BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial...
-
Upload
martha-simon -
Category
Documents
-
view
221 -
download
0
Transcript of BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial...
![Page 1: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/1.jpg)
BIOLOGY OF BACTERIA
![Page 2: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/2.jpg)
LAST DAY
•Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.
![Page 3: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/3.jpg)
TODAY• We will start by looking at our cultures, and providing
colony descriptors.
• We will learn about the Biology of Bacteria• Bacteria structure• Bacterial shapes
• We will look at microscopes again to observe bacterial shapes under the microscope
![Page 4: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/4.jpg)
BIOLOGY OF BACTERIA
• Part 1: Bacterial Cell structure
• Table 24-2 in your text book.
• Bacteria typically are composed of a cell wall, cell membrane, and a cytoplasm.
• Some bacteria have distinctive structures that serve as a protective layer (endospores, capsules, outermembranes)
![Page 5: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/5.jpg)
![Page 6: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/6.jpg)
BACTERIAL CELL WALL
• Both Archaebacteria and Eubacteria have cell walls
• Eubacterial cell walls are made of a molecule known as PEPTIDOGLYCAN• Peptidoglycan is a polymer consisting of sugars and
amino acids, which forms a mesh like barrier outside the bacterial plasma membrane
• Gram Negative bacteria have an outer membrane protects peptidoglycan, meaning some antibiotics are ineffective against GN bacteria.
![Page 7: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/7.jpg)
![Page 8: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/8.jpg)
CELL MEMBRANE AND CYTOPLASM• In Bacteria, cell membrane carries out cellular respiration
(metabolism of bacteria; producing energy) in absence of mitochondria (like in eukaryotes)
• Unlike Eukaryotes, bacteria DO NOT CONTAIN MEMBRANE BOUND ORGANELLES (i.e. no nucles, no golgi apparati, no mitochondria)
• Cytoplasm consists mainly of Ribosomes and DNA
• Bacterial DNA is arranged in a single closed loop
• Aside from the main chromosome, Bacteria also have plasmids, which are self replicating loops of DNA
![Page 9: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/9.jpg)
![Page 10: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/10.jpg)
CAPSULE AND PILI• Many bacterial species produce an outer covering called a
capsule• Protects cell from drying, harsh chemicals and immune
cells
• Glycocalyx:• Fuzzy, sticky capsule around bacteria which allows it to
attach to host cell and tissue
• Pili• Short protein projections on surface of bacteria, which aid
in attachment/adherence to host cells
![Page 11: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/11.jpg)
![Page 12: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/12.jpg)
ENDOSPORE
• Dormant structure produced by some Gram Positive bacteria
• Thick outer covering that surrounds bacterial DNA
• Not reproductive cells, they allow bacteria to survive harsh environmental conditions
•When conditions become favourable, the living bacteria will emerge and continue multiplying
• Formed by the genera Bacillus and Clostridium
![Page 13: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/13.jpg)
![Page 14: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/14.jpg)
BACTERIAL MOVEMENT• Typically propelled by a flagella
• Protein structures, which turn and propel the bacteria in an erratic “run and tumble” motion
• Bacteria can have a single flagellum, a tuft of flagella at one end, flagella at both ends, or flagella completely surrounding the cell
• Some bacteria can mobilize by sliding on a slime layer they produce (myxobacteria) or move in a corkscrew like motion (spirilla)
![Page 15: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/15.jpg)
![Page 16: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/16.jpg)
INTRO TO BACTERIAL SHAPES AND CLASSIFICATION
•Most bacteria have three basic shapes:•Bacilli (rod shaped)• Cocci (spherical/circular)• Spirilla (corkscrew shaped)
![Page 17: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/17.jpg)
BACILLI
• Rod shaped bacterium
![Page 18: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/18.jpg)
COCCI
• Circular/spherical shaped bacteria
• Streptococci (chains) Staphylococci (clusters) Diplococci (dual)
![Page 19: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/19.jpg)
SPIRILLA
• Corkscrew shaped
![Page 20: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/20.jpg)
GRAM POSITIVE V GRAM NEGATIVE
• Bacteria are typically classified as either Gram Positive or Gram Negative based on their color following the Gram staining procedure
![Page 21: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/21.jpg)
GRAM POSITIVE BACTERIA
• Appear purple under the microscope following a Gram stain
• Crystal Violet stains the Peptidoglycan on GP cell wall
• Remember PurPle = Positive
Staphylococcus aureus
![Page 22: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/22.jpg)
GRAM NEGATIVE BACTERIA
• Appear pink following Gram stain under microscope
• GN cells are protected by an outer membrane which prevents the peptidoglycan from being stained.
• The counterstain Saffranin gives GN cells the pink colour
• Remember piNk= NegativeEscherichia coli
![Page 23: BIOLOGY OF BACTERIA. LAST DAY Brief introduction to bacteria, Archaebacteria, and bacterial culturing media.](https://reader033.fdocuments.us/reader033/viewer/2022051116/5697bfde1a28abf838cb1e9b/html5/thumbnails/23.jpg)
TO DO NOW
• Observe some of the different bacterial shapes around the classroom
• Draw them on a blank sheet of paper
•Make sure to label whether they are cocci, bacilli or spirilla, and Gram + or Gram -