Types of bacteria Flashcards
(32 cards)
examples of acid fast bacteria
mycobacterium genus + tuberculosis
cell wall of acid fast bacteria
- contain high amount of glycolipids
- especially mycolic acids
reservoir of actinomyces
natural bacteria of the oral cavity and intestines, skin and pulmonary infection
characteristics of rickettsiae
- small and pleomorphic bacteria 0.3x1-2um
- similar to gram - bacteria
- stain poorly with gram- staining
- no flagella
growth of rickettsiae
- only inside of eukaryotic cells
- obligate intracellular parasites
cell wall of rickettsiae
- typical gram- cell wall
- peptidoglycan layer + LPS
- peptidoglycan is minimal
- LPS has only weak endotoxin activity
staining method of rickettsiae
- giemsa or gimenez stains
energy of rickettsiae
- produce ATP by tricarboxylic acid cycle
- energy parasites -> depend on ATP produced by host cell
- rickettsia prowazekii has parasitic enzyme (ATP/ADP translocase) facilitates transfer of ATP from host cell to bacteria
chlamydiae are
- pleomorphic bacteria
forms of chlamydiae
metabolically inactive
and active
metabolically inactive form
- infectious form
- elementary body
- 0,3-0,4um
metabolically active form
- non-infectious forms
- 0,8-1um
- reticular body
cell wall of chlamydiae
- double layer outer membrane
- LPS and major outer membrane protein MOMP
- week LPS endotoxin activity
- cysteine rich proteins provide stability in elementary bodies
energy parasites
- use host cell ATP for their energy requirements
- some depend on specific amino acids
- obligate intracellular parasites
life cycle of chlamydiae
- initiated by attachment of EBs to microvilli of susceptible cells → active penetration into host cell
- bacteria remain within endosomes → replicative cycle
- 6-8 hours after entering cell → larger active RBs
- RBs replicate by binary fission → inclusion visible under the microscope
- 18-24 hours → RBs begin reorga into smaller EBs
- 48-72 hours → ruptures and releases infectious bacteria
- need ATP from the host
mycoplasma pneumoniae
- pleomorphic
- smallest free living bacteria
size of mycoplasma p.
- 0,2-0,3 um coccoid forms
- 0.1-0,2 width in rods
- 1-2 um long in rods
mycoplasma cell membrane
- no cell wall
- have sterols in cell membrane
- resistent to penicillin, cephalosporins, vancomycin and other antibiotics with synthesis of cell wall
reproduction and growth of mycoplasma
- divide by binary fission
- grow on artificial cell free medium
pathogenic fungi classfication
into 2 phyla
- zygomycota
- dikaryomycota
zygomycota
- produce zygotes during their sexual reproduction
dikaryomycota
- dikaryotic life cycle includes extended dikaryotic phase after sexual conjugation
- divided into 2 subphyla
- ascomycotina
- basidiomycotina
ascomycotina
- reproduction through fusion of 2 compatible nuclei to form diploid nucleus
- meiosis to yield haploid progeny
- process occurs with sac called ascus
- resultant spores → basidiospores
basidiomycotina
- reproduction in sac
basidium and basidiospore
