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MT I Flashcards

1
Q

Are microbes unicellular or multicellular?

A

They are unicellular but some can be multicellular

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1
Q

What are microbes/microorganisms?

A

These are bacteria that you can’t see with the naked eye but they are present everywhere (ubiquitous)

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2
Q

What is a culture?

A

These are a group of cells that are grown in a nutrient medium

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3
Q

What is a medium?

A

A nutrient solution

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4
Q

What is a colony?

A

A collection of millions of cells on a spot on a plate

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5
Q

How do nutrients get to humans?

A

They are uptaken by the microbes and passed on to humans

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6
Q

When did microbes arise?

A

3.8 billion years ago

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7
Q

What were the conditions during the first 2 billion years?

A

Anoxic or unoxygenated with only N2 and CO2

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8
Q

What happened following the arrival of microbes?

A

Conditions became oxygenated

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9
Q

What were the first phototrophs that made oxygen?

A

Anoxic

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10
Q

What do cyanobacteria do?

A

They produce oxygen

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11
Q

What did microbes give rise to?

A

The 3 domains: archaea, eukarya, and bacteria

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12
Q

What is it called when microbes can live in high temperature, very low pH etc.,?

A

Extremophiles

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13
Q

How did they find out about microbes?

A

Stromatolites

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14
Q

What are dead zones?

A

These are regions where the microbes uptake all of the O2 and the remaining aquatic life die

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15
Q

What is microbial ecology?

A

The study of microbes and the environment

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16
Q

What was the leading cause of death in the 20th century?

A

Pathogens and infections from bacteria

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17
Q

What are nitrogen fixing bacteria?

A

They exist in the nodules of the roots in legumes and convert N2 to NH3

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18
Q

Are microbes only good or bad?

A

No, some are bad ie., pathogens and some are good ie., yeast which ferments foods

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19
Q

What did Robert Hooke do?

A

He coined the term cells

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20
Q

What did Anton Van Leuweenhoek do?

A

He used his own bodily fluids and cells and looked at them under a microscope the first to see RBC and sperm cells

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21
Q

What was the limiting factor of Leuweenhoek’s microscope?

A

Resolution

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22
Q

What did Louis Pasteur do?

A

He explored the role of microbes in fermentation and vaccines

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23
Q

What was the spontaneous generation theory?

A

That inanimate objects are able to randomly produce living things

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24
Q

How did Pasteur reject the spontaneous generation theory?

A

Through the swan-neck flask experiment

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25
Q

What is the swan-neck flask experiment?

A
  1. Solution was put in the flask
  2. Used heat to make the swan-neck
  3. Microbes grew in the crook of the flask
  4. Any solution that spilled in the swan neck area became putrified
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26
Q

What did Robert Koch do?

A

He establish the Koch Postulates which are criteria that can be used to link the cause and effect betwen the bacteria and the disease

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27
Q

What are the Koch Postulates?

A
  1. It is consistent among the unhealthy organisms and not present in the healthy organisms
  2. Grown in a pure culture
  3. When injected in healthy animals it causes the diseases and terminates them
  4. The isolated pathogen must be the same as the original
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28
Q

What solids did Koch use?

A

Potato slices but they oxidized and fermented so he eventually switched to agar

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29
Q

What is the downside of agar?

A

It inhibits certain microbial activity

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30
Q

What did Sergei Winogradsky do?

A

He established the role of microbes in biogeochemical cycles

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31
Q

What are chemolithotrophs?

A

These are organisms that use chemical energy in order to produce inorganic material

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32
Q

What is made in soiled foods?

A

Lactic acid

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33
Q

What is the enrichment culture technique?

A

For the cells to grow the medium must have a culture

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34
Q

What was initially thought to have the role of DNA?

A

Proteins; DNA were thought to be too simple

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35
Q

Which experiments proved DNA to be the hereditary material?

A
  1. Griffith’s experiment - where the S strain DNA from dead/diseased cells inserted into the healthy cells converted it from healthy to diseased
  2. Avery and Macleod - They used RNAse, DNAse, and Protease to destroy one of the 3 and the transforming agent was determined to be DNA
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36
Q

Which universal sequence is used to establish an evolutionary relationship?

A

16s rRNA

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37
Q

What was Haeckle’s Theory?

A

The universal tree of life

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38
Q

What is the universal tree of life?

A
  1. Monera - unicellular organisms at the base
  2. More complex organisms at the branches near the top
  3. Plantae, animalia, and protista
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39
Q

What were the traits for 16s rRNA to be chosen?

A
  1. Adequate length
  2. Functionally constant
  3. Mutates slowly
  4. Universal
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40
Q

How was 16s rRNA sequenced?

A
  1. Isolate rRNA
  2. PCR amplify
  3. Sequence via overlaps
  4. Generate a tree
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41
Q

How did Carl Woese modify the universal tree of life?

A

Made 3 domains: archaea, eukarya, and bacteria

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42
Q

What else was a part of the universal tree of life?

A

The idea that advancement occurs as you go up the tree

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43
Q

What is genomics?

A

Studying the genetic material of an organism or a species

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44
Q

What is metagenomics?

A

Studying the genetic material taken from the environment

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45
Q

What is the relationship between similarity and homology?

A

They are not interchangable - a sequence can be similar without homology and vice versa

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46
Q

What is an ortholog?

A

Sequences that share a common ancestor and function

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47
Q

What is a paralog?

A

Duplicated sequences that accumulate mutations and evolve into having different functions

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48
Q

What is an assumption of phylogeny?

A

That the genetic material is transferred from one generation to the next

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49
Q

How is the assumption violated?

A

Microbes can undergo horizontal gene transfer and transfer genetic material to unrelated species

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50
Q

What system does nomenclature follow?

A

Binomial system

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51
Q

What is the binomial system for naming?

A

Genus name first = noun
Species name second = adjective

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52
Q

What does a >98.6% cut off tell you?

A

These species are similar based on the 16s rRNA

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53
Q

What does the <97% cut off tell you?

A

These species are different based on the 16s rRNA

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54
Q

What is the problem with the 16s rRNA?

A

It is not a perfect rule there can be a high similarity but sometimes this cut off can underestimate the number of species because there can be more different species

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55
Q

What is ANI?

A

Average nucleotide identity - this is a method of determining how similar the given genome from 2 organisms are MOST IMPORTANT

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56
Q

How do you generate ANI?

A
  1. Fragment the genome
  2. Align the gene with its ortholog to genome 2
  3. Calculate ANI
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57
Q

What is the ANI for ancestrally linked species?

A

> 96%

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58
Q

What is the ANI for different species?

A

<96%

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59
Q

How can you generate a new species?

A
  1. Species, genus name
  2. Detailed distinguishing traits
  3. Published
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60
Q

What is an OTU?

A

In soil it is an operational taxonomic unit and based on the percent homology between sequences the fragments can be grouped together in an OTU

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61
Q

Where did eukarya form from?

A

The divergence of eukarya from archaea

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62
Q

What is the endosymbiotic theory?

A

That the archaea engulfed a prokaryote ie., mitochondria and chloroplast which gave rise to a eukaryote

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63
Q

What is the symbiosis theory?

A

That the arachea developed a symbiotic or a mutally benefical relationship with the bacteria and then they continued to live and that gave rise to the eukarya

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64
Q

What does the presence of the mitochondria do?

A

Increase respiratory capacity

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65
Q

What is the evidence for the endosymbiotic theory?

A
  1. Chloroplast and mitochondria are the same size as bacteria
  2. Circular DNA with rRNA
  3. Have their own genes and genome
  4. Mt = Proteobacteria phyla and the Ch = Cyanobacteria phyla
  5. Antibiotic for bacteria inhibt both
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66
Q

Are microbes equally diversed?

A

No they are restricted to cetain areas based on nutrient availability

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67
Q

What is an ecosystem?

A

A nutrient rich area where animals, plants, microbes etc., interact with the abiotic material and an ecosystem consists of many. habitats

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68
Q

What is a habitat?

A

Part of an ecosystem that is best suited for one of the population

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69
Q

What does microbe activity depend on?

A

The species present

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70
Q

What does the growth rate depend on?

A

The nutrient available

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71
Q

What is a population?

A

A group of the same species in one location that can be descendants of a common ancestor

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72
Q

What is a community?

A

A web of coexisting microbial populations

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73
Q

What is species richness?

A

A measure of species diversity

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74
Q

What is species abundance?

A

A measure of the number of each species

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75
Q

What is a guild?

A

Metabolically similar populations use the same resources and habitats

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76
Q

What is a niche?

A

These are the habitats and resources shared by a guild

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77
Q

What is a collection of guilds?

A

A community

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78
Q

What are chemoorganotrophs?

A

These are organisms that oxidize organic matter to organic carbon ie., CO2

Heterotrophs

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79
Q

What are chemolithotrophs?

A

These are organisms that oxidize inorganic matter to organic carbon ie., CO2

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80
Q

What are chemolithotrophs the same as?

A

Autotrophs

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81
Q

How do the layers of guilds change?

A

Through the changing environment with depth

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82
Q

Which bacteria are used in the N2 cycle?

A

Chemolithotrophic and chemoorganotrophic bacteria

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83
Q

What is a realized niche?

A

This is the primary environment where the organism is successful

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84
Q

What is a fundamental niche?

A

This is the secondary environment where the organism may also live

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85
Q

Where is the O2 concentrated in a soil particle?

A

Outside with 21%

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86
Q

Where is the soil O2 free?

A

In the centre

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87
Q

Why is it hard to grow microbes in the lab?

A

1.) Resources and conditions are suboptimal
2.) Not uniform nutrient distribution
3.) Microbes grow in mixed population
4.) Competition for resources
5.) Syntrophy

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88
Q

What is syntrophy?

A

When organisms can’t accomplish goals on their own so they work together

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89
Q

What is a planktonic microbe?

A

These are free flowing bacteria

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90
Q

What is the benefit of attaching to surfaces?

A

Expend less energy because the nutrients come to the microbes

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91
Q

What types of surfacces can the microbes attach to?

A

Biotic or abiotic

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92
Q

What is a biofilm?

A

This is a surface that microbes attach to and then a polysaccharide matrix coats them and prevents them from detatching and the biofilm can consist of a multitude of species

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93
Q

Which growth is more extensive biofilm or planktonic?

A

Biofilm because the nutrients flows to it

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94
Q

Why do biofilm form?

A

1.) As a form of self defense against pathogen penetration and phagocytosis
2.) Stick to nutrient rich and favorable niches
3.) Facilitate cell-to-cell communication for horizontal gene transfer

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95
Q

Where do biofilms form?

A

Virtually anywhere that can support microbe growth which is why it is considered the default

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96
Q

What can genes in biofilms express?

A

Antibiotic resistance

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97
Q

Where is the growth rate slower in a biofilm?

A

In the matrix

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98
Q

What is a microbial mat?

A

These are regions of layered microbes that are nutrient rich and contain guilds which are governed by light and nutrient availability

  • Form due to the lack of grazing
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99
Q

Which bacteria are the most abundant in mats?

A

Phototrophic (cyanobacteria) and chemolithotrophic bacterias

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100
Q

What are cyanobacteria also classified as?

A

Extremophiles

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101
Q

What happens during the day?

A

Intense O2 at the surface activates surfacte reduction in lower regions

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102
Q

What happens when O2 and H2S mix?

A

The substrates are consumed from phototrophic and chemolithotrophic bacteria

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103
Q

What happens at night?

A

Photosynthesis stops and the mat becomes anoxic as the H2S accumulates and bacteria move with the chemical shifts

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104
Q

What conditions make a mat a stromatolite?

A

High salt and high temp

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105
Q

What do cyanobacteria do?

A

They are primary producers and autotrophs so they take the light and make new organic molecules from CO2

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106
Q

How do iron rich mats form?

A

They form via chemolithotrophic oxidizing bacteria

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107
Q

What are the 2 types of soil?

A

1.) Mineral soil where rock and inorganic material is weathered

2.) Organic soil from bogs and marshes are weathered

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108
Q

How much of soil is inorganic material?

A

40%

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109
Q

How much of soil is organic matter?

A

5%

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110
Q

How much of soil is air and water?

A

~50%

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111
Q

How much of soil is a micro/macroorganism?

A

5%

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112
Q

What are the limiting nutrients of soil?

A
  • Inorganic material
  • Water
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113
Q

How is a species defined?

A

As having a larger than 3% sequence difference in 16 srRna so %97>

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114
Q

Which type of body of water has more microbial diversity?

A

Unpolluted, undisturbed, soil supports high prokaryotic diversity

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115
Q

What species survive best during preturbations of soil?

A

Species that are more competitive in disturbed soil so diversity decreases

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116
Q

What is the difference between marine and freshwater environments?

A

The nutrient availability

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117
Q

What is a water column?

A

These are a collection of stratitfied levels of water with varying O2 content

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118
Q

What is the transition zone?

A

The area where the water transitions from hot to cold

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119
Q

What are oligotrophs?

A

These are microbes that survive in scarce nutrient conditions

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120
Q

What is the open ocean environment like?

A

Constant colder temperature than freshwater

121
Q

What is the biogeochemical O2 demand?

A

The O2 consuming capacity of a body of water

122
Q

What is the pelagic zone?

A

An open ocean with O2 but lacks inorganic material

123
Q

Where are the phototrophs more abundant open ocean or freshwater?

A

Freshwater x10

124
Q

What are the communities of microbes in the ocean?

A

1.) Algal bloom causing bacteria
2.) Summer time community bacteria in the upper water column
3.) More stable deepwater community

125
Q

What are pelagibacter?

A

These are small oligotrophic bacteria found in the pelagic zone

126
Q

How are pelagibacter able to survive?

A

1.) Small size
2.) High SA:V
3.) Needs limited nutrients
4.) Expends less energy

127
Q

What happens to the abundance of bacteria with depth?

A

It decreases

128
Q

Where does the pelagic zone extend to?

A

200m

129
Q

What happens to 50% of the oceans carbon?

A

Archaea and pelagibacter consume it via photosynthesis

130
Q

What do planktonic microbes do for oceans?

A

They regenerate material

131
Q

What is SAR11?

A

This is a group of pelagibacter that are chemoorganotrophs and are the most abundant

132
Q

What makes SAR11 successful?

A

1.) Increased nutrient transport
2.) Increased [substrate]
3.) Increased processing

133
Q

What is in the pelagibacter genome?

A

It contains a pigment gene called rhodopsin which converts light energy to ATP

134
Q

Is proteorhodopsin a phototroph?

A

No, but it is benefitted from it

135
Q

What happens to enzymatic activity when the temperature increases?

A

It increases due to the increase in molecular movement

136
Q

What happens at the max temperature?

A

Proteins irreversibly denature

137
Q

What is the optimum range for psychrophiles?

A

<15 degrees

138
Q

What is the optimum range for mesophiles?

A

15 - 45 degrees

139
Q

What is the optimum range for thermophiles?

A

45 - 80 degrees

140
Q

What is the optimum range for hyperthermophiles?

A

> 80 degrees

141
Q

Which one is the most common?

A

Mesophiles

142
Q

Do psychrotolerant bacteria grow well?

A

No

143
Q

How do psychrophile proteins remain stable?

A
  • More alpha helices (more flexible) than beta sheets
  • More polar and less hydrophobic amino acids and fewer weaker bonds
  • More unsaturated bonds
144
Q

What are hydrothermal vents?

A

These are regions of terrestrial environments that have hot springs with extremely hot conditions containing chemoorganotrophs and chemolithotrophs which only archaea and bacteria can withstand

145
Q

What happens as boiling water leaves the hot spring?

A

It gradually cools and makes a gradient and at the cool ends is where the microbes grow

146
Q

How can proteins stabilize against the heat?

A
  • More ionic bonding between acidic and basic amino acids
  • More hydrophobic centers which prevent unfolding
  • Producing polar solvents to stabilize proteins
  • More saturated bonds
  • Fewer unsaturated bonds
147
Q

What adaptations do hyperthermophiles have?

A
  • Monolayer not a bilayer
  • Covalently link the monolayer with isoprenes not fatty acids
  • Ether bond not ester
148
Q

What adaptations match those of a hyperthermophile?

A

Archaea

149
Q

What are many fungi and bacteria?

A

Acidophiles

150
Q

What happens without the stability from the PMF?

A

The cell lysis

151
Q

What are some alkaliphiles?

A

Halophiles

152
Q

Alkaliphiles have a problem the ETC pumps H+ out and the proton pump brings H+ in because of that there is no charge gradient for ATPase to activate what does it do?

A

When a H+ is pumped out a Na+ ion is pumped in this is the Na/ ATPase pump or Na motive force

153
Q

What happens when water binds to solute?

A

It becomes less available

154
Q

What is aw?

A

Water availability is expressed in terms of water activity which is the ratio of the vapor pressure of air in equilibirum with a solution compared to the vapor pressure of pure water aw = 1

155
Q

Where does water go?

A

Water diffuses to where there is more solute and less water

156
Q

What is positive water balance?

A

When a cell is in a hypotonic solution

157
Q

What are extreme halophiles?

A

Organisms that love salt

158
Q

What are osmophiles?

A

These are organisms that can grow in high sugar conditions

159
Q

What are xerophiles?

A

These are organisms that can grow in very dry conditions

160
Q

What happens when water is bound to soil?

A

Reduces aw

161
Q

What happens when an organism is moved from a medium of high aw to low aw?

A

Solute concentration increases to maintain positive water balance

162
Q

How do bacteria get more solute?

A

Compatible solute method and synthesize their own

163
Q

How do archaea get more solute?

A

Import

164
Q

What are microaerophiles?

A

Organisms that prefer O2 at levels less than atm <21%

165
Q

What are anaerobes?

A

Organisms that do not need O2

166
Q

What are facultative aerobes?

A

These are organisms that under specific conditions they can use another nutrient source besides O2

167
Q

What are obligate anaerobes?

A

O2 is damaging and harmful to these organisms

168
Q

What are aerotolerant anaerobes?

A

These are organisms that are indifferent to O2 can grow in the presence and absence

169
Q

What happens to the O2 in a test tube?

A

It decreases as it is consumed so you have to shake it

170
Q

What is the problem for anaerobes in a test tube?

A

Not the O2 being absent but present

171
Q

What is used in the test tube?

A

Thioglycolate broth that contains a reducing agent that can convert the remaining O2 to H2O

172
Q

Why is O2 toxic?

A

When the bacteria are unable to process the harmful byproducts

173
Q

What do catalase and peroxidase do?

A

They attack H2O2 and make O2 and H2O

174
Q

What do superoxidase dismutase do?

A

Attacks superoxide anion to make H2O2 and O2

175
Q

What do some organisms that lack dismutase use?

A

Mn

176
Q

What are the 3 main functions of the cytoplasmic membrane?

A

1.) Selectively permeable membrane
2.) Protein binding site
3.) Generate energy e.g., PMF

177
Q

What makes the PMF?

A

The H+ concentration gradient forms which also leads to a charge gradient which generates a proton motive force and powers ATP synthesis

178
Q

What can pass through the membrane?

A

Small or weakly polar molecules, or dissolved molecules

179
Q

What structural adaptations do Archaea have?

A
  • Monolayer
  • Ether bonds
  • Isoprenes instead of fatty acid tails
180
Q

What are the hydrophobic groups?

A

Fatty acid tails

181
Q

What are the hydrophilic groups?

A

Glycerol bound phosphate heads that either face the outside or the inside

182
Q

What happens to the larger molecules?

A

Since they can’t simply diffuse in they build up at the membrane and have to be transported against the concentration gradient using energy

183
Q

What is a simple transport system?

A

A system that consists of a transmembrane protein which consists of 12 domains of a polypeptide that makes a channel and solute is transported in the cell

184
Q

In a simple transport system how is the solute brought in?

A

The cell complex acts like a gate where solute binding opens the gate

185
Q

What drives simple transport?

A

PMF

186
Q

What is a symport?

A

When molecules (H+ and solute) are travelling in the same direction

187
Q

What is an antiport?

A

When molecules (H+ and solute) are travelling in the opposite direction

188
Q

What is an example of a simple transport?

A

Lac permease

189
Q

What happens as each lactose enters the cell?

A

PMF decreases

190
Q

How does group translocation differ from simple transport?

A

1.) A different energy source is used besides ATP
2.) The transported solute is modified upon transport

191
Q

What is the ABC transporter?

A

ATP binding cassette transporter consisting of 3 binding proteins: binding proteins, transmembrane protein, and ATP protein

192
Q

How does the cell respond to turger pressure?

A

The cell walls form in Gram positive and negative to retain cell rigidity and cell shape to prevent the cell from lysing

193
Q

What are the key features of a Gram positive bacteria?

A
  • Large cell wall containing peptidoglycan
  • Thin cytoplasmic membrane
194
Q

What are the key features of a Gram negative bacteria?

A
  • Thin cell wall
  • Outer and inner membrane
195
Q

What determines the reaction with the Gram stain?

A

The thickness of the cell wall

196
Q

What is the structural makeup of peptidoglycan?

A

1.) Alternating N-acetylglucosamine and N-acetylmuramic acid that are linked by a B-1,4-linkage

2.) Peptide cross linking the peptidoglycan chains with L-alanine, D-alanine, DAP, and D-glutamic acid for Gram negative bacteria Gram positive have a string of glycine

197
Q

Can Gram stain describe Archaea?

A

No because they lack cell walls like eukarya only bacteria

198
Q

What kind of structure do Gram positive have?

A

3D with horizontal and vertical peptide cross-links which form an interbridge

199
Q

What is teichoic acid?

A

This is an acidic molecule that is present in Gram positive bacteria it embed in the cell wall and are attached to glucose or D-alanine

200
Q

What do lysozymes do?

A

They destroy preexisting peptidoglycan

201
Q

What does penecillan do?

A

Prevents the formation of peptide links between new peptidoglycan molecules inhibits transpeptidase

202
Q

What do Archaea have instead of cell walls?

A

S layers which form the outermost layer

203
Q

What is the function of the S layer?

A

Prevents cell lysis due to turger pressure

204
Q

What is the outer membrane of Gram negative bacteria made up of?

A

Lipid bound polysaccharides

205
Q

What does LPS contain?

A

Lipid A and porin

206
Q

What does lipid A do?

A

It causes endotoxins ex., salmenella and E.coli in foods (diahrea, vomitting, etc.,)

207
Q

What is the role of LPS?

A

1.) Facilitate surface recognition
2.) Strengthen the cell wall

208
Q

What do the porins do?

A

Causes non specific entrance of solutes into the cell

209
Q

What is the purpose of the periplasm?

A

This is a region between the outer membrane and cell wall in Gram negative bacteria that keeps the extracellular proteins close to the cell

210
Q

Which other layer can form a periplasm?

A

The area between the S layer and cytoplasmic membrane in Archaea form a periplasm equivalent

211
Q

What is the role of the FtsZ ring?

A

To maintain cell shape

212
Q

How is more peptidoglycan made?

A

By breaking down the old

213
Q

What is bactoprenol?

A

A lipid carrier that is hydrophobic and is bonded to N-glucosamine and N-muramic acid to make lipid II

214
Q

What does bactoprenol do to transport peptidoglycan precursors through flippase (ABC transpoter)?

A

Make it more hydrophobic

215
Q

What is the process of making new peptidoglycan?

A

1.) Flippase transports lipid II across the cytoplasmic membrane to the cell wall growing point
2.) Autolysin breaks the glycolytic bond in the pre-existing peptidoglycan
3.) Transglycosylate makes new glycolytic bonds linking the new and old inhibited by vancomycin
4.) Transpeptidation leads to the cross linking of 2 peptide chains inhibited by vancomycin and penecillin

216
Q

What does transglycosylase do?

A

Lipid II interacts with transglycosylase which inserts peptidoglycan into the growing cell wall

217
Q

What does autolysin do?

A

Hydrolyzes and breaks the bonds between N-acetylglucosamine and N-muramic acid in the backbone to make gaps to insert the precursor is not inhibited by beta lactam

218
Q

What needs to happen to prevent autolysis?

A

Coordination of the autolysin and precursor availability

219
Q

What is transpeptidation?

A

The formation of cross links between glycan chain residues

220
Q

What step do antibiotics inhibit?

A

Transpeptidation - only impacts the bacterial cells humans do not have peptidoglycan because there is no cell wall

221
Q

Which activity does penecillan/beta lactam antibiotics not inhibit?

A

Transglycosylase and autolysin

222
Q

Which proteins have both transglycosylase and transpeptidase activity?

A

aPBP and bPBP

223
Q

Why is cell division controlled?

A

To ensure that daughter cells have equal amounts of genetic material

224
Q

What are the FtsZ proteins?

A

These proteins synthesize a ring at the future site of the septum for cell budding

225
Q

Where does the cell plate come from?

A

When the FtsZ ring binds to the cytoplasmic membrane and forms the divisome

226
Q

What is MinG?

A

The polymerized version of FtsZ which recruits other proteins like ZipA, FtsA

227
Q

What is ZipA?

A

Anchors FtsZ to the cytoplasmic membrane and stabilizes it

228
Q

What is FtsA?

A

Acts as an ATPase

229
Q

What is FtsI?

A

Is a peptidoglycan synthesizing proteins

230
Q

When does the divisome form?

A

3/4 into cell division

231
Q

What is FtsI?

A

A penicillan binding protein that is inhibited by penicillan binding to prevent peptidoglycan synthesis

232
Q

What is Min C and D?

A

They are proteins that guide FtsZ formation in the centre of the cell

233
Q

What does MinD do?

A

Forms a sprial structure to localize MinC and it inhibits cell division by oscillating back and forth along the long axis of the growing cell

234
Q

What does MinC do?

A

It attaches to the cytoplasmic membrane

235
Q

What does MinE?

A

This is the oscillating structure that sweeps MinC and D to the sides and leaves a protein concentration center where the divisome will form

236
Q

What is FtsK?

A

It assists in cell separation when cells are pulled apart to make daughter cells and separates chromosomes

237
Q

What is MreB?

A

This is a protein in Bacteria and Archaea that form a simple cytoskeleton since this protein makes patchlike filaments below the cytoplasm membrane

238
Q

What is RodA?

A

This is a protein that defines cell shape, growth, and elongation

239
Q

What happens when RodA and and MreB are inactive?

A

The cell is spherical or coccid

240
Q

What does MreB do for peptidoglycan synthesis?

A

It localizes it to the points on the cytoplasmic membrane for the rod-shaped filaments

241
Q

What is crescentin?

A

This is a protein that dictates curved cell by shaping with MreB

242
Q

What is signal transduction?

A

The interaction of 2 proteins (2 component regulatory system) in response to an external stimulus and the change the cell makes as a result

243
Q

What is the sensor kinase?

A

This is a protein that often contains a histidine which is autophosphorylated when the external stimulus binds and it then transfers the phosphate to the response regulator component this is on the cytoplasmic membrane not the outer membrane

244
Q

What is the reponse regulator component?

A

This is where the phosphate is transferred to and it is often a DNA binding protein and its binding can lead to inhibition or activation of the gene transcription

245
Q

Which activity is faster kinase or phosphatase?

A

Kinase

246
Q

What does a phosphatase do?

A

It resets the molecule by removing the phosphate group

247
Q

How does a biofilm form?

A

The microbes attach to a suface or outer layer that consists of polysaccharide slime

248
Q

How do the bacteria bind to biofilm?

A

Through their filamentous protrusions consisting of a protein extension from a cell known as a pili

249
Q

What is a frimbriae?

A

A shorter pilus

250
Q

What is a conjugative pili?

A

A pilus that facilitates genetic exchange between cells

251
Q

What is the purpose of gas vesicles?

A

It allows the bacteria to be buoyant so it can take in O2 for photosynthesis and it is a form of motion

252
Q

What are endospores?

A

These are pockets of genetic material that do not help with reproduction and they can remain dormant for many years before converting back to a vegetative cell under favourable conditions

253
Q

What is polar bacteria?

A

There is a cell that has a single flagella attached at one or both ends

254
Q

What is liphotrichous bacteria?

A

When there is a cell that has a tuft/group of flagella bound to one end of the cell

255
Q

What is amphitrochous?

A

These are bacteria that have tufts of flagella on both ends of the cell

256
Q

What is peritochous?

A

This is when there are flagella surrounding the cell

257
Q

What happens when a peritochous bacteria “runs”?

A

The flagella rotate CCW

258
Q

What happens when a peritochous bacteria “tumbles”?

A

The flagella spread out and rotate CW

259
Q

What happens when a polar bacteria “runs”?

A

The flagella rotates CCW

260
Q

How does a polar bacteria tumble?

A

It stops reorients and goes in a different direction doesn’t tumble

261
Q

How does a polar bacteria’s motility change when the flagella rotates CW?

A

It is unidirectional so it reverses

262
Q

Does a polar bacteria push or pull?

A

Pull

263
Q

Describe the flagella structure?

A

Hollow, rigid, helical, and complex (encoded by about 50 genes)

264
Q

What is the stator?

A

This part of the flagella is made of Mot proteins it is anchored to the cytoplasmic membrane and peptidoglycan

265
Q

What is the MS and C ring?

A

These are rings that are bound to the cytoplasmic membrane

266
Q

What is the L ring?

A

This is bound to the outer membrane of Gram negative bacteria

267
Q

What is the P ring?

A

This is bound to the peptidoglycan

268
Q

What is the role of the stator?

A

To generate torque by the passing of the H+ through the channel

269
Q

What is the filament?

A

It is the main structure of the flagella that is made of flagellin

270
Q

What is the hook?

A

This is the anchor of the filament to the basal body

271
Q

What is the basal body?

A

The structure complex of the stator and the rings that are bound to the cytoplasmic membrane, peptidoglycan, and outer membrane in some

272
Q

What structure do Gram positive not have?

A

L ring

273
Q

What is the order of the structures being made?

A

1.) MS / C rings
2.) Mot proteins
3.) P ring
4.) L ring
5.) Early hook
6.) Cap
7.) Filament

274
Q

What are some of the differences between archaelum and flagella?

A
  • Archaellum is not hollow
  • Less complex
  • Slower
  • Made from the base not the tip like flagella
  • Driven by ATP hydrolysis not PMF
275
Q

What are 2 types of surface motility?

A

Twitching and gliding

276
Q

What is twitching?

A

This is a form of motility that involves a type IV pilus from the pole of one cell and it pulls the cell forward powered by ATP hydrolysis the motion is like a grappling hook where the pili bind pull the cells forward retract and continue

277
Q

What is gliding?

A

This is a form of motility which unlike swimmin is a smooth continuous motion that often rod shaped cells undergo due to the helical path of the motor that is powered by the PMF and the adhesive proteins

278
Q

What is chemotaxis?

A

This is the process of responding to the environmental stimuli either being attracted to it or repelled from it

279
Q

What happens in response to chemotaxis?

A

There can be more or less tumbles

280
Q

What is the MCP?

A

This is the methyl accepting chemotaxis protein where the stimuli can bind directly or indirectly

281
Q

What is CheW?

A

This is the link between CheA and MCP and helps phosphorylate CheA by hydrolysis of ATP

282
Q

What is CheY?

A

This is the regulatory system that is phosphorylated by CheA

283
Q

What is CheZ?

A

Dephosphorylates CheY

284
Q

What is CheR?

A

Methylates and activates MCP

285
Q

What is CheB?

A

Autophosphorylates and demethylates MCP

286
Q

What happens when the mechanism for chemotaxis is active?

A

The CheY-P interacts with the flagella motor and leads to a tumble

287
Q

What are macronutrients?

A

These are nutrients that are required in large amounts

288
Q

What are micronutrients?

A

These are nutrients that are needed in trace amounts ie., metals

289
Q

What is defined media?

A

When you know the composition

290
Q

What is complex media?

A

Media consists of metabolites it is not defined

291
Q

What is selective media?

A

Media that only allows some cells to grow

292
Q

What is enriched media?

A

Media that is favourable for some cells but counteractive for other cells

293
Q

What is differenital media?

A

Media that contains dye to stain for growth

294
Q

What is binary fission?

A

The division of bacterial cells

295
Q

What is the generation time?

A

The time it takes for the population to double

296
Q

What is the lag phase?

A

The phase between the inocculation and the onset of growth

297
Q

What does a long lag phase mean?

A

Preparing by making enzymes from one environment to a new one that is different

298
Q

What does a short lag phase mean?

A

The environment being introduced are similar

299
Q

What is a stationary phase?

A

The growth can’t occur forever: nutrient is depleting and waste accumulates, growth = death

300
Q

What is the decline phase?

A

When there is some cryptic growth but the death overwhelms the growth of the total number of cells

343 (6 decks)

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