endospore

Question 1

endospore resistance

Answer 1

Heat, UV radiation, Ioising Radiation, dessication, Lysozyme, chemical, freezing, Hydrostatic presssure

Question 2

Endospore (En) importance

Answer 2

Bacterail survival and dispersion in extreme conditions
-NB in food, industrial and medical microbiology
-Major ways to get rid of B dont work on them

Question 3

Gram positive genera that produce En

Answer 3

-BACILLUS
-Clostridium
-Sporosarcina

Question 4

En position

Answer 4

Central
Subterminal
terminal
terminal with swollen sporangium

Question 5

En layers

Answer 5

-Core
-Inner membrane
-germ cell wall
-cortex
-Outer membrane
-Spore coat
-Exosporium

Question 6

Spore initiation

Answer 6

Depends on environmental conditions: hostile conditions, mostly starvation
-CO2, N depletion will trigger formation

Question 7

Spore formation overview

Answer 7

-Axial filament formation
-Septum formation
-engulfment of forespore
-Ca + dipi
-Coat synthesis
-Completion of cat synthesis, increase in refcartility and heat resistance
-Lysis of sporangium, spore liberation

Question 8

Step 1

Answer 8

Axial filament formation
-Binary fission: Plasma membrane folds inwards
-DNA folds from coiled form to filamentous form known as axial filament

Question 9

Step 2

Answer 9

Septum formation
The membrane invaginates to seperate endospore DNA from mother cell DNA

Question 10

Step 3

Answer 10

engulfment of forespore
-DNA in mother cell is degraded
-Membrane continues to grow and engulfs spore forming a second membrane
-this causes formation of protoplast

Question 11

step 4

Answer 11

Between inner and outer membrane substance resembling cell wall material forms
-Separate layer of PG formed under cortex and is known as the germ cell wall
-Exosporium begins to grow

Question 12

step 5

Answer 12

Coat synthesis
-Protein coat forms outside outer membrane to form exosporium

Question 13

Step 6

Answer 13

Completion of coat synthesis, increase in refractility and heat resistance

Question 14

Step 7

Answer 14

Lysis of sporangium, spore liberation
-Free spore released due to disintegration of sporangium

Question 15

Core

Answer 15

-Protoplast (cell)
-Nucleoid- DNA/RNA
-Cytoplasmic constituents
-pH of core is 1 unit lower
-No high energy compounds present

Question 16

Inner membrane

Answer 16

Plasma membrane
-similar to vegetative cell

Question 17

Germ cell wall (core wall)

Answer 17

Thin shell vegetative cell wall (made of PG)
-same as vegetative cell

Question 18

Cortex

Answer 18

-PG: aa that make up tetrapeptide section are different to vegetative cells
-Thick, elastic (lower cross linkage than vegetative cell)

Question 19

Spore coat

Answer 19

-Multipe proteins are newly synthesised and are insoluble and have high cross linkage
_ Bacillus subtilis have >50_
-known as Coats-OM complex where OM is barely visible

Question 20

Exosporium

Answer 20

Antibodies cant pass through this which facilitates pathogenesis
-Loose fitting
-Complex: protein and glycoprotein that is spore specific
-Not all spores: Bacillus subtilis