Jeef First Aid Micro Part 1-6

Front 1

91. C. botulinum exotoxin?

Back 1

a. Blocks the release of ach.
b. Causes anticholinergic symptoms, CNS paralysis, especially cranial nerves; spores found in canned food, honey (floppy baby).

Front 2

92. Bacillus anthracis exotoxin?

Back 2

a. Edema factor, part of the toxin complex, is an adenylate cyclase.

Front 3

93. Shigella exotoxin?

Back 3

a. Shiga toxin (also produced by E. coli 0157:H7) cleaves host cell rRNA (inactivates 60S ribosome).
b. Also enhances cytokine release, causing HUS.

Front 4

94. S. pyogenes exotoxin?

Back 4

a. Streptolysin O is a hemolysin.
b. Antigen for ASO antibody, which is used in the diagnosis of rheumatic fever. Narcicisstic

Front 5

95. 4 cAMP inducers (either turn it on or off)?

Back 5

1. Vibrio cholerae toxin
2. Pertussis toxin
3. E. coli (ETEC)- heat-labile toxin.
4. Bacillus anthracis toxin.

Front 6

96. Cholera effect on cAMP?

Back 6

a. Vibrio cholerae toxin permanently activates Gs, causing rice-water diarrhoea. Turns the “on” on.

Front 7

97. Pertussis effect on cAMP?

Back 7

a. Pertussis toxin permanently disables Gi, causing whooping cough. Turns the “off” off.
b. Also promotes lymphocytosis by inhibiting chemokine receptors.

Front 8

98. Note: Cholera turns the “on” on and Pertussis turns the “off” off.

Back 8

98. Note: Cholera turns the “on” on and Pertussis turns the “off” off.

Front 9

99. B. anthracis affect toxin effect on cAMP?

Back 9

a. B. anthracis toxin includes edema factor, a bacterial adenylate cyclase (increases cAMP).
b. So cholera, pertussis, and E. coli act via ADP ribosylation to permanenetly activate endogenous adenylate cyclase (increasing cAMP), which anthrax edema factor is itself and adenylate cyclase.

Front 10

100. 3 Primary Effects of Endotoxin (especially LIPID A)?

Back 10

1. Activates Macs
2. Activates complement alternate pathway
3. Activates Hageman factor.

Front 11

101. 3 Effects of Endotoxin activating macs?

Back 11

a. Release IL-1 -> Fever
b. Release TNF-> Fever, Haemorrhagic tissue necrosis.
c. Release NO-> Hypotension (shock).

Front 12

102. 2 effects of Endotoxin activating the alternative complement pathway?

Back 12

a. C3a- Hypotension and oedema.
b. C5a- Neutrophil chemotaxis.

Front 13

103. Effect of Endotoxin activating Hageman factor?

Back 13

a. Activates coag cascade-> DIC.

Front 14

104. 4 phases of Bacterial growth curve?

Back 14

1. Lag phase- Metabolic activity w/out division.
2. Log phase- Rapid cell division.
3. Stationary phase- Nutrient depletion slows growth. Spore formation in some bacteria.
4. Death- Prolonged nutrient depletion and build-up of waste products leads to death.

Front 15

105. Bacterial Transformation?

Back 15

a. Ability to take up DNA from environment (aka “competence”).
b. A feature of many bacteria, especially:
1. S. pneumoniae
2. H. influenzae type B
3. Neisseria
c. SHiN.

Front 16

106. Conjugation F+ x F-?

Back 16

a. F+ plasmid contains genes required for conjugation process.
b. Bacteria w/out this plasmid are termed F-.
c. Plasmid is replicated and transferred through pilus from F+ cell.
d. Plasmid DNA only; no transfer of chromosomal genes.

Front 17

107. Hfr x F- Conjugation?

Back 17

a. F+ plasmid can become incorporated into bacterial chromosomal DNA, termed Hfr cell.
b. Replication of incorporated plasmid DNA may include some flanking chromosomal DNA.
c. Transfer of plasmid and chromosomal genes.

Front 18

108. Transposition?

Back 18

a. Segment of DNA that can “jump” (excision and reincorporation) from one location to another, can transfer genes from plasmid to chromosome and vice verse.
b. When excision occurs, may include some flanking chromosomal DNA, which can be incorporated into a plasmid and transferred to another bacterium.

Front 19

109. “Generalized” Transduction? Also a “specialized” transduction.

Back 19

a. A “packaging” event.
b. Lytic phage infects bacterium, leading to cleavage of bacterial DNA and synthesis of viral proteins.
c. Parts of bacterial chromosomal DNA may become packaged in viral capsid.
d. Phage infects another bacterium, transferring these genes.

Front 20

110. “Specialized” transduction?

Back 20

a. An “excision” event.
b. Lysogenic phage infects bacterium.
c. Viral DNA incorporated into bacterial chromosome.
d. When phage DNA is excised, flanking bacterial genes may be excised w/it.
e. DNA is packaged into phage viral capsid and can infect another bacterium.

Front 21

111. Genes for which 5 bacterial toxins are encoded in a lysogenic phage? ABCDE.

Back 21

a. ShigA-like toxin.
b. Botulinum toxin (certain strains)
c. Cholera toxin
d. Diphtheria toxin
e. Erythrogenic toxin of Streptococcus pyogenes.

Front 22

112. Gram positive with Branching filament-> Anaerobe (not acid fast) vs. Aerobe (acid fast)?

Back 22

a. Anaerobes (not acid fast)- Actinomyces
b. Aerobes (acid fast) – Nocardia

Front 23

113. Gram positive rods?

Back 23

a. Clostridium (anaerobe)
b. Corynebacterium
c. Listeria
d. Bacillus

Front 24

114. What form do all of the Catalase negative bacteria have?

Back 24

a. Chains. They are all strep.

Front 25

115. What form to all of the Catalase positive bacteria have?

Back 25

a. Clusters. They are all staph.

Front 26

116. Gram positive Cocci- Catalase negative?

Back 26

a. Streptococcus (chains).

Front 27

117. Gram positive Cocci- Catalase negative- with no hemolysis (γ-haemolytic)?

Back 27

a. Enterococcus.
i. Growth in bile and 6.5% NaCl – E. Faecalis
ii. Peptostreptococcus (anaerobe).

Front 28

118. Note: Enterococcus can be either α or γ haemolytic.

Back 28

118. Note: Enterococcus can be either α or γ haemolytic.

Front 29

119. Gram positive Cocci- Catalase negative- Complete hemolysis (β-haemolytic) and bacitracin sensitive?!?

Back 29

a. Group A- Strep. Pyogenes

Front 30

120. Gram positive Cocci- Catalase negative- Complete hemolysis (β-haemolytic) and bacitracin Resistant?

Back 30

a. Group B- Strep. agalactiae
b. CAMP test