Dr. Leys Study Guide Flashcards
DNA that enters a bacterial cell can be…
- Degraded
- Integrated into the host chromosome
- Integrated into a plasmid
Restriction endonucleases/enzymes
Used by bacteria to degrade foreign DNA
Transformation
The uptake of naked DNA by “competent cells”
Transduction
The transfer of DNA between bacteria through a virus
Conjugation
Transfer of DNA between bacteria through cell to cell contact using sex plius
Mutations in DNA can cause
Antibiotic Resistance
Types of DNA Mutations
Base changes Deletions Insertions Duplications Rearrangements
What type of DNA mutation is least likely to cause antibiotic resistance
Deletions
Different bacteria occupy…
different niches in the oral cavity
Subgingival bacteria are…
Generally proteolitic
Supragingical bacteria are…
Generally Saccrolitic
Factors that promote colonization in the oral activity include
Adherence properties Synergistic bacteria Nutritional substrates Temperature Moisture control
Factors that inhibit colonizaiton in the oral cavity include
Antimicrobial properties of saliva
Mechanical shearing
Antagonistic bacteria
Bacterial species related to perio
More species are associated with periodontitis, while fewer species are associated with periodontal health
Microbial composition in periodontitis
Shifts in microbial composition occur in periodontitis, however no bacterium is found in all patients with periodontitis, and never found in healthy subjects
Tissue destruction that occurs during periodontitis is due to..
Host response
There is a small shift during periodontitis
From gram positive to gram negative
During periodontitis, the complexity of the microbial community…
Increases
There is a slight shift to more __________ uncultivated bacteria in periodontitis
Uncultivated
Microbial diversity __________ in caries
Declines
As caries progresses…
There is a progression of dominant species
Each location in the oral cavity has its own…
Associated microbial composition. However, there is overlap
