Bacteriology - Exam 2 Flashcards
bacteria basic characteristics
single cell, prokaryotic, no nucleus, binary fission, 70s ribosomal unit, classified by 16s
shapes for: cocci, bacillus, helical, curved, staph, strep
round, rod, spiral, coma, grape cluster, chain
gram positive bacteria
thick, lipoteichoic acid (antigenicity), stain blue
gram negative bacteria
thin, LPS (virulence), stain pink
mycobacteria contributes to
virulence
endotoxin
only gram negative, Lipid A component & polysaccharide component
Lipid A component of endotoxin contributes to
activation of immune system, harmful effects on host
polysaccharide component of endotoxin contributes to
antigenicity
acid fast positive stains
pink (mycolic acid)
acid fast negative stains
blue
monotrichous flagella
one end
amphitrichous flagella
both ends
lophotrichous flagella
multiple from one end
peritrichous flagella
all sides
endoflagella
from within, spirochetes
pili/fimbriae used for
adherence, antigenicity
K88
pig
K99
cow
capsule function
stick cells together, food reserve, protection, evade phagocytosis
endospore characteristics
gram positive, resistant, live even through bad conditions
examples of endospores
clostridium, bacillus
O2 required in
aerobic, microaerophilic, capnophilic
O2 utilized in
facultative anaerobes
O2 neither required NOR utilized in
obligate anaerobes or aerotolerant anaerobes
pathogen has the potential to
cause disease
7 host characteristics
breed, age, sex, genotype, immunity, physiology, damage
9 pathogen characteristics
type, genotype, survival, virulence, route, tropism, dose, resistance, vector
7 environment characteristics
housing, space, ventilation, hygiene, nutrition, disease control, survival
infection definition
invasion/multiplication in host/population
disease definition
infection causes damage to vital functions
5 examples of portals of entry
skin, mucous membranes, respiratory tract, GI tract, urogenital tract
exotoxin characteristics
proteins released to outside to specific target cells
endotoxin characteristics
gram negative, induce inflammation, heat stable
superantigen characteristics
made by viruses/mycoplasma/bacteria to bind to MHC II on antigen presenting cells & T helper cells to release cytokines
biofilm, quorum sensing, fimbrae, flagella, capsule increase
virulence (can carry genes for antibiotic resistance, movement, protection, etc.)
biofilm example
dental plaque
how does quorum sensing work
certain population reached -> change behavior -> ambush immune system
plasmids
small, circular DNA
examples of plasmids
tetanus & staph (superantigens)
bacteriophages
virus that attack bacteria
examples of bacteriophages
diphtheria, shiga, botulinum
virulence is the degree of
pathogenicity (+/- severity)
virulence transferred by conjugation
transfer genetic material through direct contact through pilus
virulence transferred by transformation
exogenous genetic material taken in
virulence transferred by transduction
DNA transferred between a bacteria & virus
obligate pathogen numbers, predisposition, virulence, disease type
numbers don’t matter, doesn’t need to be predisposed, very virulent, causes distinct disease
primary pathogen disease type
distinct
opportunity pathogen disease type
nonspecific
nonpathogen numbers, predisposition, virulence, disease type
lots of numbers, does need to be predisposed, virulence doesn’t matter, causes nonspecific disease
obligate intracellular pathogen needs
host to replicate
example of obligate intracellular pathogen
Rickettsia, chlamydia
facultative intracellular pathogen can survive
intra or extracellularly
example of facultative intracellular pathogen
mycobacteria, rhodococcus
6 steps pathogen takes to work
entry, evade defenses, colonize, multiply, cause damage, transmit to other hosts (infection)
BSL
biosafety level, higher the number = higher the risk, 4 levels
examples of gram positive bacteria
Strep pyogens, Staph aureus
examples of gram negative bacteria
pasteurella multocida
culture media types
broth, agar, PEA (gram positive), MacConkey (gram negative), Hektoen Enteric Agar (salmonella)
PCR function
polymerase chain reaction; detects specific DNA using amplification and oligonucleotide primers, DNTP, taq polymerase, & target DNA
examples of cell mediated specific immune responses
TB reaction, interferon gamma test
how is agglutination used & why
screen for presence of antibodies by antigen being naturally present
secondary humoral immune response will
produce more antibodies second time exposed
antibody titer
higher antibody response = higher the titer
11 ways to limit microbial growth
refrigeration, freezing, boiling, pasteurization, acidification, increase osmotic pressure (salt/sugar), O2 removal, drying, gamma irradiation, hydrostatic pressure, chemical additives
8 methods of sterilization
moist heat (autoclave), dry heat, incineration, alcohol flame, gamma irradiation, UV light, membrane filtration, chemical
antimicrobial function
destroy microbes, prevent multiplication/growth, natural, synthetic, or semisynthetic
antibiotics function
inhibit/kill other microorganisms at lowest drug concentration possible
natural antimicrobials
produced by bacteria/fungus
examples of natural antimicrobials
tetracycline, streptomycin, penicillin
synthetic antimicrobials
designed in lab
examples of synthetic antimicrobials
sulfonamide, enrofloxacin, marbofloxacin
examples semisynthetic antimicrobials
ampicillin, amikacin
example of a macrolide
erythromycin
example of beta lactam
penicillin
example of aminoglycoside
gentamycin
example of tetracycline
HCl
cell wall synthesis inhibitors
beta lactam (penicillin & ampicillin) cephalosporins (carbapenem & monobactam)
30s protein synthesis inhibitors
aminoglycosides (spectino, strepto, & gentamicin, amikacin)
tetracyclines (oxytetra, chlorte, nitrofurans)
50s protein synthesis inhibitors
macrolides (erythro & azithromycin)
lincosamides (clindamycin)
chloramphenicol
DNA synthesis inhibitors
mutations in DNA gyrase
Quinolones (nalidixic acid, Cipro & enrofloxacin, novobiocin)
metronidazole
RNA synthesis inhibitor: Rifampin
inhibits RNA polymerase (transcription), active against mycobacterium
RNA synthesis inhibitor: Mupirocin
inhibit tRNA synthetase (translation)
folic acid synthesis inhibitors
competitive, uses dihydrofolate reductase
sulfonamides & trimethroprim
4 types of broad spectrum antibiotics
tetracyclines, chloramphenicol, fluoroquinolones, cephalosporins
bactericidal drugs
kills & reduces number
bacteriostatic drugs
arrest growth & replication, helps immune system out
AST 2 methods
“antimicrobial susceptibility testing”
disk diffusion/Kirby Bauer & broth dilution
MIC
“minimum inhibitory concentration”
minimum amount drug needed to work
SIR
susceptible (success)
intermediate (uncertain)
resistant (failure)
innate resistance
preexisting
acquired resistance
mutation/horizontal gene transfer
opportunistic pathogens don’t
cause disease in a healthy host
true pathogens have genes for
virulence (adherence, invasion, evasion)
nosocomial infections
hospital acquired i.e.: MRSA, S aureus, clostridium difficile
mastitis mainly caused by
Staph aureus, Strep pyogens, & Strep agalactiae/dysgalactiae
dog dermatitis mainly caused by
Staph pseudintermedius
greasy pig disease mainly caused by
Staph hyicus
food poisoning mainly caused by
enterotoxin A-E
strangles in horses mainly caused by
Strep equi subsp equi
Bacillus anthracis
gram positive, endospores, exotoxins, capsules, dormant in soil, edema (neutrophil), lethal (zinc)
diamond skin disease/swine erysipelas caused by
erysipelothrix rhusiopathiae
caseous lymphadenitis (goat) caused by
corynebacterium pseudotuberculosis
pyogranulomatous osteomyelitis (lumpy jaw, cows) caused by
actinomyces bovis
mycobacterium tb complex
acid fast positive, facultative intracellular, tb in humans & cows
Johne’s disease in cows caused by
M. avium subsp paratuberculosis
listeria monocytogenes characteristics
food borne, actin filaments, facultative intracellular
listeria monocytogenes causes
septicemia, abortion, meningoencephalitis in cows/goats
tetanus/lock jaw caused by
clostridium tetani
flaccid paralysis in horses caused by
clostridium botulinum
gram negative bacteria enterobacteriaceae found in
H2O, soil, GI tract
examples of enterobacteriaceae
E. coli, klebsiella, enterobacter
E. coli causes
neonatal colisepticemia (calves) edema disease (piglets) hemorrhagic enteritis (humans) hemolytic uremic syndrome & kidney failure
salmonella causes
gastroenteritis & systemic diseases
salmonella dublin, typhi, enteritidis
cows, humans, chicken
what causes fibronecrotic pneumonia in pigs
actinobacillus
what causes shipping fever pneumonia in cattle
pasteurella multocida & mannheimmia hemolytica
what does brucellosis do
affects reproductive system, use macrophages, zoonotic through raw milk
4 species of Brucellosis
abortus, melitensis, suis, canis
what causes kennel cough in dogs & atrophic rhinitis in swine
bordetella bronchiseptica
what does leptospirosis do
lives in kidney (yellow) tubules, zoonotic via urine, spirochete
lyme disease caused by
borrelia burgdorferi
mycoplasma characteristics
no cell wall/peptidoglycan/staining, self replication, pneumonia in humans, bovis- pneumonia & joint arthritis in cows
anaplasma & ehrlichia caused by
rickettsiales (obligate intracellular, tick borne)