3 different types of molecules

Back 76

1. Flavoproteins
2. Cytochromes
3. Ubiquinones

Front 77

Flavoproteins

Back 77

Contain flavin as redox coenzyme

Front 78

Cytochromes

Back 78

Use heme group (iron) to shuttle electrons

Front 79

Ubiquinones

Back 79

Only ones that aren't proteins

Front 80

Chemiosmotic Mechanism: Protons cannot cross what?

Back 80

Lipid Bilayer

Front 81

Chemiosmotic Mechanism: By pumping protons (H+) across the membrane, a ______ is set up

Back 81

Gradient

Front 82

Chemiosmotic Mechanism: The proteins in the electron transport chain use the______ in the shuttled electron to pump protons across the _________.

Back 82

- energy
- membrane

Front 83

Chemiosmotic Mechanism:
The electrons flow back into the cell through an _____ ________.

Back 83

ATP synthase

Front 84

# ___ ATP are formed for each electron, Each NADH or FADH2 donates #___ electrons to the process

Back 84

- 3 ATP
- 2 electrons

Front 85

True or False? Bacteria can use alternative terminal electron acceptors when no oxygen is available.

Back 85

True

Front 86

Summary of Cell Carbon Metabolism: Total aerobic respiration yield is # ___ ATP in prokaryotes, and # ____ in eukaryotes

Back 86

- 38 ATP in prokaryotes
- 36 ATP in eukaryotes

Front 87

Cell Carbon Metabolism: The bulk of the ATP is generated through the ____ ____ ___. This is called _______ __________.

Back 87

- Electron Transport Chain
- Oxidative Phosphorylation

Front 88

Photosynthesis: is used by many organisms to generate _____ and _____. I.e. Plants, many types of bacteria

Back 88

- Energy and Carbon

Front 89

Photosynthesis: Two distinct phases ____ & _____ reactions.

Back 89

Light Reactions
Dark Reactions

Front 90

Photosynthesis: Light Reaction called? Dark Reaction?

Back 90

- Photophosphorylation
- Calvin-Benson Cycle

Front 91

Light Reaction - Cyclic reaction?

Back 91

Uses no other inputs besides light energy

Front 92

Light Reactions: Non-cyclic reaction photophosphorylation?

Back 92

Generates oxygen gas, uses water

Front 93

Calvin Benson Cycle: Light-independent or dark reactions. The end result is the production of ______ for use in cell metabolism

Back 93

- Glucose

Front 94

Calvin Benson Cycle: The end result of glucose for cell metabolism is carbon "_____"

Back 94

"Fixation"

Front 95

Calvin Benson Cycle: Cost of CB cycle is # ___ ATP and # __ NADPH

Back 95

- 18 ATP
- 12 NADPH

Front 96

Energy & Carbon Sources: All organisms need _____ & ____ to survive-other things too, but these are the largest components of metabolism

Back 96

- Carbon & Energy

Front 97

Energy & Carbon Sources: Carbon Sources: Autotrophy & Heterotrophy

Back 97

Autotrophy: is fixation of carbon dioxide
Heterotrophy: is use of organic carbon

Front 98

Energy & Carbon Sources: Energy Sources: Phototrophy & Chemotrophy

Back 98

Phototrophy: is energy from light
Chemotrophy: is energy from chemical reactions

Front 99

Anabolism: All of the pathways discussed (except photosynthesis) have been catabolic
Anabolic pathways are utilized to make 5 things?

Back 99

1. Amino Acids
2. Nucleotides
3. Sugars
4. Polysaccharides
5. lipids

Front 100

Anabolism: Some will start with glucose or one of its break down products, others will start with an ______ _______ molecule

Back 100

- Organic nutrient