Bacteriology 1 2 Flashcards
Compare prokaryote to eukaryote
No nucleus vs nucleus. Circular DNA (supercoiled) vs linear chromosomes. No membrane bound organelles vs yes and other membranes. 70S vs 80S ribosomes. Peptidoglycan cell wall vs not.
Bacterial structures to know
Nucleoid, ribosomes, plasma membrane, cell wall, capsule, pili, flagella
Function of pilus
Pili bring bacteria together for exchange plasmids, but plasmids are not transferred through the pili rather through a pore.
Glycocalyx
Glycocalyx and slime layer (Sugary coating), or glycocalyx and capsule (sticky and protects from immune system)
Why do we need to know the structures?
Targets for antibiotics esp b/c they are different from ours
How can we differentiate b/w bacteria types?
Microscopic and colony features (shape, grouping, mobility, gram stain), Metabolism and oxygen requirements, Growth Environment (differential media etc), Virulence factors
How do bacteria cause disease? Steps
Pathogenic organism, reservoir, acquisition, adhesion, local multiplication, invasion, evade immune system, damage
Review on classification of organisms
Kingdom (apparently 6), Phylum, Class, Order, Family, Genus, Species
6 kingdoms
Eubacteria (normal bacteria), archaebacteria, protista, fungi, plantae, animalia
How to name bacteria
Genus and species
Stain options
Gram stain (no good for mycobacteria): fix, crystal violet, iodine, decolourize, counterstain. Acid fast stain (for mycobacteria - show red): heat/phenol, dye, rinse with acid alcohol (hence acid fast)
Gram positive vs gram negative
Positive: purple-blue; Thick peptidoglycan; Teichoic acids and lipoteichoic acids; No outer membrane. Negative: red; Thin peptidoglycan; Space surrounding the peptidoglycan layer; Outer membrane (protection, porins); Lipopolysaccharides in the outer membrane
