loose ends on chapters 3,5,6 summermicrobiology. spore survival dipicolinic acid and ca++ account...
TRANSCRIPT
![Page 1: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/1.jpg)
Loose Ends on Loose Ends on Chapters Chapters
3,5,63,5,6
Loose Ends on Loose Ends on Chapters Chapters
3,5,63,5,6Summer Summer
MicrobiologyMicrobiology
![Page 2: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/2.jpg)
Spore survival• Dipicolinic acid and Ca++ account for 15% of
the total spore mass• Dipicolinic acid theoretically may contribute to
the stability of the nucleic acids which is a contributory to the spore’s survival- The Ca and the dipicolinic acid may enhance the activity of DNA binding proteins that are vital to the spore’s ability to resist radiation
• Calcium contributes to the ability of the spore to resist destruction by oxidizing agents and dry heat – also steam
![Page 3: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/3.jpg)
Spore Structure
![Page 4: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/4.jpg)
Seven Steps and More in Spore Formation
Revisited• Stress or unfavorable environmental
conditions • Replication of DNA• Membrane begins to form to separate
cells – Forespore septum begins to show the formation of the forespore
• Membrane continues to grow and engulfs the DNA into the forespore
![Page 5: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/5.jpg)
Spore formation Continued
• The cortex is laid down and Calcium and dipicolinic acid are accumulated here
• Protein coats then form around the cortex• The exosporium and then the spore coat
are made to surround the spore• At this point the spore structure is
completed
![Page 6: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/6.jpg)
Spore Release• Lytic enzymes destroy the
sporangium releasing the spore• This process takes about 23 hours
in B. subtilis
![Page 7: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/7.jpg)
Flagellar Structure• The M Ring is anchored in the cel
membrane of the bacterium.• A shaft that is attached to the hook and
flagellum extends form the shaft.• In Gram Positive cells the S ring is
attached to the cell wall and does not rotate
• In Gram Negative cells, the P and L rings act as a bearing for the rotating flagellum
![Page 8: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/8.jpg)
Flagellar Motor Proteins• Mot A and Mot B• These form a proton channel for the
establishment of a proton gradient • The Motor proteins also assist in the
anchoring of the complex to cell wall peptidoglycans
• Fli G is the motor protein that generates flagellar rotation
![Page 9: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/9.jpg)
Rotational symmetry of the C ring and a mechanism for the
flagellar rotary motor
• Dennis R. Thomas, David Gene Morgan, and David J. DeRosier
• Proc Natl Acad Sci U S A. 1999 August 31; 96(18): 10134–10139. PMCID: 17855
![Page 10: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/10.jpg)
Reference• The cytoplasmic component of the
bacterial flagellar motor.• I H Khan, T S Reese, and S Khan• Proc Natl Acad Sci U S A. 1992 July
1; 89(13): 5956–5960
![Page 11: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/11.jpg)
Chemoreceptors• MCP – Methyl accepting
chemotaxis proteins• Localized in patches at the ends of
the bacilli in E. coli• React to stimuli through a series of
steps utlizing proteins
![Page 12: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/12.jpg)
Concepts• Conformation change in protein
structure• Methylation of proteins• Phosphorylation of proteins
![Page 13: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/13.jpg)
Increase in nutrient binding
• Environmental stimulus – nutrient molecule
• Nutrient molecule in the gradient binds to the MCP protein( change in conformation)
• Che A is dephosphorylated – loses a phosphate
• Counterclockwise rotation occurs in the bacteria
![Page 14: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/14.jpg)
No nutrient detected in the environment
• No nutrient binding• Che A is phosphorylated( gains a
phosphate group)• Phosphate is then donated to Che Y• Interacts with Fli switch to causes
clockwise rotation or tumbling – random and undirected
![Page 15: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/15.jpg)
Two Component Phosphorelay System
• Two Component Phosphorelay System is similar in response to oxygen, light, hear and osmotic gradients.
![Page 16: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/16.jpg)
Active Transport• Movement against the
concentration gradient from low concentration outside of the cell to higher inside the cyotplasm
• Requires the input of energy to drive the reaction forward
![Page 17: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/17.jpg)
Active Transport and ATP- Binding Cassette
TransportersABC Transporters• Large group of transporters• Two hydrophobic domains in the membrane
and two nucleotide binding domains at the cytoplasmic surfaces
• The membrane spanning portions form a pore • The nucleotide binding domains bind ATP for
the hydrolysis of ATP to produce energy to drive molecules through the membrane
![Page 18: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/18.jpg)
Salmonella ABC transporter
![Page 19: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/19.jpg)
E. Coli and active transport
• The sugars arabinose, maltose galactose, and ribose are transported by this mechanism in bacteria
• Also amino acids may pass through the cell membrane in this manner
![Page 20: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/20.jpg)
Porins• Porins are channels located in the
outer membrane of the Gram Negative bacteria
![Page 21: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/21.jpg)
Omp F
![Page 22: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/22.jpg)
![Page 23: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/23.jpg)
Siderophore
![Page 24: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/24.jpg)
Active transport• Uniport – One ion or molecule moves
against the concentration gradient• Symport – A concentration gradient
established by an ion, drives solute transport of another molecule against the concentration gradient
• Antiport – Sodium is pumped outward in response to an inward movement of protons
![Page 25: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/25.jpg)
Importance of this mechanism
• The sodium pumped to the outside of the cell is also used in transport
• It binds to the outside of a different transport protein.
• When it binds it changes the shape of the protein
• The protein is then able to bind to molecules to move them into the cell
![Page 26: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/26.jpg)
E. coli • Has multiple transport systems for
many nutrients• The diversity of these transport
system provides the ability to survive in diverse environments
![Page 27: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/27.jpg)
Group Translocation• A molecule is transported ito the
cell while being chemically altered• This is energy dependent
![Page 28: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/28.jpg)
PTS• Best characterized system is the
PTS• Phosphoenolpyruvate: sugar
phosphotransferase system• Transports sugars while
phosphorylating them
![Page 29: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/29.jpg)
Components• Two enzymes( EI and EII)• Low Molecular weight – heat stable
protein( HPr)
![Page 30: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/30.jpg)
Steps• High energy Phosphate is transferred
from phosphoenolpyruvate to EII with the help of EI and HPr
• The sugar molecule to be transported is phosphorylated as it goes across the membrane by EII
• EII is specific for the sugar that it transports
![Page 31: Loose Ends on Chapters 3,5,6 SummerMicrobiology. Spore survival Dipicolinic acid and Ca++ account for 15% of the total spore mass Dipicolinic acid theoretically](https://reader033.vdocuments.us/reader033/viewer/2022050909/5697c01b1a28abf838ccf9a7/html5/thumbnails/31.jpg)
PTS