Microbial Metabolism Flashcards
(127 cards)
1
Q
What is the purpose of enzymes?
A
to direct and speed up the rate of chemical reactions
2
Q
When writing a chemical reaction this is always written above the arrow
A
Enzymes
3
Q
3 pathways that make up aerobic respiration
A
Glycolysis
Transition Reaction
Krebs Cycle
4
Q
What is the terminal electron acceptor in Aerobic respiration?
A
Oxygen
5
Q
In anaerobic respiration the terminal electron acceptor is
A
something other than Oxygen & produced bad smells
6
Q
Energy yield from EMP pathway
A
2 ATP, 1 NADH
= 2 Substrate ATP, 3 Oxidative ATP, 5 total ATP
7
Q
Energy yield from Transition pathway
A
1 NADH
= 3 oxidative ATP
8
Q
Energy Yield from Kreb’s Cycle
A
1 ATP, 3 NADH, 1 FADH2
= 1 Substrate, 11 Oxidative
9
Q
Total of all chemical reactions occurring within a cell
A
Metabolism
10
Q
Breaking the bonds of molecules to form smaller molecules
A
Catabolism
11
Q
Releases energy from molecules transforming it to ATP - energy conserving process
A
Catabolism
12
Q
A process that uses smaller molecules to form macromolecules
A
Anabolism
13
Q
Energy is used during this reaction
A
Anabolic reaction
14
Q
ATP is made up of
A
ADP and one other phosphate group
15
Q
Three parts of ATP molecule
A
Nitrogenous base - Adenine
5 Carbon Sugar - Ribose
3 Phosphate Groups - phosphorus surrounded by oxygen and hydrogen.
16
Q
When a cell needs energy it breaks the terminal Phosphate group from _________ forming __________
A
Adenosine Triphosphate (ATP); Adenosine Diphosphate
17
Q
Biological catalysts that increase the rate of chemical reactions
A
Enzymes
18
Q
Resistance to a reaction; this is lowered by Enzymes
A
Energy of Activation
19
Q
Enzymes are not altered or consumed so can be used multiple times
A
True
20
Q
Active site
A
Specific site on an enzyme that binds to substrate
21
Q
Names of enzymes usually end in -_______
A
-ase
22
Q
Protein Structures are made up of
A
Primary structure, secondary structure, and tertiary structure and MAY have a quaternary structure
23
Q
Six different categories of enzymes
A
- Hydrolase
- Isomerase
- Ligase (or Polymerase)
- Lyase
- Oxidoreductase
- Transferase
24
Q
Hydrolase
A
Catabolic enzyme. Uses water - brings in water & uses it to help break apart a larger molecule
25
Isomerase
Neither catabolic or anabolic. Rearranges the atoms of a single molecule
26
Ligase or Polymerase
Anabolic enzyme. Joins two or more chemicals together
27
Lyase
Catabolic enzyme. Splits a chemical into smaller parts without using water
28
Oxidoreductase
Transfer of electrons or hydrogen atoms from one molecule to another
29
Transferase
May be anabolic. Moving a functional group from one molecule to another.
30
A- + B --> A + B-
Oxidoreductases
31
A - B + C --> A + B - C
Transferases
32
A - B + H2O --> A - H + B - OH
Hydrolases
33
X Y
| A - B --> A = B + X - Y
Lyases
34
X Y Y X
| A - B --> A - B
Isomerases
35
A + B --> A - B
Ligases
36
Enzymes can be simple or _______
Holoenzymes
37
Enzymes that contain both a protein portion (Apoenzyme) and a nonprotein portion (cofactor)
Holoenzymes
38
Enzymes that consist of protein alone
simple enzymes
39
Enzymes that are transported to the outside of the cell where they can have their function
Exoenzymes
40
Enzymes that are produced and retained inside the cell
Endoenzymes
41
Enzymes that are always present in an active form
Constitutive enzymes
42
Enzymes that are either not always present or have to be turned on
Regulated enzymes
43
Two main types of cellular reactions
Synthese or condensation reactions
AND
Hydrolysis Reactions or degradation reactions
44
Catabolic reaction that requires the input of water to break down substrates into smaller molecules
Hydrolysis reaction
45
Anabolic reactions that requires ATP to form covalent bonds between smaller substrate molecules. Releases one water molecule for each bond formed
Synthesis (or Condensation) reactions
46
As conditions get further away from optimum temperature and pH ranges for enzymes
Enzymes activity slows down and denaturation of the enzymes occurs
47
can be in the form of drugs or toxins. Mimic the substrate and compete for the active site of particular enzymes
Competitive Inhibitor
48
Allosteric Regulators
effector molecules that binds to the allosteric site on an enzyme and changes the shape of the active site; and be allosteric inhibition or allosteric activation
49
Transfer of electrons from one molecule to the other
Oxidation/Reduction (Redox) reactions
50
Oxidation
Loss of electrons (hydrogens)
51
Reduction
Gain of electrons (hydrogens)
52
Sample Redox Reaction - what is happening, what was oxidized, what was reduced?
C6H12O6 + 6O2 --> 6CO2 + H2O + Energy
Aerobic Respiration
Glucose is oxidized--> Carbon Dioxide
Oxygen is reduced --> water
53
Two electron carriers involved in catabolic pathways (oxidized & reduced forms)
Reduced : NADH & FADH2
Oxidized: NAD+ & FAD or FADH
54
Electron carrier for parabolic pathways
Reduced: NADPH
Oxidized: NAD+
55
2 mechanisms of ATP formation
Substrate-level Phosphorylation
Oxidative Phosphorylation
56
Draw the flowchart of Aerobic Respiration
Draw
57
Krebs Cycle Primary Reaction
Acetyl-CoA (2C) + Oxaloacetate (4C) --> Citrate (6C)
58
From one molecule of glucose
Glycolysis (EMP): 2 ATP 2 NADH
Transition Rxn: 2 NADH
Kreb's Cycle: 2 ATP 6 NADH 2 FADH
Total = 4 ATP 10 NADH 2 FADH
= 4 SUBTRATE ATP, 34 OXIDATIVE ATP, 38 TOTAL
59
High energy electrons are shuttles through a chain of electron carriers until they are lower energy to its terminal electron acceptor
Electron Transport Chain
60
In Eukaryotes the ETC takes place in____________
The inner membrane of the mitochondria
61
In Prokaryotes the ETC takes place in the ____________
Plasma Membrane
62
Energy released from electron transfer is used by _________ to produce _________ through ____________.
ATP Synthase; ATP; Oxidative Phosphorylation
63
In Chemiosmosis hydrogen ions (protons) are driven to the endoplasmic space creating an
Electro-chemical gradient
64
In ETC as higher number of protons are moved across membrane the outside becomes more
Acidic and positively charged
65
Drives the hydrogen ions through ATP synthase (oxidative phosphorylative event)
Proton Motive Force
66
Most common terminal electron acceptor in Anaerobic respiration
Nitrate, Sulfate, Carbonate
67
Falcultative Anaerobes
Are anaerobic when oxygen is not available
68
Obligate Anaerobes
Only carry out anaerobic respiration. Do not have aerobic respiration transport system because oxygen is toxic to them
69
Incomplete oxidation of glucose molecule in the absence of oxygen
Fermentation
70
Common byproducts of Fermentation
Ethanol, butanol, lactate, formate
71
Yields only small amounts of ATP therefore unicellular organisms may be able to rely on this but multicellular organisms this happens nut only for short amounts of time
Fermentation
72
Themes of Fermentation
Electron acceptor is usually pyruvate or a pyruvate derivative
NADH becomes oxidized and is used back during Glycolysis
Oxidative Phosphorylation (ATP Synthase) does not operate so only substrate ATP is produced (much less)
73
Main thing to know about Fermentation
Pyruvate is electron acceptor. NADH formed in Glycolysis donates electron to pyruvate and NAD returns to pathway. SUBSTRATE ATP will continue to be produced.
74
The byproducts of Fermentation depend on
The enzymes possessed by the microbes and therefore the fermenration pathways that will follow
75
Types of fermentation
Alcoholic Fermentation
Acidic Fermentation
Mixed Acid Fermentation
76
Production of ethanol & carbon dioxide
- predominantly done by yeasts
- for beverages and breads
Alcoholic Fermentation
77
Production of lactate
| - produced yogurt, sauerkraut, cheese
Acidic Fermentation
78
Production of multiple byproducts through multiple Fermentation pathways
Mixed Acid Fermentation
79
Role of Lipase
Cuts fatty acid chains from glycerol molecules
80
Each turn of the Fatty Acid Cylce generates:
1 Acetyl CoA
1 NADH
1 FADH2
81
1 turn of the Krebs Cycle generates
1 ATP
3 NADH
1 FADH2
82
Proteases
Enzymes secreted outside the cell to break down protein molecules into individual amino acids
83
Deamination
After protein molecules are broken down into individual amino acids. AAs are brought into cell and amine group (nitrogen group) is removed.
84
What pathway is the following intermediate found?
Ribose 5 Phosphate
Pentose-phosphate pathway
85
2-keto-3-deoxy-6-phosphogluconate
Entner-deudoroff pathway
86
Acetyl CoA
Krebs Cycle
87
Erythrose-4-phosphate
Pentose-phosphate pathway
88
During _______ NADPH donates an electron to the anabolic reaction
biosynthesis
89
If a molecule gains electrons it has been
reduced
90
If a molecule loses electrons it has been
oxidized
91
Beta Oxidation
Lipid Catabolism - triglyceride is broken down and enters the fatty acid cycle
92
If 18 hydrocarbon fatty acid was catabolized how many NADH would be produced from the fatty acid cycle?
9
93
Amphibolic
bi-directional pathways
94
Reverse of EMP pathway
Gluconeogenesis
95
Anabolic reactions require and energy source
coupled to ATP
96
Biosynthetic pathways require and electron source, that is
NADPH
97
many enzymes that are used in catabolism are also used in anabolism meaning they are
Amphibolic
98
An allosteric inhibitor bind to the_____ and does what?
allosteric site; alters the shape of the active site
99
How much NADH is produced in the EMP pathway?
2 NADH
100
How much substrate ATP is produced in the EMP pathway?
2 ATP
101
What is the net yield ATP produced from one molecule of Glucose?
38 ATP
102
Initial substrate of Entner-Doudoroff Pathway
Glucose
103
Final Products of Entner Doudoroff Pathway
Pyruvate (goes to transition rxn or fermentation) & G3P (goes to second half of glycolysis)
104
Initial substrate of Transition reaction
Pyruvate
105
Final product of Transition reaction
Acetyl CoA
Also produced 1 NADH & 1 CO2 is released
106
For each Acetyl CoA oxidized the Krebs cycle generates
3 NADH
1 FADH2
1 ATP
107
Intermediates of EMP Pathway in order
Glucose --> Glucose-6-Phosphate --> Fructose-6-Phosphate --> Fructose-1,6-diphosphate --> 1 G3P & 1 DHAP (converts to 2nd G3P) --> 2 Pyruvates
108
DHAP is converted to G3P through the
Fatty Acid Cycle
109
organic compounds are the final electron acceptors
In fermentation
110
Serves as the electron acceptor in fermentation
Pyruvate or pyruvate derivative
111
3 pathway options for Glycolysis
Embden-Meyhoff-Parnas Pathway
Entner-Doudoroff Pathway
Pentose Phosphate Cycle
112
Pyruvate is oxidized to Acetyl CoA in the
Transition Reaction
113
Acetyl-CoA is Oxidized in the
Krebs Cycle
114
Generates ATP through oxidative phosphorylation
Electron Transport Chain
115
Net Yield of the Entner-Doudoroff Pathway
2 pyruvates
1 ATP
1 NADH
1 NADPH
116
Intermediates of the Entner-Doudoroff Pathway
```
Glucose -->
Glucose 6-phosphate -->
6-phosphogluconate -->
2-keto-3-deoxy-6-phosphogluconate -->
Pyruvate & G3P
```
117
Metabolites of Pentose Phosphate Pathway - used in biosynthesis
NADPH
Ribose-5-phosphate
Erythrose-4-Phosphate
118
Intermediates of Pentose Phosphate Pathway - feed to the EMP pathway
Glyceraldehyde 3-Phosphate
Fructose-6-Phosphate
Glucose-6-Phosphate
119
Proteases are used in
Protein catabolism (deamination process)
120
During fermentation NADH donates an electron to the electron transport chain (T/F)
False-
| During fermentation NADH donates an electron to pyruvate
121
Amino acids that are chemically bonded together to form a protein would be completed by a
Ligase
122
The steps of anaerobic Electron Transport chain in order:
1. NADH is oxidized
2. Ubiquinone & cytochromes transfer an electron
3. Protons are pumped to the periplasmic space
4. Sulfate is reduced to H2S
123
Characteristics of anabolic reactions
- Endergonic
- Include dehydration reactions
- involve the production of cell membrane constituents
124
Characteristics of catbolic reactions
- breaks large molecules into smaller ones
- exergonic
- Includes hydrolytic reactions
125
Coenzymes are
Organic cofactors
126
Ribozymes process
RNA molecules on eukaryotes
127
The fermentation of one glucose molecule by a bacterium allows a net gain of how many ATP molecules?
2 ATP
