(L5) Bacterial Genetics Flashcards
(116 cards)
1
Q
It is the study of how genetic information is transferred,
either from a particular bacterium to its offspring or
between interbreeding lines of bacteria and how that
genetic information is expressed.
A
BACTERIAL GENETICS
2
Q
It is the study of the mechanisms of heritable information
in bacteria, their chromosome, plasmids, transposons,
and phages.
A
BACTERIAL GENETICS
3
Q
Who studied the Differences of morphology and other properties of bacteria were attributed
A
Nageli (1877)
4
Q
Studied the Transformation of bacteria observed
A
Frederick Griffith (1882)
5
Q
Examined at the molecular level by ____________
and his colleagues, who used the process to demonstrate
that DNA was the genetic material of bacteria
A
Oswald Avery (1944)
6
Q
Bacterial conjugation discovered by ______________________ was noted
A
Joshua Lederberg and Edward Tatum (1946)
7
Q
ARRANGE IN ORDER:
- Transformation of bacteria observed by
Frederick Griffith - Bacterial conjugation discovered by Joshua
Lederberg and Edward Tatum was noted - Examined at the molecular level by Oswald Avery and his colleagues, who used the process to demonstrate that DNA was the genetic material of bacteria
- Differences of morphology and other properties of bacteria were attributed by Nageli
A
- Differences of morphology and other properties of
bacteria were attributed by Nageli - Transformation of bacteria observed by
Frederick Griffith - Examined at the molecular level by Oswald Avery
and his colleagues, who used the process to demonstrate
that DNA was the genetic material of bacteria - Bacterial conjugation discovered by Joshua
Lederberg and Edward Tatum was noted
8
Q
Small supplemental circular DNA
molecules of a few hundred or
thousand base pairs in
circumference.
A
PLASMIDS
9
Q
Naturally occurring plasmids
are viruses of _________
A
bacteria
10
Q
Are the small circular, double stranded, DNA molecules
within a cell, physically separated from chromosomal
DNA that can replicate independently. Which are distinct
from chromosomal DNAs
A
PLASMIDS
11
Q
Plasmids are the small circular, double stranded, DNA molecules within a cell, physically separated from ___________ that can replicate independently. Which are distinct from chromosomal DNAs
A
chromosomal DNA
12
Q
2 FUNCTIONS OF PLASMIDS:
A
- Help bacteria to survive stress
2. Make themselves indispensable
13
Q
PLASMIDS HELP BACTERIA TO SURVIVE STRESS:
• Naturally exist in _________, and they also occur in
some eukaryotes.
• Often the genes carried in Plasmids provide bacteria with genetic advantages such as __________
A
Bacterial cell ; Antibiotic resistance
14
Q
PLAMIDS MAKE THEMSELVES INDISPENSABLE:
Bacteria can also transfer plasmids to one another
through a process called _________
A
conjugation
15
Q
Ways to classify Plasmids from general to specific:
A
- Conjugative
- Non-Conjugative
- Incompatibility
16
Q
Bacteria reproduce by sexual conjugation
A
Conjugative Plasmids
17
Q
transfer of genetic material from one bacterial cell to another, either through direct contact or a bridge between the two cells.
A
Conjugative Plasmids
18
Q
Some plasmids contain genes called _________
that facilitate the beginning of conjugation
A
transfer genes
19
Q
Cannot start the conjugation process, and they can only be transferred through sexual conjugation with the help of
__________
A
Non-conjugative; conjugative plasmids
20
Q
In a bacterium, different plasmids can only co- occur if they are compatible with each other. An ____________ will be expelled from the bacterial cell.
A
incompatible plasmid
21
Q
Plasmids are incompatible if they have the (SAME or NOT SAME) reproduction strategy in the cell. This allows the
plasmids to inhabit a certain territory within it without
other plasmids interfering.
A
SAME
22
Q
Contain transfer genes that allow genes to be transferred from one bacteria to another through conjugation. These make up the broad category of conjugative plasmids.
A
Fertility F-Plasmids
23
Q
5 MAIN CLASSES OF PLASMIDS
A
- Fertility F-Plasmids
- Resistance Plasmids
- Virulence Plasmids
- Col Plasmids
- Degradative Plasmids
24
Q
Contain genes that help a bacterial cell defend against
environmental factors such as poisons or antibiotics.
A
Resistance Plasmids
25
Plasmid that turns that bacterium into a pathogen,
Virulence Plasmids
25
Plasmid that turns that bacterium into a pathogen,
Virulence Plasmids
26
Contain genesis that make bacteriocins, which are proteins that kill other bacteria and thus defend the host bacterium.
Col Plasmids
27
Col Plasmids are also known as
Colicins
28
Help the host bacterium to digest compounds that are not
| commonly found in nature. These plasmids contain genes for special enzymes that break down specific compounds.
Degradative Plasmids
29
The DNA of most bacteria is contained in a single circular
| molecule, called the
bacterial chromosome.
30
The chromosome, along with several proteins and RNA
molecules, forms an irregularly shaped structure called
the _________. This sits in the cytoplasm of a bacterial cell.
nucleoid
31
Analogy
BACTERIAL CHROMO:
PLASMIDS: It is circular.
BACTERIAL CHROMO: Linear because of Linear DNA
32
Analogy
BACTERIAL CHROMO: Essential to cell function
being the genetic information carrier have several thousand genes
PLASMIDS:
PLASMIDS: Not essential but provide survival to host bacteria
33
Analogy
BACTERIAL CHROMO:
PLASMIDS: Smaller in size
BACTERIAL CHROMO: Larger in size
34
Analogy
BACTERIAL CHROMO: Have a centromere and two
sister chromatids
PLASMIDS:
PLASMIDS: Have no centromere and sister chromatids
35
Analogy
BACTERIAL CHROMO: Are not used as gene carriers
PLASMIDS:
PLASMIDS: used as gene carriers for alien cell
36
Analogy
BACTERIAL CHROMOSOME:
PLASMIDS: small number of genes
BACTERIAL CHROMOSOME: larger number of genes
37
PROKARYOTE OR EUKARYOTE:
Contains membrane bound nucleus
Eukaryote
38
PROKARYOTE OR EUKARYOTE:
Does not have nucleus
Prokaryote
39
PROKARYOTE OR EUKARYOTE:
DNA is sequestered inside the nucleus
Eukaryote
40
PROKARYOTE OR EUKARYOTE:
Does not have other membrane-bound organelles
Prokaryote
41
PROKARYOTE OR EUKARYOTE:
Present as a DNA-protein complex called nucleoid
Prokaryote
42
PROKARYOTE OR EUKARYOTE:
Have plasmid DNA
Prokaryote
43
PROKARYOTE OR EUKARYOTE:
Replication occurs in cytoplasm
Prokaryote
44
PROKARYOTE OR EUKARYOTE:
Genes (both introns and exons)
Eukaryote
45
INTRON or EXON:
Non-coding regions of an RNA transcript or the DNA
encoding it are eliminated by splicing before translation.
INTRON
46
INTRON or EXON:
Can be separated by intervening sections of DNA that do
not code for protein known as introns
EXON
47
INTRON or EXON:
Coding sections of an RNA transcript or the DNA
encoding it that are translated soon into a protein.
EXON
48
INTRON or EXON:
It is any nucleotide sequence within a gene that is
removed by RNA splicing during maturation of the final
RNA product.
INTRON
49
INTRON or EXON:
Found in the intragenic region, thus the name
INTRON
50
Is all genetic instructions (genes) for development of:
○ Cellular structures
○ Metabolic functions
○ Regulation
Genome
51
THE BASIC UNIT OF HEREDITY
GENES
52
```
GENES: “BASIC UNIT OF HEREDITY”
● It makes up the body’s blueprint
● We have ________ genes in our body
● It is made from _________
● It is organized in ________
```
35,000; DNA strands; structures
53
BINARY FISSION STEPS
1. Parent cell
2. DNA replicates
3. Two daughter cells
4. Cytoplasm divides
54
BINARY FISSION:
the cell elongates with a
septum forming at the middle. The two (2)
chromosomes are also separated in this phase.
Cytoplasm Divides
55
BINARY FISSION:
bacteria uncoils and replicates its chromosome, essentially doubling its content
Parent cell
56
BINARY FISSION:
a new cell wall is formed at
this phase and the cell splits at the center, dividing
the parent cell into two (2) new daughter cells.
Two daughter Cells
57
BINARY FISSION:
bacterium starts to grow larger in preparation for binary fission.
DNA Replicates
58
VARIATIONS OF BACTERIA
1. Spontaneous mutation
2. Transformation
3. Transduction (Plasmids and DNA fragments)
4. Conjugation
5. Transposons
59
Bacteria have circular chromosomes that lacks
| histone protein on the DNA
Circular Chromosome
60
Bacteria have different kinds of gene transfer
| systems.
Bacterial Gene Transfer Systems
61
● Stray pieces of DNA from their environment and make it part of their genome.
● Basically, transformation is where a bacterium takes a piece of DNA floating in its environment and then they make it apart of their own genome
Transformation
62
● Bacterial genes can accidentally get included in
bacteriophage viral DNA
● This is where DNA is accidentally moved from 1
Bacterium to another by a virus.
Transduction
63
● Strains exchange genes through a cytoplasmic bridge
called _____
●_______ is where DNA is transferred between
bacteria through a tube between cells
Conjugation; pillus
64
MAIN PURPOSE OF TRANSFORMATION:
Repair DNA damage
65
WHY IS KNOWING TRANSFORMATION IMPORTANT?
Imagine a harmless bacterium takes up DNA from a toxin
gene, from a pathogenic or diseased causing species of
bacterium. If the receiving cell incorporates the new DNA in its own chromosome, which can happen by a process called __________, then it too may become pathogenic or disease-causing spreading the bacteria in a human's body.
homologous recombination
66
Is the process by which foreign DNA is introduced into a
| cell by a virus or viral vector
Transduction
67
TRANSDUCTION STEPS:
1. Bacteriophage injects DNA
2. Phage enzyme breaks down host DNA
3 & 4. Cell creates phage and host DNA
5 & 6. Transducing phage injects donor DNA to recipient cell
7. Transduced bacterium contains donor DNA due to recombination
68
there is the transfer of portion of DNA from one bacterium to another by bacteriophages
Transduction
69
Again, viruses that infect bacteria in transduction, move
short pieces of chromosomal DNA from one bacterium to
another by _______
accident
70
These viruses that infect bacteria are called ________.
__________ are the pirates of the biological world, they commandeer a cell’s resources and use them to make more bacteriophages.
Bacteriophages
71
It is commonly used as vectors in recombinant DNA
| technology.
Bacteriophage
72
STEPS OF BACTERIOPHAGE ATTACHMENT:
1. Landing
2. Pinning
3. Tail Contraction and Penetration
4. DNA injection
73
______ take over the machinery of the cell to make
phage components. They then destroy, or lyse, the cell,
releasing new phage particles.
Lytic phages (virulent)
74
________ incorporate their nucleic acid into the
chromosome of the host cell and replicate with it as a unit
without destroying the cell. Under certain conditions
lysogenic phages can be induced to follow a lytic cycle.
Lysogenic phages
75
In chronic infection new phage particles are
produced continuously over long periods of time
but without apparent cell killing.
Lysogenic phage (temperate)
76
2 TYPES OF TRANSDUCTION
Specialized Transduction and Generalized Transduction
77
```
Is it mediated by lytic
phages (or virulent phage, a
phage which causes lysis of
host cell death), where the
DNA segment can be
transferred by the virus and
do not incorporate the
segment to the bacterial
chromosome.
```
GENERALIZED TRANSDUCTION
78
```
Is mediated by lysogenic
phages (temperate phage,
your temperate phage
allows phage conversion.;
wherein specific viral DNA
fragments are integrated
into the host bacterial
chromosome.
```
Specialized Transduction
79
Used to insert new genes into bacteria engineered
| plasmid used
Biotechnology
79
Used to insert new genes into bacteria engineered
| plasmid used
Biotechnology
80
This is an engineered plasmid used in biotech
pUC18
81
pUC18 has been genetically engineered to include:
1. gene for antibiotic resistance to Ampicillin (ampR)
| 2. gene and its promoter for the enzyme beta-galactosidase (lacZ)
82
________ is the process by which one bacterium
transfers genetic material to another through direct
contact. During _________, one bacterium serves as
the donor of the genetic material and the other serves
as the recipient. The donor bacterium carries a DNA
sequence called the __________.
conjugation; Fertility F-Factor
83
Example for Conjugation:
Cytoplasmic bridge allows transfer of DNA
Eschirichia coli and Mycobacterium smegmatis
84
Donor cells typically act as donors because they have a a chunk of DNA called your ________
Fertility F-Factor
85
If the F factor is transferred during conjugation, the
receiving cell turns into an _______ that can make its
own pilus and transfer DNA to other cells.
F-plus Donor
86
* A _________ is an enzyme that catalyzes the hydrolytic cleavage of phosphodiester linkages in the DNA backbone, thus degrading the DNA.
* The ______ are one type of nuclease which is a generic term for an enzyme capable of hydrolyzing phosphodiester bonds that link nucleotides.
Dnase
87
mediated by the expression of plasmid genes
E. coli conjugation
88
mediated by genes on the bacterial chromosome
Mycobacterial conjugation
89
* A piece of DNA that moves from one location in genome to another (as seen in the diagram)
* ________ is a class of genetic elements that can jump to different locations within a genome.
Transposons (Jumping Genes)
90
The chunks of DNA “jump” from one place to another within a genome, cutting and pasting themselves or inserting copies of themselves in new spots.
Transposable Elements
91
a bacterium takes up a piece of DNA
| floating in its environment.
Transformation
92
DNA is accidentally moved from one
| bacterium to another by a virus
Transduction
93
DNA Is transferred between bacteria
| through a tube between cells.
Conjugation
94
GENE REGULATION:
Which encode regulatory genes,
are often at the five-prime (5’) end to the start site of
transcription of the gene they regulate
Regulatory Sequence
95
GENE REGULATION:
Is a sequence of DNA needed to turn a gene
on or off
Promoter
96
GENE REGULATION:
Are clusters of genes that share the same
promoter and are transcribed as a single large mRNA that contains multiple structural genes or cistrons
Operons
97
GENE REGULATION:
Substances that act on an operon to inhibit
messenger RNA synthesis
Repressor
98
GENE REGULATION:
Gene involved in controlling the
expression of one or more other genes.
Regulatory Gene
99
POSITIVE CONTROL or NEGATIVE CONTROL:
Protein known as an
activator binds to the DNA
in order for transcription to
take place
POSITIVE CONTROL
100
POSITIVE CONTROL or NEGATIVE CONTROL:
Protein known as a
repressor binds with the
DNA and blocks
transcription
NEGATIVE CONTROL
101
POSITIVE CONTROL or NEGATIVE CONTROL:
Transcription under
negative control
NEGATIVE CONTROL
102
POSITIVE CONTROL or NEGATIVE CONTROL:
Transcription is under
positive control
POSITIVE CONTROL
103
POSITIVE CONTROL or NEGATIVE CONTROL:
Example is Lactose operon which deals with lactose
POSITIVE CONTROL
104
POSITIVE CONTROL or NEGATIVE CONTROL:
Example is Tryp operon that deals with tryptophan
NEGATIVE CONTROL
105
● Raw material of evolution
● Deals with changes in base sequences of DNA
● As well as changes in DNA that affect the genetic
information
● No variation, no evolution
● DNA polymerase
Mutation
106
TYPES OF MUTATION
1. Substitution
2. Insertion
3. Deletion
4. Inversion
107
○ Occurs when specific bases (A, T, C, or G) in a gene
| are swapped for different ones
Substitution
108
is the addition of one or more nucleotide
| base pairs into a DNA sequence
Insertion
109
Involving the loss of genetic materia
Deletion
110
This where a chromosome rearrangement in which a
segment of a chromosome is reversed end to end (it
is inverted)
Inversion
111
Example of Inversion
Opitz - Kaveggia syndrome
112
Example of Substitution
Sickle-Cell anemia
113
Example of Insertion
One form of beta-thalassemia
114
Example of Deletion
Cystic Fibrosis
