Module 5 Microbial Metabolism (PPT) Flashcards
1
Q
bacterial products examples (commercially or medically important)
A
i.e. Lactococcus and Lactobacillus, Streptococcus mutans
2
Q
microorganisms that are important in laboratory (identification of microorganisms) (3)
A
(i.e. E. coli, Klebsiella, and Enterobacter)
3
Q
- oxidative ; exergonic (releases energy); breaking down
- reductive ; endergonic; building up
A
- Catabolism
- Anabolism
4
Q
Energy Source: Sunlight
Carbon Source: Carbon dioxide
A
Photoautotroph
5
Q
Energy Source: Sunlight
Carbon Source: Organic compounds
A
Photoheterotroph
6
Q
Energy Source: Inorganic chemicals
Carbon Source: Carbon dioxide
Nitrogen Source: Inorganic
A
Chemolithoautotroph
7
Q
Energy Source: Organic compounds
Carbon Source: Organic compounds
Nitrogen Source: Organic or Inorganic
A
Chemoorganoheterotroph
8
Q
Energy Source: Sunlight
Carbon Source: Carbon dioxide
Nitrogen Source: Inorganic
Hydrogen Source: H2S or H2
A
Bacteria
9
Q
Energy Source: Sunlight
Carbon Source: Carbon dioxide
Nitrogen Source: Inorganic
Hydrogen Source: Photolysis of H20
A
Cyanobacteria
10
Q
Energy Source: Sunlight
Carbon Source: Carbon dioxide
Nitrogen Source: Inorganic
Hydrogen Source: Organic compounds
A
Photoorganotrophic Bacteria
11
Q
- “sugar splitting”
- occurs in cytosol of bacteria
- converts glucose (6-C) to pyruvate (3-C)
- can occur in the absence of oxygen
- enzyme-mediated
A
Glycolysis
12
Q
Glycolysis order (11)
A
- Glucose
- Glucose 6-phosphate
- Fructose 6-phosphate
- Fructose 1,6-bisphosphate
- (optional) Dihydroxyacetone phosphate
- Glyceraldehyde 3-phosphate
- 1,3-Bisphosphate glycerate
- 3-Phosphoglycerate
- 2-Phosphoglycerate
- Phosphoenolpyruvate
- pyruvate
13
Q
10 enzymes in glycosis
A
- Hexokinase
- Phosphoglucoisomerase
- Phosphofructokinase
- Aldolase
- Triose Phosphate isomerase
- Glyceraldehyde phosphate dehydrogenase
- Phosphoglycerokinase
- Phosphoglyceromutase
- Enolase
- Pyruvate kinase
14
Q
Glycolysis gross energy yield and net energy yield
A
- gross energy yield = 4 ATP + 2 NADH
- net energy yield = 2 ATP + 2 NADH
15
Q
- phosphogluconate pathway or hexose monophosphate shunt
- other metabolic pathway used by cells to break down glucose
A
Pentose Phosphate Pathway
16
Q
- generates NADPH, ribose 5-phosphate, and erythrose 4-phosphate
(intermediates)
A
Pentose Phosphate Pathway
17
Q
Pentose Phosphate Pathway (6)
A
- Glucose
- Glucose 6-P
- 6-Phosphogluconate
- Ribulose 5-P
- Ribose 5-P -> nucleotide synthesis (opt)
- Erythrose 4-P / Xylulose 5-P / Sedoheptulose 7-P
- Fructose 6-P / Glyceraldehyde 3-P
18
Q
aerobic (O2-requiring) breakdown of nutrients with accompanying synthesis
of ATP
A
Aerobic Respiration
19
Q
Aerobic Respiration comprises three stages in the metabolic breakdown of glucose
A
❑ transition step/conversion of pyruvate to acetyl CoA
❑ Krebs cycle / citric acid cycle
❑ oxidative phosphorylation: electron transport chain and chemiosmosis
20
Q
Aerobic Respiration takes place in the
A
cytoplasm
21
Q
- pyruvate converted to acetyl coenzyme A
A
Transition Step
22
Q
Transition Step
- removal of carboxyl group from pyruvate and given off as ________
- 2-C compound is oxidized, ______ is reduced to _______
- _________ joins the 2-C compound forming acetyl-coenzyme A (acetyl CoA)
A
- CO2
- NAD+ -> NADH
*coenzyme A
23
Q
Transition Step energy yield (per glucose):
A
2 NADH
24
Q
- named after Hans Krebs
- also known as citric acid cycle or tricarboxylic acid cycle
- yields more energy than glycolysis
A
Krebs Cycle
25
Krebs Cycle (8)
1. Acetyl-CoA (release CoA) + Oxaloacetae
2. Citrate
3. Isocitrate: (NADH, H+, CO2)
4. α-ketoglurate: (ATP, NADH, H+ , CO2)
5. succinyl CoA
6. succinate: (FADH2)
7. fumarate
8. Malate: (NADH, H+)
26
Krebs Cycle energy yield (per glucose)
2 ATP + 6 NADH + 2 FADH2
27
* final stage of cellular respiration
* “big energy payoff” stage
* uses electron transport chain and chemiosmosis
* located in the cell membrane
Oxidative Phosphorylation
28
membrane-embedded electron carriers that pass electrons sequentially from one to another
electron transport chain
29
movement of ions (H+) down their electrochemical gradient that generates ATP
chemiosmosis
30
Electron carriers (4)
* I – flavoprotein (flavin monunucleotide)
* II – Fe-S protein
* Quinone (Q)- non-protein mobile carrier ; aka CoQ
* Cytochrome (C) – mobile carrier; Q to oxygen
31
– enzyme that makes ATP from ADP and inorganic phosphate
- uses energy of ion gradient top power ATP synthesis
ATP synthase
32
Prokaryotes have varied types and arrangement of electron transport chain components which could provide a mechanism to distinguish certain types of
bacteria for example
cytochrome production of Pseudomonas and Campylobacter
33
Detects the presence of an enzyme “oxidase” produced by certain bacteria which will reduce the dye – tetramethyl-p-phenylene diamine dihydrochloride.
is used to identify bacteria that produce cytochrome c oxidase, an enzyme of the bacterial electron transport chain
Positive test is indicated by the development of a purple colour.
OXIDASE TEST
34
Oxidase positive (3) PURPLE COLOR
Pseudomonas, Vibrio, Neisseria
35
Oxidase negative (2)
– Salmonella, Shigella
36
Energy Conversion
* 1 NADH
* 1 FADH2
* 1 NADH = 3 ATP
* 1 FADH2 = 2 ATP
37
* oxygen is not the final electron acceptor in the electron transport chain
* anaerobic or facultative bacteria
* less amount of energy is released in the reduction of inorganic chemicals
other than molecular oxygen
Anaerobic Respiration
38
t or f
aerobic respiration less efficient form of energy transformation than anaerobic Respiration
F
Anaerobic Respiration is less efficient form of energy transformation than aerobic respiration
39
Anaerobic Respiration examples
- Nitrate reduction E.coli (FAD, FeS, Q, cyt b, Mo) ETC
- sulfate reduction
- carbon dioxide reduction
40
Nitrate reduction ex
E.coli (FAD, FeS, Q, cyt b, Mo) ETC
41
sulfate reduction ex
(i.e. Desulfovibro)
42
carbon dioxide reduction ex
(i.e. Methanobacterium and Methanococcus)
43
* makes a few ATP molecules
* Krebs cycle and oxidative phosphorylation are shut down
* organic molecule accepts the electrons (not O2)
Fermentation
44
Fermentation example
E. coli (use any of the three ATP generating options), LAB (obligate fermenters), obligate anaerobes
45
Fermentation
- Lactic acid
- Ethanol
- Lactic acid : animals
- Ethanol: Yeast
46
Terminal Electron Acceptor of:
-lactic acid
-ethanol
-2,3-butanediol
- pyruvate
- acetaldehyde
- acetoin
47
lactic acid fermentation products
Cheese, yogurt, pickles, cured sausages
Causes tooth decay, spoilage of some food
48
Ethanol and CO2 fermentation products
wine, beer, spirits, bread
(Saccharomyces cerevisiae and Zymomonas)
49
Example of Products/Importance
- Butyric acid fermentation
- Propionic acid fermentation
Clostridium
Swiss cheese (Propionibacterium)
50
Lactic acid, succinic acid, ethanol, acetic acid, carbon dioxide, gases fermentation
Differentiate members of Enterobacteriaceae
Mixed Acids fermentation
51
IMViC test / MR/VP test
- used to identify bacterial species, especially coliforms
methyl red test:
- (+) red: E.coli
- (-) yellow/orange: Klebsiella
Voges-Proskauer test
- (+) pink: Klebsiella
- (-) no pink: E.coli
52
streptococcus, lactobacillus, bacillus end products of fermentation
lactic acid
53
Saccharomyces fermentation product
ethanol and co2
54
propionibacterium fermentation product
propionic acid, acetic acid, CO2, and H2
55
Clostridium fermentation product
Butyric acid, butanol, acetone, isopropyl alcohol, and CO2
56
Escherichia and Salmonella fermentation product
Ethanol, lactic acid, succinic acid, acetic acid, CO2 and H2
57
Enterobacter fermentation product
Ethanol, lactic acid, formic acid, butanediol, acetoin, CO2, and H2
58
process by which light energy is converted to chemical energy
photosynthesis
59
photosynthesis takes place in
cell membrane
60
* contains chlorophyll or chlorophyll-like pigments
* thylakoid membranes (cyanobacteria)
* chlorosomes (green bacteria)
* extensive cell membrane invaginations (purple bacteria)
FOR PHOTOSYNTHESIS
cell membrane
61
intermediary product and major end product of photosynthesis
ATP (intermediary product) and glucose (major end-product)
62
prokaryotes that undergoes photosynthesis
green sulfur bacteria, purple sulfur bacteria, cyanobacteria
63
prokaryotes that undergoes photosynthesis
diatoms, dinoflagellates, algae
64
T OR F
photosynthesis occurs in the same manner as eukaryotic microorganisms and green plants
T
65
Mg-containing green pigment that absorbs light energy
chlorophyll a
66
light-receiving systems
photosystems I and II
67
chlorophylls of purple and green photosynthetic bacteria
bacteriochlorophylls
68
accessory pigments of photosynthetic prokaryotes and eukaryotes
carotenoids
69
accessory pigments of cyanobacteria
and red algae
phycobilins
70
can be found on photosystems (3)
* chlorophylls and accessory pigments
* reaction center pigments
* antennae pigments –
71
electron donors in photosynthetic process
reaction center pigments
72
– “funnel”, make up antenna complex
antennae pigments
73
* photophosphorylation – light is involved in ATP formation
* energy-fixing reactions
* oxygenic – produces oxygen in photosynthesis
light-dependent reaction
74
reaction center of the two photosystems
II - P680
I - P700
75
The three products of the light reaction of photosynthesis are
ATP, NADPH, and O2
76
Phases of Light independent reaction (Calvin Cycle) (3)
1. Carbon Fixation
2. Reduction
3. Regeneration of the CO2 acceptor
77
catalyzes a reaction between CO2 and RuBP, which forms a six-carbon compound that is immediately converted into two three-carbon compounds.
RuBisCo
78
CO2 acceptor in calvin cycle
RuBP (Ribulose bisphosphate)
79
a sugar output in calvin cycle
G3P (Glyceraldehyde-2-phosphate)
80
* bacteriochlorophylls – chlorophyll-like pigments
* do not use water as source of hydrogen ions
* fatty acids and other organic or inorganic substances are used as source of H+ ions
* no oxygen is liberated
* anoxygenic
WHAT PROKARYOTE?
green sulfur bacteria and purple sulfur bacteria
81
bacteriorhodopsin pigment
archaea (extreme halophiles)
82
Oxygenic photosynthesis and
pigments (chlorophyll a) as in algae
and plants produces
formaldehyde (CH2O)
83
T OR F
All other photosynthetic bacteria (e.g. green sulfurbacteria) have bacterial chlorophyll and anoxic photosynthesis
T
84
primary light harvesting pigment (oxygenic and anoxygenic)
chlorophyll a - oxygenic
bacteriochlorophylls - anoxygenic
85
phycobilins can be found on
cyanobacteria
