Bacterial Properties Flashcards
What are bacteria?
Small unicellular prokaryotes
Describe Bacterial DNA:
Haploid w/circular DNA chromosome
Do bacteria have a cell wall?
Yes
What does Gram stain bind to?
Peptidoglycan in cell walls
What are beneficial bacteria called?
Commensal
Name 5 Gram negative bacteria and the diseases they cause:
Escherichia Coli (EPEC -diarrhea, EHEC -dysentry)
Salmonella (typhimurium - food poisoning)
Shigella (Dysentry)
Vibrio cholerae (Cholera)
Neisseria (menningitidus - meningitis. gonorrhoeae - gonorrhea)
Name 3 Gram positive bacteria and the diseases they cause:
Staphylococcus aureus (pneumonia, endocarditis)
Streptococcus pneumoniae (pneumonia, meningitis, otitis media)
Streptococcus pyogenes (tonsilitis, necrotising fasciitis)
Name 2 mycobacteria and the diseases they cause:
Mycobacterium tuberculosis (TB)
Mycobacterium leprae (Leprosy)
What are the 2 locations a bacterial pathogen can replicate in a host?
Extracellular: S. aureus/Strep, neisseria
Intracellular: Listeria, Shigella, Salmonella, Mycobacteria
How do Salmonella and mycobacteria survive inside cells?
Present lysosome fusion
What do some bacteria use to inject virulence proteins into cells?
Injectisome; translocase complex creates pore in host cell
What is vertical transmission?
Binary fission: bacterial replication resulting in inheritance of identical CircDNA
What are the three methods of horizontal gene transfer?
Transformation
Conjugation
Transduction
What is transformation?
[horizontal transfer]
DNA uptake proteins incorperate DNA released from other sources into genome
What is Conjuative transfer?
Mating bridge forms and plasmid replicated and transferred
What is Phage transduction?
Bacteriophages infect bacteria and assemble new particles using parts of bacterial DNA, which can then be transferred to other cells
What is the name given to regions of DNA that make a bacteria pathenogenic?
Pathogenicity island
What are the three bacterial shapes?
Coccus: Spherical
Bacillus: Cuboidal
Spirilli: Long and spiral shaped
Why do Gram-negative bacteria resist staining?
Thin layer of peptidoglycan, so lose stain
