Week 3 - Microbiology Bacterial Structure Flashcards
What is a microbe?
Can be:
Bacteria (prokaryotic)
Protozoa (eukaryotic)
Fugi (eukaryotic)
Virus (neither pro or eukaryotic)
Eukaryotic vs Prokaryotic:
Chromosome Chromosome location Nucleolus Extrachromosomal DNA Site of Cellular Respiration Ribosomes Locomotion Pili
Single Circular vs Paired Linear
Nucleoid (no membrane) vs Nucleus (membrane present)
Absent vs Present
Plasmid vs Mitochondria and Chloroplast
30S & 50S/70S vs 40S & 60S/80S in cytoplasm (70S in organelles)
Rotating flagella and gliding vs Undulatin gflagella and cilia, and also amoeboid movement
Sex or attachement pili vs Absent
Bacterial Structure
Two basic shapes:
Rods and Cocci
Other shapes include:
spirochetes (flexible)
spirillum (rigid)
diplococcidiplobacilli
What are bacterial rods?
Rod shaped bacteria
Bacillus
or 2 = diplobacilli
or chains = streptobacilli
or palisades - X, V, or Y figures
What are bacterial cocci?
Circular bacteria
Cocci
or 2 diplococci
or chains, clumps, tetrads, cubical
What are spirochete?
Flexible
Undulating corkscrew shape
What are Spirillium?
RIGID
corkscrew shape
Diplobacilli?
Two rod shaped bacteria
Streptobacilli?
A chain of rod-shape bacteria
Palisades
X, V, or Y shaped bacilli
Cocci
Circular bacteria
Spirochete
Flexible corkscrew bacteria
Spirillum?
Rigid corkscrew bacteria
What are inner workings of bacterial structure?
Chromosome (nucleoid)
Mesosome
Plasmid DNA
Ribosomes and Granules
Mesosome
Chromosomal DNA attached to the bacterial membrane invaginated at the site of bactierial division
Plasmid DNA*
Self replicated unit of DNA distinct from chromosome
Much smaller than chromosome but can contain bacterial resistance genes*
*Give pathogenic attributes or antibiotic resistance to bacteria.. and are passed an as the bacteria divide and grow
Some are mobile* from one bacteria to another… also some can change species..
Flagella
Flagella
Used in bacteria for locomotion
Composed of flagellin
Different arrangements
What are different arrangements of flagella?
Monotrichous (vibrio cholerae)
Lophotrichous (bartonella bacilliformis)
Amphitrichous (spirillum serpens)
Peritrichous (escherichia coli)
Cell envelope
…
Bacterial Chromosome
Only one.. tightly packed
Where are bacterial resistance genes found? *
In the plasmid DNA
Ribosomes
No ER but do have ribosomes - protein synthesis and replication
Whatever is external on bacteria is highly antigenic
we make antiodies to kill bacteria
Flagellar Motor
The ability of some bacteria to move with prescence of flagella helps to figure out which antibiotic to use to treat…
Gram pos - 2 rings
Gram neg - 4 rings