LAB 3 Flashcards
MICROBIOTA
bacteria growing on and in our bodies.
bacteria can be pathogenic, mutualistic, commensal
What is the best way to isolate individual cells?
Streaking them onto an agar plate so that an individual cell can form a colony.
ASEPTIC/STERILE TECHNIQUE
1) STERILE
2) REDUCE EXPOSURE TIME
3) WORK IN A LOW RESISDENT POPULATION AREA OF BACTERIA.
prevent environmental bacteria to contaminate work. REDUCES CONTAMINATION.
1) wash hands before and after handling microorganisms
- Flame items using Bunsen burner
- Glassware+ medium is sterilized using high temp and pressure using autoclave.
ZONE OF INHIBIOTION
area where antibiotic sensitive bact. are unable to grow.
NO ZONE OF INHIBITION
Antibiotic resistant bacteria
ANTIBIOTICS
Prevent bacterial and fungal growth.
16s ribosome sequence
rRNA sequencing or entire genome sequencing to determine diversity of microbiota.
ANITBIOTICS FUNTIONS
1) block cell wall formation or damage it’s integrity
2) block protein synthesis
3) stop DNA replication or transcription.
ANTIBIOTIC RESISTANCE
bacterial ability to actively resist antibiotic function.
TETRACYLINE
acts against UTI, STI to plague.
prevents bacterial protein synthesis.
PENICILLIN
treats Gram-positive bacteria
-prevents crosslinking of bacterial cell wall
CHLORAMPHENICOL
only used for pink eye in North America due to widespread antibiotic resistance.
- more widely used in developing countries.
- inhibits bacterial protein synthesis
How is Antibiotic Resistance spread?
1) Mutation of bacterium’s genes
2) Horizontal transfer
1) one or two small changes in organism that makes it antibiotic resistant.
2) one organism passes genes for antibiotic resistance to the other usually in the form of plasmids(small, circular DNA)
How is antibiotic resistance achieved?
1) modify the antibiotic via degradation or alteration.
2) block influx and cause efflux of antibiotic.
3) “global adaption”- alteration in a major component in cells that prevents antibiotic action.
- Makes cells less viable, overall, in the absence of antibiotic.
GROWTH PROMOTERS
used as additives
-preventative medicine to reduce disease in high density feedlots (livestock)
