Lecture 16: Bacillus and Clostridium 1 Flashcards
Are Bacillus spp gram positive or negative and what shape
Gram positive rods
Are Bacillus spp spore forming and are they bulging or non-bulging
Spore forming, non-bulging
Where are Bacillus spp found
Soils, decaying organic material, water, human microbiota
Bacitracin is produced by what bacillus spp
B. Licheniformis
Polymixin B is formed by what bacillus spp
B. Poylmyxa
Bt toxin is formed by what Bacillus spp
B. Thurinfinesis
What the results of Bacillus spp for catalase and oxidase tests
Catalase positive, oxidase negative
what does B. Licheniformis cause in sheep and cattle
Sporadic abortions
What does B. Cereus cause in cattle
Abortions and mastitis- acutely fatal or loss of udder quadrant
What does B. Subtilis cause in cattle
Mastitis and abortions
What does the core structure of endospores contain
DNA, ribosomes, lower h20 content
What is the endospore germ cell wall made of
Peptidohylcan
What does the cortex of endospore contain
Less rigid peptidoglycan, 1/2 spore volume
What does the coat of endospore contain
Heavily crosslinked proteins
Identify which is Clostridal spp and which is Bacillus spp. how do you know
left: clostridial- bulging endospores
Right: Bacillus- non-bulging endospores
What is the infectious agent in B. Anthracis
QSpores
B. Anthracis is a CDC category ___ pathogen
Category A priority pathogen
What is the unique part of B. Anthracis cell wall
Secondary cell wall polysaccharide that is covalently bound to peptidoglycan
Anchors S layer to peptidoglycan
What is the S- layer
Surface proteins on B. Anthracis cell wall
What is the Sap protein of S layer
Primary protein during exponential growth
What is the EA1 protein in B. Anthracis S layer
Replaces Sap as cell enters stationary growth phase
What component of the S layer is a strong target for vaccines
EA1 protein
Not all B. Anthracis strains are virulent, what do they carry to become virulent
Two extra chromosomal plasmids
What are the two extra chromosomal plasmids of B. Anthracis
- PXO1
- PXO2
What does PXO1 encode for
- Lethal factor (LF)
- Edema Factor (EF)
- Protective antigen (PA)- binds EF and LF
what does LF +PA toxin in B. Anthracis do
Cleaves host cell MAP kinase proteins leads to host cell death and releases of TNFalpha
What does EF +PA toxin in B. Anthracis do
Increases cAMP levels in host cell, leads to swelling and edema
What does the PXO2 toxin in B. Anthracis encode for
Capsule production.
- caPBCDAE Oberon encodes genes necessary for poly-y-D-glutamic acid capsule
- inhibits phagocytosis
What are the routes of infection for B. Anthracis
- Inoculation via exposed skin
- Ingestion
- Inhalation- likely bioterrorism route, 50% fatal once symptoms arise
What does B. Anthracis do in sheep, goats, and cattle
Staggering, dyspnea, collapse
Often so rapidly fatal that illness is not observed- found dead
What is likely cause of death based on this presentation
B. Anthracis
What does B. Anthracis cause in horses
Fever, chills, severe colic, anorexia, depression, weakness, bloody diarrhea, swelling of neck, sternum, lower abdomen and external genital
Death in 2-3 days post symptoms