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Flashcards in bacteria basics Deck (67):
1

acute phase cytokines

IL-1
IL-6
TNFα

2

hair-like structures that mediate adherence of bacteria to surfaces (respiratory, GI tract)

fimbriae

3

forms attachment between 2 bacteria during conjugation

pilus

4

pilus allows transfer of DNA (plasmids = resistance, virulence factors = toxins) from one bacteria to another

conjugation

5

longer than fimbriae and pilus
provide whip-like motility

flagella

6

gelatinous polysaccharide coat of bacteria
adds in attachment to foreign material (indwelling catheter, teeth)

glycocalyx

7

if organized glycocalyx (polysaccharide coat) and firmly adherant to bacteria (sugar coat)

capsule

8

if loosely adherant and less organized glcyocalyx (polysaccharide coat)
produced by bacteria
shields from antibiotics, hard to remove

slime/biofilm

9

protects bacteria from phagocytosis
allows for time to evade immune system and divide

capsule (type of virulence factor)

10

test to detect encapsulated bacteria:
anti-capsular serum added to bacteria
positive: capsule swells under microscope

quellung reaction

11

encapuslated bacteria

SHiN
**Streptococcus pneumoniae
**Haemophilus
influenza type B
**Neisseria meningitidis

12

most vulnerable population to encapsulated bacteria infection

splenectomy patient
vaccinate against polysaccharide capsule (antigen):
**Streptococcus pneumoniae
**Haemophilus
influenza type B
**Neisseria meningitidis

13

yeast with capsule

cryptococcus neoformans

14

ribosomes

location of protein synthesis
2 subunits combine to translate mRNA

15

prokaryote (bacterial) ribosomes

70S (50S + 30S)

16

eukaryote (human) ribosomes

80S (60S + 40S)

17

genetic material separate from chromosomal DNA and
replicate separately
genes for: antibiotic resistance, enzymes, toxin production
transferred during conjugation

plasmids

18

mechanisms of genetic change in bacteria

conjugation via pili and plasmids
transformation
transposition
transduction

19

DNA released from lysed cell and then taken up by a living bacterium
DNA fragments incorporated into chromosomal DNA→recombinant bacteria

transformation

20

what bacteria can acquire genetic material via transformation

SHiN
**Streptococcus pneumoniae
**Haemophilus
influenza type B
**Neisseria meningitidis

21

small segments of DNA that can self-exise and relocate
transfer from chromosome to plasmid (allow for AR, spread to another bacteria via conjugation) and vice versa, chromosome to chromosome
may carry antibiotic resistance, VFs

transposons

22

bacteriophage (phage = virus that infects bacteria) attaches to bacterium and injects its DNA
phage DNA and proteins are repackaged in viral capsids -
some bacterial DNA also be in the viral capsid
new phage injects viral and bacterial DNA into next bacterium
bacterial DNA of virus + host can combine

transduction

23

sterols in plasma membrane
NO cell wall

mycoplasma (bacteria)

24

cell wall:
mycolic acid
high lipid content (resistant to gram staining)

mycobacteria

25

dormant form of bacteria until hospitable environment is available, then replicate again
resist: dessication, heat, cold, disinfectants, lack of nutrients

spores

26

bacteria that don't gram stain well

These Microbes May Lack Real Color:
Treponema (G- corkscrew, too small to visualize)
Mycobacteria (high lipid content in cell wall)
Mycoplasma (no cell wall)
Legionella pneumophila (branched fatty acids in cell walls, intracellular)
Rickettsia (intracellular)
Chlamydia (intracellular)

27

Giemsa stain

Honestly, Certain Bugs Really Try my Patience
Histoplasma
Chlamydia
Borrelia
Rickettsiae
Trypanosomes
my
Plasmodium

28

periodic acid schiff (PAS) stain

PASs the sugar (stains gycogen + mucopolysaccharides)
Tropheryma whipplei (Whipple's disease)

29

ziehl-neelsen stain

stain acid fast organisms:
mycobacterium tuberculosis

30

india ink stain

encapsualated yeast: cryptococcus neoformans

31

silver stain

fungi: pneumocystis jirovecii
legionella

32

provides rigid support to bacterial cell and protects against osmotic pressure differences

peptidoglycan layer of cell wall

33

spore-forming bacteria when nutrients limited or environment is inhospitable

G+ rods: bacillus, clostridium
others: coxiella burnetti

34

bacteria has to be in aerobic environment to grow and produce energy

obligate aerobe

35

obligate aneorobe bacteria

lack catalase and superoxide dismutase:
G+: clostridium tetani, actinomyces
G- rod: bacteroides

36

antibiotics for aneorbes

metronidazole
clindamycin

37

causes of neonatal sepsis

GBS
E coli (G-)
listeria monocytogenes (G+)

38

organisms most commonly implicated in subacute endocarditis

viridans group streptococci (most common cause of subacute infective endocarditis)
enterococci
s. bovis
coagulase negative staph (s. epidermidis)
HACEK organisms

39

most common cause of meningitis

s. pneumoniae

40

most common cause of ostoemyelitis

s. aureus

41

most common bacterial cause of otitis media in children

s. pneumoniae

42

cellulitis

s. aureus
s. pyogenes

43

associated with reactive arthritis (Reiter's syndrome)

G- diarrhea bugs:
shigella
salmonella
campylobacter jejuni
yersinia
others:
chlamydia trachamotis

44

infection associated with animal urine

leptospira (spirochete)
hantavirus (rodent urine)

45

diarrhea after raw eggs or raw chicken

G-:
campylobacter
salmonella

46

rice water stools

G-:
vibrio cholerae
ETEC

47

diarrhea from household pet

G- rods:
yersinia enterocolitica
salmonella (reptiles, pet turtles)

48

blood diarrhea after eating undercooked hamburger meat

EHEC

49

diarrhea + RLQ pain like appendicitis

yersinia

50

pregnant women should avoid unpasteurized milk due to these bacteria

listeria
brucella species
coxiella burnetti

51

most common bacterial cause of cervicitis

chlamydia trachomatis

52

antibiotic put on eyes after baby is born birth

gonorrhea conjunctivitis
doesn't treat chlamydia conjunctivitis (use oral azithromycin or erythromycin)

53

3 main causes of atypical pneumonia ("atypical")

legionella pneumophila
chlamydophila pneumoniae
mycoplasma pneumoniae

54

treatment for atypical pneumonia ("walking")

empiric treatment (don't look for bug) since antibiotic covers all:
azithromycin
doxycycline
flouroquinolones

55

bacteria that are non-staining + culture poorly

gardernella vaginalis: bacteria vaginosis
ricketssiae: Giemsa
Ehrlichia chaffeensis: human monocytic ehrlichiosis
Anaplasma phagocytophilum: human granulocytic anaplasmosis
Coxiella burnetti: Q fever
chlamydia species
mycoplasma pneumoniae

56

if low glucose in CSF fluid consider

bacterial meningitis
tuberculosis meningitis

57

obligate intracellular bacteria

rickettsia
coxiella
chlamydia

58

catalase-positive organisms

S. aureus
E. coli
pseudomonas
klebsiella
aspergillus
salmonella
↑ catalase + infections in chronic granulomatous disease (phagocytes lack free radicals to kill due to no NADPH oxidase)

59

mycobacteria that causes TB-like symptoms in COPD patients

mycobacterium kansasii

60

mycobacteria that causes cervical lymphadenitis in children

mycobacteria scrofulaceum

61

mycobacteria that causes disseminated disease in AIDs patients

MAI or MAC
mycobacteria avium intracellulare
mycobacteria avium complex

62

mycobacteria that causes hand infection in aquarium

mycobacteria marinum

63

obligate aerobe bacteria

Nagging Pests Must Breathe
Nocardia
Pseudomonas aeruginosa
Mycobacterium tuberculosis
Bacillus

64

characteristics of enterobacteriaceae in colonic flora

G-, facultative anaerobic bacteria (don't need O2)
ferment sugar into lactic acid
if excess in colon: can cause lactic acidosis due to absorption

65

function of MacConkey agar

isolates G- bacteria (crystal violet + bile salts inhibits growth of G+)
distinguish lactose fermenters (pink) from non-lactose fermenters (white)

66

cell wall inhibitor effective against pseudomonas

3rd or 4th gen cephalosporins
carboxypenicllin (like ticarcillin)
aztreonam
carbapenems

67

produce urease: hydrolyzes urea → ammonia →↑ pH of urine (more alkaline) → struvite stones (magnesium ammonium phosphate): "staghorn calculus"

proteus mirabilis
klebsiella

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