Midterm Flashcards
(136 cards)
1
Q
Robert Hooke
A
Micrographia (first book to show observations under a microscope)
2
Q
Van Leeuwenhoek
A
See microscopic life through microscope for the first time
3
Q
Louis Pasteur (4 things)
A
Fermentation
Vaccines can be created by weakening microbes
Disproved spontaneous generation (swan neck flask)
Pasteurization
4
Q
Germ Theory
A
Pasteur,Koch,others
Many diseases caused by microorganisms, can be passed from person to person
5
Q
Edward Jenner
A
Vaccinated a boy with cow pox to render immunity to smallpox
6
Q
Robert Koch
A
Germ theory
4 postulates
7
Q
Causes of anthrax, tuberculosis, and cholera
A
Bacillus anthracis
Mycobacterium tuberculosis
Vibrio cholera
8
Q
Koch’s postulates
A
Microorganism must be found in abundance in all organisms with the disease, and not in healthy ones
Microorganism must be isolated from organism and grown in pure culture
Cultured microorganism should cause disaese when put in healthy microorganism
Microorganism must be isolated from new host, and should be identical to orgininal causitive agent
9
Q
Joseph Lister
A
Antiseptics in surgery
10
Q
Fanny Hesse
A
Agar as culturing medium
11
Q
Alexander Fleming
A
Penicillin
12
Q
Which microorganisms can synthesize vitamin B12
A
Archaea and bacteria only
13
Q
Microorganism responsible for the plague
A
Yersinia pestis
14
Q
Characteristics of life
A
Metabolism Growth Reproduction Homeostasis Evolution Adaptation
15
Q
Cell membrane function
A
Homeostasis
Controls flow of molecules into and out of cell
16
Q
Proteins
A
50-55% dry cell weight
Composed of amino acids
Catalyze most cell reactions
Structural components
17
Q
Nucleic acids
A
RNA 15-20% dry weight
DNA 2-5% dry weight
18
Q
Lipids
A
10% dry weight
19
Q
Polysaccharides
A
6-7% dry weight
20
Q
When did the earliest microbes appear (origin of life)
A
3.5-4 billion ya
21
Q
First oxygen producing bacteria
A
3 billion ya
22
Q
Atmospheric oxygen
A
2 billion ya
23
Q
When did complex eukarya originate
A
1.5 billion ya
24
Q
Experiment which showed how microbial life arised
A
Miller
Showed organic molecules found in living cells could be synthesized from a mimicked primordial atmosphere
Boiling flask = ocean
Electrical sparks = lightning
Organic molecules including amino acids in collected sample
25
Yeast bacteria
Saccharomyces cerevisiae
26
Vibrio
Curved rod shaped bacteria
27
Spirilla
Spiral shaped bacteria
28
Pleiomorphic
Irreular shaped bacteria
29
FtsZ
Helps in cell division
| Monomers form a Z ring which directs cell wall synthesis and contracts as cells divide by releasing subunits
30
MreB
Provides structure during cell wall formation
Leads to elongated cylinder
Non-spherical bacteria
31
ParM
Dircts plamid movement during cell division
| Ensures each daughter cell gets a copy
32
Hypotonic
Greater solute concentration in cell
| Cell swells
33
Hypertonic
Greater solute concentration outside cell
| Cell shrivels
34
Symport
Both substances moving in the same direction through cell membrane
35
Antiport
Substances moving in opposite directions through cell membrane
36
Facilitated diffusion
Using a protein channel to move particles with the concentration gradient
No energy
37
Sec pathway
Pathway which proteins are exported through
SecB signal sequence
Delivery to SecA and then Sec YEG channel
38
Peptidoglycan composition
N-acetylglucosamine (NAG)
| N-acetylmuramic acid (NAM) with a small peptide chain
39
How is peptidoglycan made
NAM is made in the cytoplasm then linked to UDP then to bactoprenol
NAG is added
Bacteoprenol flips them to the periplasm
Polymeriztion and crosslinking
40
Bacitracin
Interferes with dephosphorylation of bactoprenol therefore interfering with peptidogylcan and cell wall synthesis
41
Lysozyme
Hydrolyzes beta1,4 linkages between NAG and NAM in bacteria
| Degrades cell wall
42
Lysostaphin
Acts on peptidogylcan crossbridge
43
Beta lactam antibiotics
Bind to penicillin binding proteins preventing them from crosslinking peptidoglycan
Make cells prone to cell bursting
Acts on growing cells
44
Beta lactamase
Can hydrolyze C-N bond in beta lactam ring rendering antibiotic ineffective
45
Gram positive
```
Purple stain
Thick peptidpglycan layer
Narrow periplasmic space
teichoic and lipoteichoic acids in peptidoglycan
Large pores in peptidoglycan
```
46
Gram negative
Pink stain
Thin peptidoglycan
Varying periplasmic space
Outer membrane with lipopolysaccharides (LPS)
anchored peptidogylcan by lipoproteins
Porins or TonB proteins transfer molecules to periplasmic space
47
Type________secretion system similar to flagella transports proteins directly from __________ through _________
III
Cytoplasm
Inner and outer membrane
48
Other motility strategies
Gliding motility
| Actin based motility (pushed by polymers of actin)
49
Other adhesion strategies
Stalks (tubular extensions of cell envelope)
| Polysaccharides (ex. Capsule)
50
Model fungi
Saccharomyces cerevisiae
Cell walls of chitin
Used to make bread,beer, etc.
51
Penicillin is made by __________
Penicillium chrysogenum
| Mould that appears in most homes
52
____________ species are of biomedical and industrial significance
Aspergillus
53
Model protozoa
Giardia lamblia
Old
Lacks mitochandria
Causes human disease (bever fever)
54
Model slime mold
Dictyostelium discoideum
| Protozoan
55
Model algae
Chlamydomonas reinhardtii
| Two flagella
56
Nitroimidazole
Antibiotic used for anaerobic bacteria and protozoan
Reacts with reduced ferredoxin
Reduced nitroimidazole intermediates form linkages with critical cysteine bearing enzymes deactivating them
57
Diseases caused by fungi and protozoa (eukaryal microbes)
Athletes foot, oral thrush, potato blight
58
Eukarya vs archaea nucleosomes
Eukarya: tetramer histone, 60 nucleotide length
Archaea: octaner, 160 nucleotide length
59
Archaeal plasma membrane
Gylcerol 1-phosphate rather than glycerol 3-phosphate
Isoprenoids instead of fatty acids
Ether not ester linkages
60
Archaeal cell wall
Pseudopeptidoglycan/pseudomurein
NAG and NAT subunits
Beta 1,3 linkages
L rather than D amino acids
61
Crenarchaeota
Archaeal phylum
20% of bacteria and archaea in marine environments
Thermophiles and hyperthermophiles (> 55 or 80 degrees)
Acidophiles
Barophiles (high pressures)
Many adaptations for survival
Mesophiles and psychrophiles (15-40 or <15 degrees)
62
Euryarchaeota
Methanogens
Reduce co2 to produce ch4 and water
Energy released to fix carbon
Found in human gut and swamps
63
Halophiles
Require NaCl at more than 1.5 M
Maintain high K+ concentration inside cell to offset high extracellular Na+ (to prevent denaturing proteins and DNA, high GC content and acidic proteins)
64
Nanoarchaeota
One of smallest genomes
| Possibly one of the smallest living organisms on earth
65
Proteobacteria
```
Gram negative
Flagellated
Similar to mitochandrial ancestor
MVP: E. coli, Yersinia pestis
Rod
```
66
Firmicutes
```
Gram positive
Low GC DNA content
Endospores
Round or rod
MVP: bacillus
Staphylococcus and streptococcus
```
67
Cyanobacteria
Gram negative
Oxygenic photosynthesis
Amcestor of chloroplast
No flagella
68
Actinobacteria
Gram positive
High GC DNA content
Common is soils
MVP: streptomyces (antibiotics)
69
Bacteroidetes
Gram negative
| Human microbiome
70
Evidence of endosymbiotic theory
Mitochnadria and chloroplasts resemble bacteria in shape and size
Double membrane consistent with ingestion
Own DNA more similar to bacteria than eukary
71
Viruses are non-living
Replicate with host cell machinery
Metabolically inert
No homeostasis
72
Viral capsid
Protein around genome
Can be helical (contains ssRNA)
Icosahedral (20 sided polygon)
73
Enveloped virus
Plasma membrane around capsid
| Mainly associated with animal viruses
74
Virus infection steps
```
Attachment
Entry
Gene expression and protein production
Genome replication
Assembly and exit host
```
75
Viral attachment
Uses attachment proteins
| Tail fibers, spikes, capsid, etc
76
Viral entry
Depend on host cell
Animal: receptor binding and endocytosis
Bacterial: injecting DNA through cell wall and membrane
77
Lytic viruses
Infect cell, replicate, then released from cell
78
Lysogenic phage
Can integrate their genome into host chromosome after entry instead of immediately lysing the cell
79
Baltimore classification
Seperates viruses based on genome structure and replication strategy (7 categories)
80
ICTV
Groups viruses into order, family, subfamily, genus, species
| Based on morphology, genome, replication, host range
81
Cultivating viruses: bacteriophages
Bacteriophages can added to liquid medium with bacteria to produce a lysate
Isolated with molten agar method
82
Cultivating viruses: animal viruses
Virus added to cultured cells
83
Where are most vaccines grow?
Chicken eggs
84
Purifying viruses
```
Differential centrifugation (centrifuge at low, medium, then high speed, virus in pellet)
Gradient centrifugation (tube with layers of sucrose, centrifuged, band of debris and band of virus)
```
85
Quantifying viruses
```
Plaque assay (virus diluted and placed on cells, count plaques)
Endpoint assay (amount of virus needed to induce cytopathic effect or to kill 50% of cells or subjects)
Direct count, EM (directly count)
```
86
Macronutrients to build macromolecules
C, N, P, O, S
87
Micronutrients to support biochemical processes
K, Na, Cl, Mg, Mn, Fe, Zn, Co, Mo, Cu
88
Anabolism
Biosynthesis, small to large molecules
89
Catabolism
Large to small molecules
90
3 things for metabolism to occur
Electron supply
Carbon supply
Energy supply
91
Phototroph
Captures light energy to make ATP
92
Chemotrophs
Capture energy from oxidation of reduced organic or inorganic compounds
93
Organotrophs
Acquire electrons from organic molecules
94
Lithotrophs
Acquire electrons from inorganic sources
95
Autotrophs
Acquire carbon from inorganic sources
96
Heterotrophs
Assimilate carbons from preexisting carbon forms
97
Prototrophs
Cam synthesize all macromolecular precursors from single carbon source
98
Auxotrophs
Unable to synthesize macromolecular precursors, must be supplemented with them in growth media
99
Catalase
Decomposes toxic hydrogen peroxide
100
Superoxide dismutase
Partitioning of superoxide radical into hydrogen peroxide and molecular oxygen
101
Selective media
Isolation of microbes with particular properties
| Ex crystal violet and bile salts inhibit gram positive bacteria
102
Differential media
Allows certain microbes to be recognized based on visual reactions in the medium
Ex. Neutral red and lactose
103
Measuring population growth
Direct count using a microscope slide or a Petroff-Hausser counting chamber
Viable cell counting by perfroming serial dilutions and counting colony forming units
Spectrophotometer to measure optical density
Chemostat (cell growth rate = dilution rate)
104
Phases of a growth phase
Lag
Exponential
Stationary
Death
105
CFU/ml equation
=(number of colonies)/ (dilution) x (volume plated in ml)
106
Generation time equation
=(time)/3.32 x (logNt - logN0)
107
Growth rate equation
= 3.32 x (logNt - logN0)/time
108
Equation to describe a bacterial population in the exponential phase
Nt =N0 X2^n
Where Nt = population at time t
N0 = initial population at time t = 0
n = number of generations that elapsed between t = 0 and time t
109
Equation for mean generation time (k)
k =n/t
110
Embden-Meyerhof-Parmas (EMP) pathway
Most common glycolytic pathway
| Glucose to 2 pyruvate, 2 ATP, 2 NADH
111
Entner-Doudoroff pathway
Alyernative to EMP
Glucose to 2 pyruvate, 1 ATP, 1 NADH, 1 NADPH
Entry point for sugars into metabolism
112
Pentose phosphate pathway
Glucose to 1 ATP and 2 NADPH
| Produces carbon sugar precursors for other pathways
113
Processes to oxidize NADH back to NAD+
Respiration (ETC) and fermentation
114
3 fermentation types
Lactic acid fermentation
Alcohol fermentation
Mixed acid fermentation
All produce NAD+
115
TCA/citric acid/krebs cycle
Oxidation of 1 molecule of pyruvate to produce 3 CO2 yields:
4 NADH, 1 FADH, 1 ATP
Twice this per glucose
116
ETC
As electrons carried by NADH and FADH are passed through molecules in the ETC with increasing reducing potentials, a proton gradient is generated which is used to produce up to 34 ATP via ATP synthase
Oxygen is the terminal electron acceptor in aerobic respiration
117
Protons pumped per NADH/NADPH
10
118
Protons pumped per FADH2
6
119
What powers the ETC and production of ATP
The proton motive force
120
2 steps of photosynthesis
```
Photophosphorylation (makes ATP)
Carbon fixation (dark), makes CO2 into organic molecules using ATP
```
121
Photophosphorylation
Uses photopigments like chlorophyll which make up photosystems to capture energy from photons and transfers it to electrons (bacteriochlorophyll in bacteria)
122
PS I and II
I or II used for anoxygenic photosynthesis
| Both used in oxygenix photosynthesis in chloroplasts and cyanobacteria
123
Calvin Cycle (dark reactions)
ATP and NADPH produced in light reactions used to produce carbon compounds from CO2
RuBisCO enzyme adds carbon from co2 to a 5 carbon, and the product is split to 3PG molecules which are converted to glyceraldehyde 3 phosphate used for biosynthesis
Uses 18 ATP, 12 NADPH per glucose
124
Amino acids are formed from _______
Many glycolysis, pentose phosphate, and TCA cycle intermediates
125
Lipids formed from________
TCA and glycolysis intermediates
126
Nucleotides formed from ______
Pentose phosphate intermediates
127
Bacteria, archaea and eukarya: Nuclear membrane
Bacteria and archaea no
| Eukarya yes
128
Bacteria, archaea and eukarya: organelles
Bacteria, archaea: rare/a few
| eukarya: yes, many
129
Bacteria, archaea and eukarya: plasma membrane
Bacteria and eukarya: similar
| Archaea: different from both
130
Bacteria, archaea and eukarya: RNA polym
Bacteria: single polymerase
Archaea: single polymerase similar to eukaryal polym II
Eukarya: polymerase I, II, III
131
Bacteria, archaea and eukarya: histones
Archaea and eukarya: yes
| Bacteria: histone like proteins
132
Components of LB broth
Peptone
Yeast extract
NaCl
133
LPS
Lipopolysaccharides
Lipids and polysaccharides
Stabilizes membrane of gram negative bacteria, illicits immune response in humans
134
Lipoteichoic acid
Lipid and polysaccharide
Illicits immune response in humans
Peptidoglycan layer of gram +
135
Peptidoglycan
Polysaccharide backbone crosslinked with peptides
| Maintains cell shape and provides structure
136
TonB receptors and porins
Proteins
Gram - outer membrane
TonB: Active transport across outer membrane
Porins: diffusion of nutrients and water
