1 6/14/2016 Prokaryotic Cell Envelopes Hugh B. Fackrell n Filename: Envelope.ppt

2 6/14/2016 Presentation Outline n Cell wall –Gram reaction –Gram positive vs Gram negative –Gram wall n Cell Capsule n Flagella n Pili

3 6/14/2016 Background Terms & Concepts n Proteins n Membranes (membr.ppt) n Formation of lipid bilayers (membr.ppt) n Prokaryotes n Prokaryotes vs eukaryotes n Evolution of eukaryotes

4 6/14/2016 Prokaryotes Size:1-10  Size:1-10  n Flagella: simple, 2 proteins n Capsule: extracellular polymer n Cell wall: usual, complex n Plasma membrane: no carbohydrates or sterols n Ribosomes: small(70S) n Cell division: binary fission

5 6/14/2016 Cell Envelope n Cell membrane n Cell Wall n Capsule (glycocalyx)

6 6/14/2016 Diagram of prokaryote

7 6/14/2016 Plasma membranes in cell

8 6/14/2016 Phospholipid bilayer

9 6/14/2016 Phospholipid Molecules in Bilayer

10 6/14/2016 Plasma Membrane: Eukaryote

11 6/14/2016 Cell wall is Rigid

12 6/14/2016 Gram Positive Cell Wall

13 6/14/2016 Gram Positive Cells

14 6/14/2016 Gram Positive Cell Wall

15 6/14/2016 Lysozyme Site

16 6/14/2016 NAG & NAM

17 6/14/2016 Gram Negative Cell Wall

18 6/14/2016 Gram Negative Cells

19 6/14/2016 Gram Negative Cell Wall

20 6/14/2016 Gram Negative Cell Wall

21 6/14/2016 Bacterial Cell Walls

22 6/14/2016 Bacterial Wall [detail]

23 6/14/2016 Isolated Murein Layer Isolated Murein Layer

24 6/14/2016 Capsule n Deposited outside of cell wall n Polymer –Carbohydrate –Protein n Antiphagocytic n Receptors n Antigenic Klebsiella pneumoniae negatively stained

25 6/14/2016 Bacterial Capsule Bacteroides thetaiotaomicron n Negatively stained with India ink particles

26 6/14/2016 Bacterial capsule n Method: Differential interference phase contrast microscopy n Capsule appears larger than last slide Bacteroides thetaiotaomicron

27 6/14/2016 Surface attachment by Glycocalyx