Chapter 08 - Bacterial Genetics and Biotechnology Flashcards
Genomes
Contains the genetic material (genes) necessary to produce a functional molecule, usually a polypeptide, i.e., gives the organism its traits
Includes all types of DNA found in a cell, which includes all types of DNA found in the cell
Do all cells have chromosomes?
All cells have chromosomes with million of base pairs. Some also have plasmids.
> Bacteria usually have single circular chromosome
Eukaryotes cells usually have multiple linear chromosomes.
Plasmid
Smaller pieces of circular, double stranded DNA independent of the chromosome
Central Dogma of Biology
All living organisms perform DNA replication, transcription, and translation. Which as a whole is the flow of genetic information from one cell to another
Name some characteristics of genomes can be used to identify microbes
> Sequence of bases
Presence of plasmids
Size
Replication
Copying of genetic information during cell division so each daughter cell has the information
Transcription
The information in DNA is used to make RNA
The process of expressing the information begins
Translation
The RNA is used to make polypeptides
Mutate or Mutation
A change in DNA sequence and as these changes accumulate over time, different strains of a species or different species evolve
Horizontal Gene Transfer
To gain or receive genetic material from other cells
A mechanism through which many antibiotic resistance genes are spread
Basic Concepts of DNA Replication
DNA replication occurs by using each of the strands of doubles stranded DNA (dsDNA) as templates to make new strands of DNA
>Parent (template) strands are separated
>DNA polymerase “reads” the template and makes a new strand of DNA that is complementary to the parent via Base pairing
>The process continues until the chromosome has been copied
Why are antibiotic used to target bacterial replication?
Antibiotic target bacterial replication because bacteria have different proteins involved in DNA replication than eukaryotic cells, these are good targets for antibiotics. [TB 8.2]
RNA polymerase function
Its purpose is to recognizes promoters of genes, and makes an RNA copy of the DNA via base paring . and ends when it reaches a terminator region
What happens once RNA has been produce and transcription comes to an end?
The DNA template goes back to a double strand molecule and the produced RNA detach from the DNA strand.
In cells RNA usually exist in what form?
A single strand molecule, although some viruses are double stranded RNA
What structure preforms protein synthesis?
Ribosomes are imperative to protein synthesis (translation)
When does translation begins?
When a ribosome recognizes a ribosome binding site and a start codon from which point RNA is read in groups of three bases…
When does translation ends?
When a ribosome recognizes stop codon…
What is a codon?
A group of three bases that instructs the ribosome which amino acid to add
Why are antibiotic used to target bacterial translation?
Bacteria have different ribosomes than eukaryotes, they are good targets for antibiotics [TB 8.3]
Gene regulation is regulated. TRUE or FALSE
Transcription, translation, and all protein activity must be regulated.
Unnecessary production or activity can waste energy and resources.
Most genes are regulated in response to environmental conditions
>Changes in metabolism based off nutrient levels
>Temperature, pH, osmolarity, etc
>Stress
Regulatory Proteins
Bind to gene promoters to increase (induction) or decrease (repression) transcription or translation
Virulence Proteins
Pathogens express these proteins when they encounter certain conditions to increase their effectiveness
How do microbes sense the external environment?
Sensing external conditions using proteins in the membrane, which determine the proteins activity and gene expression
