Basic Bacteriology Flashcards
1
Q
what is a diplococci?
A
a bacterium that occurs as pairs of cocci
2
Q
shape of streptococci
A
live in pairs or chains of varying length
3
Q
shape of tetrad cocci
A
four balls
4
Q
shape of sarcinae
A
cube of four balls
5
Q
shape of saphylococci
A
a cluster of balls
6
Q
types of spiral bacteria
A
- Vibrio
- most common cause of food poisoning in Japan - Spirillum
-Ex: rhodospirillum - Spirochete
- capable of easy infection. Ex: lime disease
7
Q
what type of bacteria tend to live in hypotonic enviroments?
A
star-shaped and rectangular prokaryotes
8
Q
how big is a small subunit
A
30s
9
Q
how big is a small subunit
A
30s
10
Q
how big is a large subunit
A
50s
11
Q
how large is a complete ribosome
A
70s
12
Q
which structures are found in all bacteria
A
- Cytoplasm
- 70S Ribosomes
- Plasma membrane
- Nucleoid containing DNA
- Plasma membrane
13
Q
what is the purpose of the capsule in a prokaryotic cell?
A
to protect against phagosynthesis
14
Q
what is the purpose of the plasma membrane in prokaryotes
A
- make cell wall
- transport things in and out of the cell
15
Q
what is the purpose of the inclusions
A
important in adjusting the environment of the cell
16
Q
purpose of plasmid
A
- extral chromosomal dna
- non-essential coding of characteristics
- tend to be lost in the absence of selective pressure Ex: antibiotics
17
Q
purpose of pilli
A
- involved with gene transfer and attachment to surfaces Ex: teeth
18
Q
study slide
A
20
19
Q
definition of virulence
A
extent of pathogenity
20
Q
what is Peritrichous flagella
A
- having flagella uniformly distributed over the body
21
Q
what is Monotrichous and polar flagella
A
one flagellum at one pole
22
Q
Lophotrichous and polar flagella
A
multiple flagella located at the same spot on the bacteria’s surfaces
23
Q
what is Amphitrichous and polar flagella
A
a single flagellum on each of two opposite ends
24
Q
what is the motor that drives flagella driven by
A
a proton gradient
25
difference between a gram-negative and gram-positive flagella motor
the gram-negative bacteria have an outer membrane whereas the positive do not
26
what is the motor of the flagella held by
peptidoglycan
27
direction of clockwise flagella results in...
tumble
28
direction of counter-clockwise flagella results in...
run
29
Random movement toward an attractant causes a drop in
CheY-P levels, which allows CCW rotation and swimming.
30
what initiates a series of events lowering the CheY-P levels
Methyl-accepting chemotaxis proteins (MCPs)
31
reversable methylation of MCPs causes
desensitizes MCPs
32
demethylation of MCPs results in
sensitizes MCPs
33
definition of chemotaxis
refers to the migration of cells toward attractant chemicals or away from repellents.
driven by:
- methylation
- demethylation
- phospholation
34
biased random walk
enables bacteria to search for food and flee from harm
35
what are axial filaments
bundles of flagella which wrap around the cell body between the cell wall and the outer membrane
36
what is a biofilm
an assemblage of surface-associated microbial cells that is enclosed in an extracellular polymeric substance matrix
Ex: plaque on teeth
37
what happens to the flagella after biofilm is formed
the bacteria stop using them
38
why is cystic fibrosis chronic
because the formation of biofiliments are highly resistant to antibiotics
39
what is quorum sensing
a bacterial cell–cell communication process
40
what is a characteristic of encapsulated bacteria
shiny
41
characteristics of gram positive bacteria
gram reaction: blue stain
peptidoglycan layer: thick
teichoric acids: present
periplamic space: absent
outer membrane: absent
LPS content: none
lipid and lipoprotein content: low
flagellar structure: two rings in basal body
42
characteristics of gram negative bacteria
gram reaction: pink or red
peptidoglycan layer: thin
teichoric acids: absent
periplamic space: present
outer membrane: present
LPS content: high
lipid and lipoprotein content: high
flagellar structure: four rings in basal body
43
how do we test water for endotoxins
using limilus
44
what part of a bacterial is an endotoxin
the Lipopolysaccharide
45
what part of the bacteria does penicillin attack
the teichoic acid structures
46
what does lysosyme do
breaks down peptidoglycan
47
penicillin inhibits the formation of what enzyme?
transpepidase
48
penicillin inhibits the formation of gram-positive bacteria by
inhibiting peptidoglycan production
49
gram positive bacteria lose s layer when
they are transferred from culture to culture
50
function of porin in gran negative bacteria
The porins act as molecular filters for hydrophilic compounds
51
what is a protoplast
bacterial cell without cell wall
52
what is a sheroplast
a bacterium or plant cell bound by its plasma membrane, the cell wall being deficient or lacking and the whole having a spherical form.
53
where is the electron transport system located?
in the plasma membrane
54
Membranes have approximately equal parts of
phospholipids and proteins.
55
what is the structure of phospholipids
glycerol with ester links to two fatty acids and a phosphoryl head group
56
what are the two layers of phospholipids in the bilayer called?
leaflets
57
The structure that defines the existence of a cell is the
cell membrane.
58
what is the function of a hopanoid
intercalate into phospholipid bilayers and modulate the fluidity of membranes by interacting with their complex lipid components.
59
calcium heat shock is used to
used to introduce foreign DNA into a host cell. The concept of the technique is to render cells competent using CaCl2 to allow for introduction of plasmid.
60
what are zones of adhesions
area of a lipid bilayer where inner and outer leaflets join
61
what is Simple Diffusion
Simple diffusion is an unassisted type of diffusion in which a particle moves from higher to a lower concentration.
62
what is Facilitated Diffusion
the transport of substances across a biological membrane through a concentration gradient by means of a carrier molecule(noinputofenergy)
63
aquaporins
transmembrane diffusion of water
64
what is passive transport
molecules move along their concentration gradient does not require energy
65
what is Active transport
molecules move against their concentration gradient also requires energy
66
Group translocation is
process where a molecule crossing the cell membrane not only gets transported but also gets transformed in itself
67
The phosphotransferase system (PTS) present in all bacteria. is an example of group translocation. what is its function?
- It uses energy from phosphoenolpyruvate (PEP) to attach a phosphate to specific sugars.
- The system has a modular design that accommodates different substrates.
68
what is a storage granule
- Glycogen, PHB, and
PHA, for energy
- Sulfur, for oxidation
69
what are magnetosomes
- Membrane-embedded crystals of magnetite, Fe3O4
- Orient the swimming of magnetotactic bacteria
70
what are magnetosomes
The magnetosome is defined as an intracellular organelle consisting of a single-magnetic-domain crystal of a magnetic iron mineral enveloped by a lipid-bilayer membrane that contains proteins that are unique to it.
71
the process of endospore formation is called
sporulation
72
six steps of sporulation
- Spore septum begins to isolate newly replicated DNA and a small portion of cytoplasm.
- Plasma membrane starts to surround DNA, cytoplasm, and membrane isolated in step 1.
- Spore septum surrounds isolated portion, forming forespore.
- Peptidoglycan
layer forms between membranes.
- Spore coat forms.
- Endospore is freed from cell.
73
function of endospore
Endospores ensure the survival of bacteria in adverse environmental conditions
74
what is sigma-F
a protein that enhances transcription
75
what are the proteins that coat dna in endospores
small acid soluble proteins (SASP)
76
endospores exist in what kind of environment
Endospores exist in a cryptobiotic state
77
what are bacteriocins
toxins produced by bacteria to inhibit the growth of similar or closely related bacterial strain(s)
78
what is the exosporium
The exosporium is the outer surface layer of mature spores
79
ER is continuous with..
membrane envelope
80
what is the purpose of pores on nuclear membrane
transports things in and out of nucleus
81
FtsZ = forms a
“Z-ring” in
spherical cells
82
MreB = forms a
coil inside rod-shaped cells
83
CreS “crescentin” = forms a
polymer along the inner side of crescent-shaped bacteria
84
purpose of smooth er
detoxification and lipid synthesis
85
what is the golgi complex
The Golgi complex prepares proteins and lipid (fat) molecules for use in other places inside and outside the cell
86
what does the mitochondria have
- circular dna and 70s ribosomes
- the dna is maternally inherited
87
The Theory of Endosymbiosis
States that some organelles evolved from a symbiosis in which one cell of a prokaryotic species was engulfed by and lived inside of a cell of another species of prokaryote
88
what is the plasma membrane
The plasma membrane, also called the cell membrane, is the membrane found in all cells that separates the interior of the cell from the outside environment
89
what is the endoplasmic reticulum is involved in what synthesis
a network of membranous tubules within the cytoplasm of a eukaryotic cell, continuous with the nuclear membrane. It usually has ribosomes attached and is involved in protein and lipid synthesis
90
what is a lysosome
A lysosome is a membrane-bound cell organelle that contains digestive enzymes
91
what is a peroxisome
A peroxisome (IPA: [pɛɜˈɹɒksɪˌsoʊm]) is a membrane-bound organelle, a type of microbody, found in the cytoplasm of virtually all eukaryotic cells.
92
which genus makes more capsules given sugar
genus leubonostoc
93
what are the characteristics of Staphylococcus
- Facultative anaerobes
- Cocci in clusters
- S. aureus
94
Streptococcus characteristics
- Aerotolerants
- Cocci in chains
- S. pneumoniae
- S. pyogenes
