Microbial Metabolism Flashcards
(134 cards)
1
Q
what are the 4 processes that form cellular metabolism?
A
Enzyme mediated Catalysis, reaction coupling, energy harvesting by redox reactions, use of membranes to form gradients of charge and chemical concentration
2
Q
What ion is included in fueling
A
PO4 3-
3
Q
What type of energy is used in fueling products
A
ATP, PMF
4
Q
What 2 ions are used in biosynthesis after fueling products?
A
SO4 2-, and NH3
5
Q
what macromolecules make lipids and lipopolysaccharide?
A
Fatty acids
6
Q
What building block makes lipolysaccharide, glycogen, and murein?
A
sugars
7
Q
what building block makes murein and protein?
A
amino acids
8
Q
What building block makes RNA and DNA?
A
nucleotides
9
Q
What structure does glycogen contribute to?
A
Inclusions
10
Q
What macromolecules contribute to the cell envelope?
A
Lipid, lipopolysaccharide, murein, and protein
11
Q
what macromolecule is the pili assembled from
A
protein
12
Q
what macromolecules contribute to building cytosol?
A
protein and RNA
13
Q
What macromolecules contribute to building ribosomes?
A
Protein and RNA
14
Q
What macromolecules contribute to building the nucleoid?
A
Protein and DNA
15
Q
What is active transport?
A
How cells accumulate solutes AGAINST the concentration gradient
16
Q
What are the 3 classes of transporters?
A
simple transport
group translocation
ABC system
17
Q
What energy source dives simple transport?
A
Proton Motive Force
18
Q
What energy source drives group translocation?
A
phosphoenolpyruvate
19
Q
What energy source drives ABC transporters?
A
ATP
20
Q
What is a symport?
A
H+ and solute are transported in one direction
21
Q
What is an antiport?
A
H+ and solute are transported in opposite direction
22
Q
What is an example of a symport?
A
E.Coli lac permease
23
Q
What is an example of an antiport?
A
sodium proton antiporter
24
Q
What happens to a substance that is transported by group translocation?
A
it is chemically modified
25
what is an example of a group translocation system/
Phosphotransferase system in E.Coli
26
What macromolecules does phosphotransferase use?
glucose, fructose, and mannose
27
How many proteins are required for phosphotransferase?
5
28
Where does the phosphoenolpyruvate energy used in phosphotransferase come from?
glycolysis
29
What type of affinity does ABC systems have to substrates?
HIGH
30
what proteins are required for Gram negatives in ABC systems
transmembrane, ATP hydrolyzing, adn periplasmic binding protein
31
What proteins are required for gram positives in ABC systems?
transmembrane, ATP hydrolyzing, and substrate binding on external surface of cytoplasmic membrane
32
Define Metabolism
the sum of all chemical reactions that occur in a cell
33
Define catabolism
energy releasing metabolic reactions
34
Where do chemoorganotrophs get their energy?
from organic chemicals
35
Where do chemolithotrophs get their energy?
Oxidizing inorganic compounds
36
Where do Phototrophs get their energy>
convert light to ATP
37
Where do heterotrophs get their energy
Obtaining carbon from organic substances
38
Where do autotrophs get their energy
obtaining carbon from CO2
39
What is the reducing power in fueling products?
NADH
40
What do fueling reactions supply?
Energy, Reducing power, and 13 precursor metabolites
41
What does the entry process do?
Move organic and inorganic food substrates from enviornment into the cell
42
What does the Feeder pathway do>
convert intracellular food substrates into a metabolite of central metabolism
43
what is central metabolism?
a group of pathways which produce all the precursor metabolites
44
What is the simplest way to generate ATP?
Substrate level phosphorylation
45
What is the first step of substrate level phosphorylation?
A organic substrate becomes phosphorylated
46
What is the second step of substrate level phosphorylation?
The phosphorylated substrate is oxidized and energy is trapped
47
What cycles is substrate level phosphorylation pertinent to?
glycolytic pathway and TCA cycle
48
What is the equation for lactic acid fermentation?
Pyruvate + NADH----> lactic acid + NAD+
49
where is lactic acid fermentation found?
bacteria, some protozoa, human skeletal muscle
50
what are the bacteria that produce only lactic acid?
homolactic fermenters
51
What are the bacteria that produce other products beside lactic acid such as ethanol, CO2?
heterolactic fermenters
52
How many steps is alcoholic fermentation?
2
53
what are the 2 equations of alcoholic fermentation?
pyruvate-> acetaldehyde +CO2
acetaldehyde +NADH-> ethanol +NAD+
54
where is alcoholic fermentation found?
fungi and yeasts mainly, but some bacteria
55
what are the equations for formic acid and mixed acid fermentation?
pyruvate+CoA-> acetyl CoA + formic acid
HCOOH -> CO2 +H2
56
Why is formic acid and mixed acid fermentations useful?
for identification
57
What gradient generates the most microbial energy?
transmembrane ion gradients
58
how is the membrane energized?
by proton motive force
59
What are the two components of the transmembrane ion gradient?
F0 and F1
60
Is the F0 portion hydrophobic or hydrophilic?
hydrophobic because it traverses the membrane and conducts ions through the F1
61
Where is the F1 component found?
located on the interior surface of the membrane
62
What is the F1 components use?
to catalyze the hydrolysis of ATP and dehydration synthesis of ATP
63
What are the 4 ways to generate transmembrane ion gradients?
1. Respiration
2. Enzyme pumps
3. photosynthesis
4. scalar reactions
64
Where does eukaryotic respiration occur?
Within the mitochondrial membrane complex
65
What type of respiration is it when O2 is the final electron acceptor which results in reduction of O2 to water
aerobic
66
what type of respiration is present when any other molecule is the final electron acceptor?
anaerobic
67
In photosynthesis what does light energy activate and where does it come from
an electron from chlorophyl causing it to go down the ETC to ground state chlorphyll or NADP+
68
what is the equation for photosynthesis?
H2A+CO2-> A + carbohydrate
69
cyanobacteria is an example of what type of bacteria
photoautotrophic
70
what is an example of anoxygenic bacteria?
purple sulfur and nonsulfer bacteria
71
where are the substrates and products in scalar reactions?
in the same location or compartment
72
what is an example of scalar reaction bacteria?
oxalobacter formigenes which decarboxylate oxalate to form formate creating a proton gradient
73
what are the 3 pathways of central metabolism?
1. glycolysis
2. pentose phosphate pathway
3. TCA cycle
74
what is another name that the glycolysis pathway goes by?
Embden Meyerhof Parnas (EMP)
75
what does the glycolysis pathway yield
pyruvate, other precursor metabolites, 2 NADH, and 2 ATP
76
what is the pentose phosphate pathway for
an alternative route for converting G6P to triosephosphate
77
What does the pentose phosphate pathway yield?
2 additional precursors 2 NADH
78
The TCA cycle is fed from pyruvate through a linker precursor metabolite called...
Acetyl coenzyme A
79
What does the TCA cycle yield?
3 precursor metabolites, 4 NADH, 2 CO2
80
T or F: Bacteria and Archaea are able to reproduce sexually
false, only asexual and haploid
81
what is the generation time of E.Coli?
20 mins
82
what are the two pathways of the bacterial cell cycle?
1. DNA repliaction and partition
2. cytokinesis
83
what shape are bacterial chromosomes?
circular
84
what is the orgin of replication?
the site at which replication begin. There is only 1
85
what is a replisome?
a group of proteins needed for DNA synthesis
86
what does the replisome physically do?
pushes daughter chromosomes to opposite ends
87
what does MreB play a role in?
determination of cell shape and chromosome segregation
88
what happens if MreB is mutated?
the chromosomes do not segregate
89
what structure must form in septation?
Z ring
90
what kind of homolog is MreB?
an actin homolog
91
what type of homologue is protein FtsZ?
tubulin homologue
92
What forms from the polymerization of protein FtsZ?
the Z ring
93
What does the MinCDE system do in E.Coli?
limits the Z ring to the center of the cell
94
What does the MinCDE system do in general?
link the Z ring to the cell membrane
95
What is the function of proteins FtsA and ZipA?
anchor the Z ring to plasma membrane
96
What function does the FtsZ protein do?
form the z ring
97
what does the function FtsK hold?
chromosome segregation and seperation of chromosome dimers
98
what is the function of the FtsQLB protein?
a scaffold for assembly of proteins in peptidoglycan synthesis
99
what is the function of Ftsl and FtsW proteins?
peptidoglycan synthesis
100
what is the function of FtsN protein?
trigger constriction initiation
101
what do penicillin binding proteins (PBPs) do?
link peptidoglycan strands and catalyze controlled degradation for new growth
102
where does new peptidoglycan form in cocci divisome?
at the central septum
103
Do rods elongate before or after septation
before
104
what does FtsZ do in cocci divisome?
determines the site of cell wall growth and recruite PBP for synthesis of septum
105
what does MreB do in Rod divisome ?
determines cell diameter and elongation as Z ring forms in the center
106
what is a batch culture?
a closed system microbial culture of fixed volume
107
what is the lag phase?
the interval between inoculation of a culture and beginning of growth
the time needed for biosynthesis of new enzymes and to produce required metabolites before growth can begin
108
what is the log phase
rate of growth and division is constant and maximal
109
what growth is the most uniform and typically considered the healthiest?
log phase
110
what phase is typically considered balanced growth?
log phase
111
what are some reasons for stationary phase
nutrient limitation, limited oxygen, waste accumulation, critical population reached
112
What does RpoS protein assist?
Rna polymerase in transcribing genes for starvation proteins
113
what protein protects DNA
Dps
114
What is the equation for exponential growth
N=N02^n
N=final number
N0=initial cell number
n=the number of generations during the period of exponential growth
115
what is the equation for generation time
g=t/n
g=generation time
t=duration of exponential growth
n= number of generations
116
what manner do biofilms use to communicate?
quorom sensing
117
what type of bacteria produces AHL?
gram negative
118
what does AHL do once inside the cell?
induces the expression of target genes
119
what are cardinal temperatures?
the minimum, optimum, and maximum temperatures
120
where are psycrophiles found?
cold environments
121
where are thermophiles found?
in hot environments
122
what are the cardinal temperatures for psycrophiles?
opt:15
Max: 20
min: 0
123
what are the cardinal temperatures for psycrotolerant microbes
opt 20-40
124
what are some adaptations that microbes have to survive the cold?
more a helices, more polar amino acids, fewer week bonds
125
what is the optimum temperature for thermophiles
45-80
126
what is the ph optimum for neutrophiles
5.5-7.9
127
what is the optimum ph for acidophiles?
<5.5
128
what is the optimum ph for alkaliphiles
>8
129
what enzymes convert H2O2 to O2 and H2O?
catalase and peroxidase
130
what enzyme coverts 2 O2- to H2O2 and O2?
superoxide dismutase
131
what enzyme converts O2- to H2O2 without producing O2
superoxide reductase
132
what type of acid is contained in endospores
dipicolinic acid
133
what is the outer layer of endospre
exosporium
134
what ion is endospores enriched in
Ca2+
