exam 1 lecture 3 and 4 Flashcards
1
Q
shapes of bacteria
A
Spheres (cocci)
Rods (bacilli)-straight or bent
Spirals (Spirilla)
2
Q
what do all bacteria have
A
Nucleoid( chromosomal DNA)
Cytosol (polyribosomes, PR, carbs, inclusions)
Plasma membrane (phospholipids and PR)
Cell wall
3
Q
what do some bacteria have
A
Flagella(gram pos or neg) Fimbriae(pili)(gram-pos or neg) Capsule (gram pos and neg) Outer membrane (gram-negative bacteria) Endospores (gram-positive) Periplasm (gram-negative)
4
Q
Region in cytoplasm where genomic DNA is located (plus regulatory pr)
A
Nucleoid
5
Q
what is the nucleoid attached to
A
cell membrane and central structures of the cell
6
Q
what fills bacterial cytoplasm
A
ribosomes (50s+ 30s)
7
Q
provides shape to cell
A
cytoskeleton
8
Q
Granules that contains reserve materials(glycogen, lipids phosphates)
A
inclusion bodies
9
Q
what is the functional equivalent to organelles in Bacteria
A
Cell membrane
10
Q
What is the cellular membrane made of
A
Phospholipids and PR, lacks sterols (except mycoplasma)
11
Q
the place of active transport
A
Permeability barrier
12
Q
where energy is made in bacteria
A
on the cell membrane (Contains electron transport chain)
13
Q
role of receptor protein in the bacterial cell membrane
A
chemotaxis
14
Q
function of cell wall
A
physical protection from mechanical disruption or osmotic lysis
barrier against toxic chemical, bio agents
cell shape
15
Q
cell wall of gram positive bacteria
A
many layers of peptidoglycan, Teichoic Acid or lipoteichoic acid, special components for certain cells
16
Q
Polymer of glycerol phosphate or ribitol phosphate and various sugars, amino acids
A
Teichoic acid
17
Q
function of teichoic acid
A
unknown, but may help with secretion
18
Q
variation of TA that anchors cell wall to membrane through glycolipids in the membrane
A
Lipoteichoic acid
19
Q
structure of peptidoglycan
A
glycan chains that are crosslinked to one another by peptide side chains and pentaglycine interbridges
20
Q
lysozymes are found
A
present in tears, saliva, and mucus(the innate immune system)
21
Q
How lysozymes work
A
cleave beta 1-4 glycosidic bonds between NAG and NAM polysaccharides of petidoglycan
22
Q
what is penicillin effective against
A
Gram-positive bacteria
23
Q
how penicillin works
A
Blocks cell wall synthesis by inhibiting transpeptidase and carboxypeptidase enzymes that form crosslinks between glycan chains
24
Q
Gram Negative Bacterial cell wall
A
2 membranes and thin single layer of peptidoglycan between
25
since the outer membrane of the gram negative bacteria is impermeable, how do nutrients get into the cell
porins that allow diffusion of hydrophilic solute molecules and excludes harmful molecules from the environment
26
What does periplasmic space contain
contains a gel-like matrix
27
periplasmic space proteins are important for:
transport, chemotactic, and hydrolytic roles
28
Role of Lipoplysaccharides
Have a negative charge to protect against phagocytosis
29
what is found on the outer portion of gram negative bacterial cell walls
Lipoplysaccharides
30
parts of lipopolysaccharides
```
O antigen polysaccharide side chain
Core Polysaccharide
Lipid A(toxin)
```
31
What makes up the O antigen polysaccharide side chain
Linked sugars
32
Role of O antigen polysaccharide side chain
Antigen determinant
33
diveristy of LPS core polysaccharides
Similar between species
34
Phospholipid with glucosamine instead of glycerol as part of LPS in the outer membrane
Lipid A(toxic)
35
Smallest known bacterial species
Mycoplasma
36
Cell wall and membrane of Mycoplasma
No cell wall and membrane contains a sterol-like molecule
37
where Mycoplasma is foun
Usually osmotically protected environments as a parasite on hosts
38
what causes walking pneumoniae
Mycoplasma pneumoniae
39
A thick hydrophilic gel that surrounds the bacterial cell
Capsule (slime layer)
40
what are Capsules made of
Usually: polysaccharides
sometimes: polypeptiedes
41
Different between a capsule and slime layer
Capsule: discrete
| Slime layer: amorphous
42
Purpose of the capsule
protect bacteria from immune system
| Nutrients
43
Presence or absence of a capsule depends on
growth conditions
44
what types of bacteria have flagella
gram possitive and negative
45
Monotrichous, lophotrichous, Amphitrichous and peritrichous flagella
Mono: 1 flagella
Lophotrichous: many on one side
Amphitrichous: 1 on each side
Peritrichous: many flagella all over
46
Small thin hair-like projections with role of attachment
Fimbriae
47
Who has Fimbriae
both gram + and -
48
What is Fimbriae made of
Fimbrilin PR
49
Long thicc projections for attachment and DNA transfer
Pili
50
what is used to transfer DNA between Gram negative bacteria
Sex pili
51
What are Pili made of
pilin PR
52
Role of Endoscpores
Resist heat and germinate after centuries
53
Purpose of Spores
Survivial under adverse conditions
54
Small, dehydrated, metabolicaly quiescent form of bacteria that germinate when conditions are favorable
Endospores
55
Why are endospores produced
respond to nutrient limitation or a related time for tough times are coming
56
who makes endospores
environmental isolates( Bacillus species)
57
What are endospores made of
DNA surrounded by membranes/cortex
58
How can bacteria attach to human cells
Pili
59
what type of hereditary material is in Bacteria
Single of double standed DNA
60
how can a commensal be turned into a pathogen
acquisition of virulence genes
61
How is bacterial metabolism different than eukaryotic Metabolism
Faster, can use a greater diversity of energy, more diverse nutritional requiremnts, macromolecule synth is streamlined, and has unique processes
62
Catabolism
| Anabolism
breakdown
| Synthesis
63
When ATP, metabolic intermediates and pyruvate are fermented to lactic acid or alcohol
Embden-Meyerhof glycolytic pathway
64
Pathway that generates NADPH and Pentoses and ribose 5-phosphate(nucleotides)
Pentose phosphate pathway
65
Pathway that generates ATP from oxidative Phosphorylation
Krebs Cycle/TCA cycle/citric acid cycle
66
"material" starts for metabolism
PO4, Carbon, SO4, and NH3
67
Diffusion based on concentration gradients
Facilitated diffusion
68
Active transport needs what to occure
ATP cleaving
69
SUbstrate level phosphorylation
Transfer of electrons and protons via NAD+ directly to an organ acceptor to make characteristic end products
70
Respiration
substrate oxidation coupled to transport of electrons through a chain of carriers in the membrane to an acceptor molecule
71
what is the normal acceptor molexule in respiration
Oxygen
72
difference between aerobes and anaerobes
ability to rement or respire and how to cope with oxygen
73
What oxygen gets turned into for anaerobes
Hydogen peroxide or superoixde anions
74
when electrons and protens are transfered to O2 as a final acceptor
hydrogen peroxide
75
what is produced as an intermediate when O2 is reduced
superoxide anion
76
enzymes for Hydrgeon peroxide production
Catalase or peroxidase
77
enzymes for superoxide aion
superoxide dismutase
78
organism that lack catalase and superoxide dismutase are
strict anaerobes
79
require O2 to grow
Obligate aerobes
80
can not grow when O2 is present
Obligate anaerobes
81
can grow with and without O2 (Contain genes for fermentation and respiration)
Facultative aerobes
82
when do anearobic metabolism-fermentation, but can tolerate O2
Aerotolerant anerobes
83
Type of bacteria that mostly ferment sugar but can tolerate some O2
Streptococci
84
Otimal growth at low pH
acidophiles
85
Optimal growth at high pH
Alkaliphiles
86
Optimal growth at neutral pH
Neutraphiles
87
Require high Salt
Halophiles
88
Capable of growth in high sugar
Osmophiles
89
grow between 45-122 degrees celcius
Thermophile
90
TIme it takes for 1 bacteria to devide to 2
Doubling time
91
what is involved in doubling time
environment, expression of genes, bacterial type
92
Time when bacteria adapt to environment, while genes are being turned on to metabolise
LAg phase
93
bacteria grow logarithmically
Exponential phase
94
slope of line of exponential phase
growth rate-Td
95
where growth stops becuase nutrients are gone, or toxic buildup of toxic by-products
Stationary phase
96
introduces supercoils into DNA
DNA gyrase
97
Relaxes DNA supercoils
Topoisomerase
98
Steps to chromosomal replication
Initiation, elongation, termination
99
DNA replication direction of bacteria
Bidirectional
100
how is new DNA made
semi-conservatively (each daughter contains half new and half old dna
101
When a nucleotide is changed
Base Substitution
102
When a nucleotide is inserted
Insertion
103
When a nucleotide is deleated
Deletion
104
when a nucleotide chnage results in a stop codon
Nonsense
105
When a nucleotide change results in an an amino acid change
Missense
106
When a DNA sequence is abnormally copied
Duplication
107
When a base substitution has no effect on protein sequence
Silent
108
when insertion/ deletion occurs in a coding sequence
Frameshift
109
When a nonsense mutation occurs, it results in
a truncated PR
110
When does Homologous recombination occure
Anytime there is a source of recombinant DNA and strand breaks in the bacterial chromosome
111
what is needed for Homologous recombination
Donor DNA must hace large region of identical nucleotide sequence to host
REcipient cell must have recA gene
112
gene that controls Homologous recombination
recA
113
The ability to take up GNA from the environment
Natural transformation
114
transfer of plasmid DNA through sex pili
Conjugation
115
bacteria phge accidentally inject bacterial DNA into host bacterial cell
Transduction
116
DNA that can insert or excise itsself from the chromosome or plasmid
transposable elements
117
What can happen to DNA upon transformation
gets degraded by nucleases for raw material
| Integrated into the chromosome via recombo
118
When peptide pheromones produced by other bacteria are sensed by bacteria and turn on genes for competence
quorum sensing
119
mediates Natural transformation
quorum sensing
120
When do transposable elements cause a mutation
when the element inserts into the coding sequence of a gene
121
how large are antibiotic resistance or virulence genes
large
122
Problem with making mRNA and PRotein
energetically expensive
123
How do bacteria control when certain proteins are made
sense their environemt through quorum sensing
124
Binds to promoter loacted upstream of gene start codon
RNA polymerase
125
what determines activity of promoter and amount of mRNA that gets made
Strength of interaction of RNA polymerase and Promoter, and regulatory proteins
126
Multiple genes arranged together on the same mRNA transciprt expressed from the same promoter
Operon
127
how are Operons transcribed
Co-transcribed
128
Relation of transcription and translation in bacteria
coupled
129
Transcriptional regulation
promoter activity regulated by transcription factors, sigma factors, proteins etc
130
Post-transcriptional regulation
mRNA stability
131
Translational regulation
translation initiation
132
Post-translational regulation
Protein turnover
133
Regulates genes in response to an environmental stimuli
Two component regulatory system
134
The study of genes and how to determine what they do
Functional genomics; manipulate through mutations and knockouts
135
essential genes
can't be mutated for viability
136
genes that only are needed under certain conditions
dispensable genes
137
genes directly related to the ability of bacteria to cause disease
Virulence factors
