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What are the three domains?
What is the largest bacteria?
What is the smallest bacteria called?
What is the medium bacteria called?
What is the second largest bacteria called?
What are the different cocci that are based on arrangements?
Example of diplococcus
Example and definition of arrangement of streptococci
- Chains of cocci that remain together after divisions in one plane. Examples include:
Tetrad arrangement and example
- cocci that divide in two plains and remain in groups of four.
- Micrococcus luteus
Sarcina arrangement and example
- cocci that divide in three plains and remain attached in cube like growth.
Staphylococcus arrangement and example
- Irregular grapelike clumps of cocci as a result of multiple divisions in random planes.
- Staphylococcus aureus
What are the different straight rods in bacillus?
- In pairs (diplobacillus)
- In chains (streptobacillus)
Coccobacillus shape and example
- Rods that are as wide as they are long, which appear as they are coccus.
- Haemophilus influenzae
Vibrio arrangement and example
- Curved rods that look like a comma
- Vibrio cholerae
Fusiform shape and example
- Straight rods with tapered ends
Spirilum shape and example
- Rigid spiral or corkscrew
Spirochete shape and example.
- Flexible spiral/corkscrew
Helical shape and examples
Long, thin cells or long chain of cells attached end to end, contained in a sheath are (filam...)
The cells are identical to each other and lack differentiation into specialized strucrues
Cyanobacteria (filamentous) examples
Mycelial are found in two forms.
Branching and hyphal
Mycelial Branching filaments
- Hyphal; hayphae-like filaments and are tubes of cytoplasm that are contained within walls. Arranged further into a mycelium, appearing similar to fungi when grown on media.
- Actinomycetes and Mycobacteria
Mycelial (Actinomycetes and myxobacteria) examples.
What is the name of a stalked or appendaged bacteria?
Describe Caulobacter crescentus.
Stalked or appendaged bacteria that is gram negative and is an aquatic bacterium wiht an unusual life cycle.
What is an example of a palisade bacilli?
In what domain are unusual additional shapes found?
What are the unusual shapes found in Archaeobacteria?
- Square flat cells
Radial cells are in what genus and what is an example?
- Genus stella
- Stella humosa
Give an example of the square flat cells found in the unusual shapes of the archeobacteria?
Give an example of the Triangular shaped cells of the unusal shape of the archeobacteria?
Murien or peptidoglycan definition
complex arrangement of sugars (polysaccharides) and peptides found in the cell walls of prokaryotes.
What is the outer membrane composed of in some prokrayotes?
Proteins, glycoproteins and polysaccharides.
What are the various external structure of prokaryotes.
- cell wall
What is the definition of Glycocalyx?
Is a viscous, sticky polymer that is external to the cell wall composed of a network of molecules (polysaccharides or polypeptides/protein) that extend from the cell surface.
What is an example of the organism that uses polypeptides/ protein or poly-d glutamic acid in the network of molecules in the glycocalyx?
What are the different organizaitons of the Glycocalyx?
What is the capsul of the Glycocalyx used for?
To describe the glycocalyx when it is organized and firmly attached to the cell wall.
By what kind of staining ar ecapsules visible?
Negative or capsular staining
What is the slime layer used for in the organization of the Glycocalyx?
It is used to describe the glycocalyx when it is unorganized and loosely attached to the cell wall.
What kind of bacteria use the slime layer for motility?
What is the function of the Glycocalyx?
- Aids in attachment to surfaces of (also in plants or animals) and to other bacteria.
- Helps pathogenic bacteria resist phagocytosis by host phagocytes.
- Protects against desiccation.
- Protects against bacteriophages
- Prevents detergents from entering the cell.
In what domain is the S-layer found?
Bacteria and Archaea
Where is the S-layer located?
outside of the cell wall
What is the Gram-positive bacteria s-layer associated with?
The murein layer
What is the Gram-negactive bacteria associated with in the s-layer that is external to the cell wall?
The outer membrane
can Archaea substitute for the cell wall in the s-layer?
What is the S-layer?
defined as the regular surface layer that has a crystalline appearance and is composed of protein or glycoproteins and is a two-dimensional array.
What is the structure of the s-layer?
Regular, symmetrical (similar to the pattern of floor tiles; Hexagonal, tetragonal, and trimetric.
What is the function of the S-layer?
- Acts as a sieve for low weight molecules, allowing them to enter the cell.
- Protects the cell from:
- Changes in ion and pH fluctuations
- Osmotic pressure
- sieve for light weight molecules
- protects cell
- aids in adhesion to host cells and environmental surfaces
- Helps the organism evade host defenses by protection from the components of complement and phagocytosis by leukocytes (wbcs).
What is the flagella composed of?
basal body, hook, and filament
What are the flagellar arrangements?
- Atrichous (no flagella)
What is the definition of Monotrichous?
- single polar flagellum located at the pole (end) of the cell.
Single flagellum at each end of the cell
Two or more flagella at one or both poles of the cell.
- Flagella distributed over the entire cell surface.
- Proteus vulgaris
What detects chemicals in chemotaxis?
Protein chemoreceptors (methy accepting chemotaxis proteins, mcps)
Where does chemotaxis take place?
periplasmic space or plasma membrane
movement towards (positive) or away (negative) from oxygen.
Movement towards (positive) or away from (negative) conditions of high ionic strength.
What does energy taxis encompass?
- redox taxis
- taxis to alternative electron accors
- chemotaxis to oxidizable substrates
What are Fimbriae or Pili
Structures made up of protein pilin and are arranged helically around a central core (not involved in motility)
Hairlike projecitons that are thinner than flagella and funtion as bristle-like and attach to bacteria surfaces(rocks in aquatic environments adn to host cells)
larger and longer than fimbriae and function in bacterial mating in conjugation.
What does the cell wall components contribute to?
What are the five main arrangements of the bacterial cell walls?
- Gram positive cell wall
- Gram negative cell wall
- Deinococcal cell wall
- Planctomyces cell wall
- Acid-fast cell wall
What is the polymer made up of in Gram positive cell wall?
a sheet of repeating and alternating subuits of N-acetylglucosamine (nag) and N-acetlymuramic acid (nam)
What are the Nag nam subunits cross linked by?
- Peptide interbridges
- Amino acids form a peptide chain to link rows of polysaccharides
What does the peptidoglycan layer contain that is special?
teichoic and lipoteichoic acids which extend from the peptidoglycan
What is the outer membrane made up of?
Unique lipid bilayer that is embedded with proteins and is different from any other in nature and ontains lipopolysaccharides (lps)
What joins the peptidoglycan layer to the outer membrane lay in gram negative cell wall?
What does the Lps consist of?
Lipid A that is embedded in the lipid bilayer, a polysaccharide core, and an O-specific polysaccharide side chain.
Deinococcal cell wall
Combination of gram-negative and gram-positive structures in which there is a thick peptidoglycan layer and an outer membrane and stain gram-positive because of the thick peptidoglycan layer and the outer membran is chemically different from gram-negative bacteria.
Plantomyces cell wall
contains no murein/peptidoglycan but the cell wall consists of a thin layer of protein only.
What is the stain of plantomyces cell wall?
Gram-negative because the protein layer is unable to retain the primary dye.
Which two species also have Acid-fast cell walls?
Mycobacterium and Nocardia
What does acid-fast contain?
Peptidoglycan and mycolic acid, glycolipid.
What connects the peptidoglycan layer to the high molecular weight mycolic acid?
the peptidoglycan layer is linked to arabinogalactan.
The arabinogalactan/mycolic acid layer is overlaid with a layer of polypeptides and mycolic acids that consist of what?
- free lipids
- glycolipids (lipoarabinomannan and phosphoatidyinositol mannosides (pim)
What are porins used for in acid-fast cell walls?
- located on the mycolic acid layer and it is required to transport small hydrophilic molecules trhough the outer membrane of the acid-fast cell wall.
- also used in gram-negative cell wall some times.
what do antibiotics do to the bacterial cell wall?
due to the prescence of murein, bacterial cells can be killed and their growth can be inhibited due to the synthesis and elongation of murein which is affected through the cell wall.
Does the archaeal cell wall have a rigid layer and no murein?
what serves as the cell wall in archea, at some times?
pseudomurein is found in what domain?
- That stain gram-positive have Nat nam interbridges
In Archea, waht does the thick layer consist of that is similar to Gram positive?
complex polysaccharides with no murein.
What are the properties of the cell wall of Arcea that stain Gram (-)?
- No outer membrane
- No pseudomurein
- protein or glycoprotein surface layer
- similar to the planctomycetes