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Bacteria review
1) Bacteria structure and physiology
A) Prokaryotes v Eukaryotes
1) Prokaryotes-no nuclear mem
(1) 50s and 30s
(2) dsDNA
B) Cell wall components in a gram + and a gram
neg.
1) Gram + = lipoteichoic acid, wall teichoic
acid (ion bonding, charge maintenance,
adherence to host
2) Gram neg-no crossbridging
(1) Outer membrane (not lipid)
(a) LPS
(b) Lipid A
(c) O antigen
2) Gram stain
A) CV
B) Iodine- keeps CV inside cell of gm +
C) Alcohol washD) Safranin
3) Mycobacterium cell wall-LAB
4) Synthesis of Peptidoglycan
A) GluNAC and MurNAC form peptide bridges
by transglycosylation
B) Side chains join by transpeptidase
1) Linkage is usually a lys-ala
2) An ala is cleaved when you bind
5) Process and purpose of spore formation
A) Bacillus
B) Clostridium
6) Mycoplasmas
A) No cell wall
7) Capsule
A) Polysaccharide or protein (bacillus anthracis)
B) Block phagocytic receptors
C) Block c3b deposition
D)
8) Events in bacteria growth
A) Lag-bacteria get bigger with no dividing
B) Log-exponential growth
C) Stationary –limit in nutrients
D) Death-detergents, antibiotics etc
9) Oxidizers-LAB
10) Fermenters-LAB
11) Bacteria classification
A) Phenotypic-growth requirements
1) Nutrient uptake
(1) Group translocation-substrate altered
(2) Substrate translocation-substrate
unchanged
(3) Facilitated diffusion
1 of 8
B) Analytic
C) Genotypic-best way
1) MLE electrophoresis-more similar
bacteria are more likely to exchange
DNA
2) DNA restriction profile-RFLP analysislook at chromosomal banding for clones
that have caused a disease
3) DNA base composition4) DNA sequencing-best way but not
practical
5) DNA hybridization
12) Characterization of rRNA for genetic
relatedness
A) Useful because r-RNA is very conserved
13) Gram positive Bacteria
A) Staph. aureus
1) Anterior nares
2) Beta hemolytic
3) Mannitol salt agar
4) Catalase and coagulase positive
5) Capsule
6) Teichoic acids
7) Protein A-binds fc fragments of Abs
8) Clumping factor-bound coagulase binds
fibrin to mask in blood stream
9) Hemolysins-kill RBCs
10) Leukocidins-kill WBC
11) Penicillinase
12) Tunnels through tissue with:
(1) Hyaluronidase
(2) Staphylokinase-lyses formed fibrin
(3) Lipase
(4) Protease
13) Exfoliatin toxin
14) TSS
15) Scalded skin syndrome
16) Pneumonia, meningitis, endocarditis,
osteomyletis, septic arthritis
17) Treat with vancomycin (binds to the dALA)
B) Staph epidermidis
1) Novobiocin susceptible
2) Coagulase neg
3) Polysaccharide slime
4) Heart valve infections
C) Staph saprophyticus
1) Novobiocin resistant
2) UTIs
3) No blood hemolysis
14) Streptococceae
Bacteria review
A) Group A beta hemolytic-(strep pyogenes)
1) Bacitracin susceptible
2) M protein=virulence factor (analogous
to protein A of Staph a.)
3) Antiphagocytic capsule
4) Hyaluronidase
5) Cellulitis
6) Erythogenic toxin-scarlet fever
7) Streptokinases-clot busters digest fibrin
8) Hemolysins
9) DNAases
10) Protein F-binds fibronectin
11) Protein G-binds Ab
12) Associated with rheumatic fever and
glomerulonephritis
13) Necrotizing fasciitis
B) Group B beta hemolytic (s. agalactiae)
1) B for babies
2) Disease of newborns
3) Camp reaction positive-arrow head
C) S. pneumoniae
1) Meningitis, ear infections, pneumonia
2) Optochin sensitive
3) Quelling reaction to see capsule
4) Alpha hemolytic
5) Capnophilic
6) Pneumonococcal surface protein A to
inhibit opsinization
7) Autolysins to release cell components
after grown in culture
8) Pnuemolysins-inhibit cilia function
9) Vaccine-protect against 23 capsule types
D) Viridans strep.
1) Alpha hemolytic
2) Strep mutans
3) Bacteremia
4) Endocarditis
E) Enterococcus
1) Hydrolyze esculin
2) Grow in high NaCl
3) PYR hydrolysis
15) Gram positive Rods
A) Listeria monocytogenes
1) Weakly beta hemolytic
2) Causes food born illnesses
3) Meningitis in neonates
4) Esculin positive
5) Catalase positive
6) MOTILE
7) Umbrella motility
B) Cornybacterium
2 of 8
1) Chinese letters
2) Commensals
3) C. jeikeium-infections in
immunosuppressed paitent
4) C. diphtheria-throat infection
(1) Potent EXOtoxin
(2) Interferes with EF-2 of the ribosome
of cell and cell dies to make
psuedomembrane
(3) Cuases asphyxsia because plugs the
trachea
(4) Toxoid vaccine
5) Bacillus
(1) B. cereus-food poisoning
(a) Beta hemolytic and MOTILE
(b) Catalase positive
(c) Deposits spores in food.
(2) B. anthracis
(a) Endospores
(b) From cattle hide (non lethal)forms lesion on skin
(c) Respiratory infection-lethal
(d) Has a protein capsule
16) Microbial pathogenesis
A) A pathogen must:
1) Cause symptoms
2) Evade the host response, cause
inflammation
3) Be acquired
4) Be able to multiply
5) Transmit to others
B) Virulence factores
1) Evade complement and phagocytosis
(pneumococci)
2) Eliminate T cells-(salmonella)
C) Classifications of microbes
1) Non-pathogenic
2) Normal flora
(1) Effect the immunocomprimised
(2) Produce vitamin K in the gut
3) Opportunistic infections-attack when
immune system is down
4) Disease producing organism
D) Host defense mechanisms
1) Innate immunity
2) Acquired immunity
3) NK cells
4) Inflammation
E) What is used to fight bacteria $$$$
1) Extracellular bacteria-Abs, complement,
phagocytes
Bacteria review
2) Intracellular bacteria-Th1 cells,
macrophages, and CD8 T cells
3) Viruses-Abs, interferons, NK cells
17) Neisseria
A) N. meningiditis
1) Oxidase positive (enterobacteracea are
oxidase neg)
2) Capnophilic
3) Fastidious
4) Polysacc. Capsule, LPS, IgA protease
5) Nasopharynx to blood to CSF
6) Oxidizes glucose and MALTOSE
7) Humans only reservoir (like shigella)
8) Asplenia and complement deficiency are
at risk
9) Bacterimia
10) Purpura fulminans
11) Waterhouse-friderishsen syndromeadrenal hemorrhage
12) Empyema-exudate over brain
13) New conjugate vaccine
B) N. gonorrhea
1) Nonmotile, capnophilic
2) Pili enhance attachment
3) IgA protease
4) No immunity because antigenic variation
5) Urethritis in males
6) Oxidizes GLUCOSE
7) Nucleic acid amplification and test on
Thayer martin agar (chocolate +
Anitbiotics)
8) Arthritis, proctitis, PID, pharyngitis,
ophthalmia neonatorium (Chlamydia
does this too)
18) Chlamydia
A) C. trachomitis
1) Obligate intracellular
2) NO Peptidoglycan!!! Makes hard for
antibiotics
3) Prevents phagolysosome fusion
4) Elementary body-infectious form
5) Reticulate-replication form
6) Not as pyogenic eye infection as the
gonge (gonorrhea)
7) Most common STD
8) Lymphogranuloma venereum
9) No vaccine
B) C. psittaci
1) Parrot shit
2) Diagnose with Ab titer
3) Respiratory infection
3 of 8
C) C. pneumophila
1) Atherosclerosis
2) CAD
19) Spirochetes
A) Treponema pallidum
1) Primary, secondary, latent, tertiary
2) Chancre, rash, no signs, CV, gumma,
CNS, Tabes dorsalis,
3) Hutchinsones incisors, mulberry molars
4) Darkfeild microscopy
5) 8th nerve deafness
6) Saber tooth tiger shins
7) Non treponemal test-RPR and VDRL
can give false positives
8) Treponemal-TPPA will give positive test
for life
B) Borrelia
1) Stain with giemsa
2) Lyme disease
3) Ixodes tick-not in AL
4) ECM rash
C) Rickettsiae
1) Vectors
2) Have DNA AND RNA
3) R. Ricketsii-Vasculitis=RMSF
4) Monocyte ehrlichiosis-ehrlichia
chafeensis
5) Typhus fever-R. typhi
20) Anerobes
A) Bacterioides fragilis
1) Necrotizing fascitis
2) Grows on bile
B) Prevotella melaninogenica
1) In the mouth
C) Fusobacterium
1) Nonspore forming
2) URT and colon
3) Pulmonary abscess from vomit
4) Mixed flora
5) Pointed ends
D) Actinomyces israelii
1) Sulfur granules
2) Dacyrocystitus-blockage of tear ducts
3) Actinomycosis-lumpy jaw
E) Propionobacterium
1) In normal skin flora
F) Lactobacillus
1) Normal flora of vagina
G) Clostridium
1) Tetani
2) Botulinum
Bacteria review
3) Perferingins-gas gangrene
(1) Box car
(2) PLC
(3) Nagler test
(4) Double zone of hemolysis
4) Dificile-resistant to broad spectrum
antibiotics
21) Heamophilus
A) X and V factors
B) Person to person
C) IgA protese
D) 5-10% CO2
E) No hemolysis
F) Capsule
G) Chocolate agar
H) Satellism with s. aureus
I) Otits media, Sinusitis, bacterimia
J) Capsule b, polysaccharide,protein carrier
vaccine
K) Pink eye and community aquired pnemonia
L) Ducreyi
(1)
STD
M) Aegyptis
1) Conjunctivitis
22) Bordatella
A) Gram –
B) Capsule
C) Strict aerobe
D) Oxidize but don’t ferment
E) Pertussis
1) 3 stages
(1) Catarrhal-1-2 weeks
(2) Paroxysmal-1-6 weeks
(3) Convalescent-months
2) No reservoir
3) Produces exotoxins after it adheres
4) Pertussis Toxin-adherance
(1) Increase cAMP
(2) Inhibit phagocytosis
5) Lethal toxin
6) Tracheal toxin
7) Endotoxin (LPS)
F) DaPT - acellular vaccine, not whole bugs like
DPT
23) Legionella pneumophila
A) Legionarres-old men with COPD and
emphysema
B) In air conditioner
C) Fastidious
D) Facultative intracellular
4 of 8
E) No ferment, No person to person
transmission (inhaled), NO vaccine
F) Prevent phagolysosome fusion in
macrophage
G) BCYE agar, silver staining, FAb, urine
polysaccharide Ag, to detect
H) Cell mediated response most important
24) Moraxella catarrhalis
A) URT
B) Gram neg coccus
25) Mycoplasma
A) Very small
B) Smallest free living
C) No cell wall-susceptible to drying out
D) Extracellular growth on mucosal membranes
E) Pneumoniae
1) Cilia
2) Person to person transmission
3) Cytotoxic after attachment
4) Walking pneumonia
5) Look for IgM (children) or
seroconversion with IgG and IgM
(adults) to detect
6) Role in asthma
7) Spread through households
F) Hominis-opportunistic infection
1) Postpartum endometriitis
G) Genitalium
H) Ureaplasma species
1) Thought ot cause non chlamydial
urethritits
26) DNA structure
27) DNA replication
A) Initiated at OriC
B) Helicase unwinds
C) DNA polymerase adds bases to 3’ end
D) Leading strand, lagging strand (goes 5’ to 3’)
E) Okazaki fragments
28) PCR
A) Denature DNA
B) Add complementary oligosaccharides
C) Add nucleotides
D) Synthesize strand with Taq DNA polymerase
29) Prokarytotic gene organization
A) Operon-group of genes. Usually gives you a
long mRNA. PCR will tell you if you have
an operon.
B) Promoter region
1) Operator
2) -10 (TATATT) and -35 region
(TTGACA)
Bacteria review
3) TSS at +1
4) RNA polymerase binds the -10 and -35
C) Transcriptional apparatus
1) Beta, Beta prime, 2 alphas, omega, and
sigma factor (active) are in the RNAp
2) RNAp=molecular engine of cell
3) Termination sequence-G-C rich hairpin
loop
D) Transcriptional sequence
1) Initiation
2) Elongation
3) Continued elongation
4) Termination
30) Lac operon (E. Coli)
A) Negative regulation-(must be switched off)
1) repressor binds to the operator and
transcription is blocked
2) Repressor competes with RNAp
B) Induction of the Lac operon
1) Lactose binds to the active repressor and
transcription still occurs
C) Positive control-(must be switched on)
1) Lactose blocks active repressor
2) CRP (CAP)binds to the RNAp and
transcription occurs
3) Need an inducer (CRP) and a repressor
(lactose)
31) Tryptophan operon
A) Have an inactive repressor
B) Trp is the corepressor
C) If Trp is around the bacteria wont produce
more Trp.
D) If Trp is low transcription will occur
32) Attenuation-Antitermination-leader sequence
A) High Trp-DNA forms a hairpin terminator
between 3 and 4---no transcription
B) Low Trp-anti-terminator hairpin between 2
and 3 ---- transcription
C) No protein synthesis-terminator between 1
and 2 and between 3 and 4---no polycistronic
Trp mRNA
33) Two component system
A) Sensing domain-(kdpD)relays signal to C
terminus, histadine kinase is phosphorylated
and then it activates the RR
B) Response regulator (KdpE)-once activated
binds to RNAp and activates gene expression
34) Mutation, Repair and Recombination
A) Transition-purine to purine (A to G)
B) Transversion-purine to pyrimidine
5 of 8
C) UV light will cause a thymine dimmer
in DNA
D) Repair
1) Direct-enzymatic removal
2) Excision
3) Post-replication
4) SOS-recA gene encodes for
recombination proteins
5) Error prone repair-last resort
35) Gene exchange
A) Transformation-naked DNA
B) Transduction-virus (bacteriophage) mediated
C) Conjugation-tubes between bacteria
36) Separate DNA via agarose gel electrophoresis
37) Plasmids
A) Contribute to antibiotic resistance
38) Chromosomal DNA
A) Can be taken up by other bacteria. For
example the DNA to make a capsule can be
taken up by a bacteria without a capsule.
39) Bacteriophage
A) Lytic life cycle-phage particles eventually
lyse
B) Lysogenic life cycle-phage DNA gets cut out
of host DNA and some host DNA comes
with it.
40) Gene transfer
A) Generalized transduction-Virus carries
random DNA
B) Specialized transduction-virus carries
specific genes from donor to recipient
C) Conjugation-plasmid or chromosomal DNA
can be transferred
D) Transposons-Mobile genetic elements that
can transfer DNA within a cell from one
position to another in the genome or between
different molecules of DNA (e.g., plasmid to
plasmid or plasmid to chromosome)
41) Recombinant DNA technology
A) Transposon mutagenesis to ID virulence
factors
B) Can produce 5-10 pounds of E. Coli with
recombinant DNA tech
C) REstiction enzymes-read palindromic
sequences (EcoR1)
D) Chakrobarty can degrade oil
42) Enterobacteriaceae-all can cause UTI, wound
infection, and pneumonia
A) Gram neg-LPS, lipid A, O antigen
1) H antigen-flagell
2) K antigen-capsule
Bacteria review
(1) O 157:H7-E coli strain found in
spinach
B) Facultative anaerobes
C) Ferment glucose
D) Oxidase neg.-(oxidizers don’t ferment but
fermenters can oxidize) pseudomonas is
oxidase positive so good to distinguish in
normal flora from EB
E) Catalase posterior
F) Nitrate posterior
G) Peritrichous flagella
H) ID with genetic relatedness of the highly
conserved 16s RNA
I) Normal Flora
1) Immunological stimulation
2) Opportunistic infection
3) Compete with other bacteria in gut
J) E. Coli
1) Lactose (MacConkey) and indole
positive
2) Shigella and salmonella are lactose neg!
3) Cause UTIs from anatomy of
women,catheterization etc
4) Peritonitis-form ruptured gut.
5) Septicemia
6) Wound infections
7) Diarrhea
8) EPAC(infant diarrhea), EAEC and
ETEC (travelers), EHEC (hemolytic
uremic syndrome O157:H7),
Enteroinvasive E. Coli (bacillary
dysentery which is a little blood in the
stool with watery diarrhea)
K) Klebsiella pnuemoniae
1) Lactose pos.
2) Capsule
3) B-lactamase-resistent to penecillins
4) Non-motile
5) Cuased by vomiting, nosocomial,
diabetes, respirator
L) E. cloacae and aerogenes
1) Lactose pos.
2) Non-motile
3) UTIs
4) Cephalosporinase
M) Protease mirabilis, Protease vulgaris
1) Urease positive!!!!!!
2) Highly motile, swarm
3) H2S positive
4) Tetracycline, ampicillin and
cephalosporin resisntant
6 of 8
43) Diarrhea
A) ETEC-watery secretory travelers diarrhea
(malfunction of the Na absorption
mechanisms)
1) Labile toxin
2) Stable toxin
B) O157:H7-bloody diarrhea
44) Salmonella enterica
A) Lactose neg
B) H2S positive
C) Causes
1) Typohiod fever
2) Enterocolitis-Food poisoning
(typhimuriam, Enteritiditis, Newport)
3) Bacteremia
D) Takes 10^5 salmonella to cause infection
E) S. enterica-in normal flora of chickens.
Invades epithelial cells of humans
F) XLD-shows H2S as black colonies
G) S. typhi (typhoid fever)
1) Vaccine-killed whole S. typhi. LPS
present can give side effects. OR a live
ty21a vaccine administered in capsules
2) Pathogenesis: mucosa to blood stream to
spleen, liver, to secondary bacteremia
H) EIEC-looks like shigella
I) EHEC-bloody stool
1) HUS (hemolytic uremic syndrome)binds Gb3 or Pk antigen which is high in
renal glomeruli of kids and in platelets in
adults
2) O157:H7-sorbital neg.
J) Shigella
1) Non-motile
2) Lactose neg
3) Very infectious-takes 200 organisms to
get infection
4) 4 species
5) Transmitted by feces, fingers, food, flies,
and water
K) Yersinia entercolitica
1) Ulcerations in appendic
2) Normal in pigs and animals
3) Transmitted by contaminated food
L) Campylobacter jejuni and C. coli
1) Gram neg in chickens, cattle and pets
2) Bloody diarrhea
3) Transmitted by food or water
M) Vibrio Cholerae
1) Gram neg.
2) In oysters and seawater
Bacteria review
3) Watery diarrhea
4) High dose to infect
45) Mycobacterium Tuberculosis
A) Acid fast-stain with carbolfuschin
B) Cause disease in AIDS patients
C) Two obligate pathogens: M. tuberculosis and
M. leprae-hansens disease
D) Mycolic acids, abinoglactan, acyl lipids, PG,
orins in cell wall
E) Obligate aerobes
F) Humans are the only host
G) Deacreasing in the U.S. since 80s because of
AIDS epidemic
H) Rough appearance on a slide
I) Survives drying but not UV rays, chlorine,
phenols, and pasteurization
J) Transmitted by droplets
K) 95% of people become latent once exposed
and 90% never reactivate
L) Synergistic with HIV
M) Types
1) Adult-upper lobes of lung
2) Childhood-middle lobes
3) Acute Tb pneumoniae-AIDS
4) Miliary-tubercles all over their body
5) Cold abscess-in a localized area (needle
stick)
6) Addisons-adrenal insufficiency
N) Diagnosis
1) AFB smear-quickest
2) Tuberculin skin test-15mm=infection,
10mm=at risk, 5mm=early,
immunosuppressed at risk
3) Chest radiograph
4) AFB culture-way you really tell if
someone has Tb
5) Digestion with NaOH (Tb survives but
nothing else does) or N-acetyl-Lcysteine
6) Centrifuge
O) Prevention
1) BCG vaccine
2) INH (isoniazid), prophylaxis
3) Chemotherapy
46) M. avium
A) Soil, hot water like showers
B) Transmit through respiratory or GI
C) Resistant to many antimycobacterial drugs
47) M. kansasii
A) Photochromogen
48) M. marinum-photochromogen
7 of 8
A) In water and fish tanks
B) lymphocutaneous
49) M. scrofulaceum
A) Granulomatous cervical lymphadenitis
50) M. fortuitum-M. chelonei complex
A) Skin, pulmonary
B) Rapid growers
51) M. leprae
A) Hansens disease
B) Tuberculoid leprosy
1) Hypopigmentation
2) Anesthesia
3) Cooler parts of body
4) Detected with AFB test
5) Non progressive
6) Intact CMI
C) Lepromatous
1) Depressed CMI
2) Bacteremia
3) Leonine facies
52) Nocardia-strictly aerobic actinomycete
A) Partially acid fast, gram positive
B) N. asteroids most common
C) 4 types
1) Pulmonary
2) Localized extrapulmonary and systemic
3) Cutaneous
4) Mycetomas
D) Susceptible to sulfonamides
E) Found in soil
53) Antibiotics
A) Cell wall
1) Beta lactams-mimic D-ALA-D-ALA
(1) Penicillin, cephalosporin,
carbapenum
2) Non beta lactams
(1) Cycloserine-cant make D-ALA
(2) Glycopeptides (vancomycin)-binds
d-ala
(3) Bacitracin-binds lipid carrier (good
against gram positive)
(4) Isonazid-inhibits mycolic acid
synthesis (Tb treatment)
B) Ribosome
1) Tetracycline-prevent attachment of tRNA-AA to 30s (Gram + , ricketsia and
Chlamydia, mycoplasmas,STDs)
2) Aminoglycosides-bind 30s and
inactivate the initiation complex (gram –
aerobes), degraded by stomach, take IV
Bacteria review
3) Macrolides-bind 50s and prevent release
of t-RNA (mycoplasmas, Chlamydia,
legionella)
4) Oxazolidinones-bind 50s and prevent
formation of initiation complex
5) Chloraphenicol and clindamycin-bind
50s and prevent peptide bond formation
(treat anaerobes)
6) Streptogramins-bind 50s and prevent
peptide elongation and premature release
C) Cell membrane
1) Polymyxin
2) Daptomycin-depolarization of mem,
influx of K
D) DNA replication
1) Rifampin-prevents transcription, cant
use alone
2) Metronidizole-only anaerobes, directly
damages DNA
3) Flouroquinolones-inhibit DNA gyrase
E) Antimetabolites
1) Sulfonomides-mimic PABA (precursor
for folic acid)
2) Trimethoprim-inhibits dihydrofolate
reductase
54) Antibiotics 2
A) MIC-minimum inhibitor concentration
B) MBC- minimum bactericidal concentrationlowest # of antimicrobial to kill 99.9% of
bacteria
C) Bacteriostatic-inhibits growth,
D) Bacteriocidal-kills bacteria, good in
immunosuppressed
E) Agar disc diffusion-qualitative test
F) Agar gradient diffusion-quantitative test
55) Desirable properties of an antibiotic
A) Selective toxicity
B) Water soluble
C) Bactericidal
D) High conc. in serum for several hours
E) Broad spectrum
F) Minimal effect on normal flora
G) Low potential for inducing resistance
H) Minimal side effects
56) Drug resistance increasing because
A) People are sicker
B) New devices and procedures
C) Ineffective infection control
D) Increase in antimicrobial prophylaxis
E) Emperic polymicrobial antimicrobial therapy
57) Characteristics favoring resistance
8 of 8
A) Ability to exchange DNA
B) Ability to survive adverse environments
C) Easilycolonize, infect,and transmit between
people
D) Reservoirs in the body
58) Types of resistance
A) Innate-gm negs are resistant to vancomycin
because it is too big to get inside cell,
isonazids don’t work on gm – because no
mycolic acids
B) Acquired-clinically worrisome
59) Mechanisms of antibiotic resistance
A) Enzyme inactivation-beta lactamase
B) Metabolic bypass-bypass folic acid
C) Decrease permeability-antibiotic cant get into
cell
D) Active efflux-of antibiotic
E) Altered targets-mutate the DNA gyrase and
quinolones cant work
60) Some drug resistant bacteria
A) S. aureus, E. faecium, S. pneumoniae, ESBLproducing E. coli and Klebsiella spp., and P.
aeruginosa.