Microbes and Bacterology Flashcards
What makes an infectious organism harder to target
the more cellular structures we have in common
Why are viruses not shown on the tree of common ancestors?
they require a host to replicate
In terms of size how big is a prokaryote compared to the smallest eukaryotic cells?
it’s about half the size. 5μm. where eukaryote is 10μm
What shape are cocci?
what shape are staphylococci?
bunches like grapes
what shape are streptococci?
lines like beads on a string
what shape are bacilli?
What shape are vibrio
What shape are fusiform bacilli?
long, slender rod
what shape are spirilla?
curving rod, NOT a corkscrew
What shape are spirochete?
helical/corkscrew-shaped, very slender rod
A typical bacillus is 3μm long, how small is the small pox virus?
.3x.2x.1μm. polio virus is .003μm
How can we use a bacteriaphage in the lab?
to target bacteria and to transfer genes b/w them
What are the only layers in a non-enveloped virus?
nucleic acid and capsid (made of capsomere)
Give an example of a non enveloped virus and why is it more stable than an enveloped virus?
polio, b/c it’s so simple, it is easier to transfer from person to person. FYI polio can be transmitted in water
How does a non-enveloped virus attach to cells?
structures in the capsid
why are enveloped viruses easier to sterilize/disable compared to non-enveloped viruses?
the lipid bilayer from is usually derived from the host. The lipid bilayer is sensitive to desiccation (drying out), heat, alcohol, detergents. typically must transfer from host to host.
what is found on the outside of enveloped viruses?
glycoproteins and a lipid bilayer
give an example of an enveloped virus
HIV– bodily fluid transfer
what form is a helical nucleocapsid typically found?
how does a virus replicate?
inside a host cell. viral surface binds to proteins on host cell and are engulfed.. cells know they are infected and signal the immune system to kill them
what is the whole strategy for survival of enveloped proteins based around?
glycoproteins being the receptors for the host cells.
the genome components of viruses can be targeted by the immune system. What is unique to viruses along the lines of nucleic acids?
Viruses have double stranded RNA- this is a good target for the innate immune system.
What are some of the roles of “normal flora” or “microbiota”?
- Digest food
- synthesize vitamins
- compete against pathogens
- immune tolerance for normal bacteria
What is used as the gold standard to identify bacteria to the species level?
16s rRNA sequencing on the SSU
TLR 5 target: