(PRELIM) PROKARYOTES EUKARYOTES AND ARCHAE Flashcards
These are organisms that do not contain a true nucleus.
PROKARYOTES
These organisms also do not contain organelles such as Mitochondria ,endoplasmicreticulum,and Golgi apparatus .
PROKARYOTES
All the functions of the prokaryotes take place in the ________ or _________
cytoplasm or cytoplasmicmembrane.
The word “prokaryote” is formed by the words “pro,” which means
before
the Greek word “karyon” which means
nucleus, nut, or kernel
A common example of these cells (prokaryotes) are the ______
bacteria
It is the outer most structure of the bacterial cell
Cell Envelope
It is composed of an outer membrane (Gram-negative bacteria), cell wall, periplasm (Gram- negativebacteria), and plasma membrane.
Cell Envelope
It is also referred to as a peptidoglycan or murein
Cell Wall
It is a rigid structure that maintains the shape of the cell
Cell Wall
It is composed of disaccharide-pentapeptide subunits and teichoic acid and lipoteichoic acid
Cell Wall
Its synthesis and structure have been the primary target of antimicrobial agents.
Cell Wall
It serve as a point anchorage for the flagella
Cell Wall
It determines the staining characteristics of a species.
Cell Wall
What is the two types of cell wall
Gram-positive cell wall
Gram-negative cell wall
It is composed of a very thick protective peptidoglycan (murein) layer.
Gram-positive cell wall
It consists of glycan chains of alternating N-acetyl-D- glucosamine(NAG) and N-acetyl-Dmuramic(NAM)acid.
Gram-positive cell wall
It contains a negatively charged teichoic acid and contributes to the total electric charge of the cell wall
Gram-positive cell wall
It is the prime target of antimicrobial agents, like penicillin, which prevent the synthesis of peptidoglycan
Gram-positive cell wall
It has porins that contribute to the permeability of the cell wall.
Gram-negative cell wall
It contains a periplasmic space which is involved in peptidoglycan synthesis.
Gram-negative cell wall
It does not contain teichoic acid.
Gram-negative cell wall
The 2 layers of the Gram-Negative Cell Wall
Outer membrane / wall
Inner membrane / wall
It is composed of proteins, phospholipids, and lipopolysaccharide(LPS)
Outer membrane / wall
.It is vital in evading the host defenses - the strong
negative charge of the outer membrane is an important
factor in evading phagocytosis
Outer membrane / wall
It contributes to the negative charge of the bacterial surface, which stabilizes the membrane structure.
Outer membrane / wall
It allows hydrophilic compounds to enter the cell through the porins.
Outer membrane / wall
It acts as a barrier to toxic substances that prevents movement inside the cell.
Outer membrane / wall
It is also considered as an endotoxin.
Outer membrane/wall
3 regions of LPS: Lipid A (endotoxin, major component),
core polysaccharide, and antigenic O-specific
polysaccharide
Outer membrane/wall
It is composed of a thin peptidoglycan layer, which is the
reason for its high susceptibility to mechanical breakage
Inner membrane/wall
It has a Gram-positive cell wall structure
Acid-fast cell wall
Aside from a peptidoglycan layer, it contains a waxy layer
of glycolipids and fatty acids (mycolic acid) that is bound
to the exterior of the cell wall
Acid-fast cell wall
Mycolic acid has a strong hydrophobic structure that
affects the permeability of the acid-fast cell wall
Acid-fast cell wall
Some examples of bacterial cells that have this kind of
cell wall are Mycobacterium and Nocardia.
Acid-fast cell wall
Prokaryotes that do not have a cell wall contain sterols in
their cell membrane
Absence of a cell wall
Examples of these are: Mycoplasma and Ureaplasma
Absence of a cell wall
it functions as mitochondria, Golgi complexes and
lysozymes
Plasma Membrane
it acts as an osmotic barrier
Plasma Membrane
it regulates the transport of solute across the membrane
as well as the generation of chemical energy (ATP)
Plasma Membrane
it is the site or respiratory and photosynthesis.
Plasma Membrane
3 Cytoplasmic Structure a Prokaryotic Cell
- Ribosome (Non-Membranous Structure)
- Genome
- Plasmid
It is the site of protein biosynthesis and gives the
cytoplasm a granular structure.
Ribosome (Non-Membranous Structure)
It consists of RNA and Proteins
Ribosome (Non-Membranous Structure)
It is 70S in size and separate into two subunits 50S and
30S
Ribosome (Non-Membranous Structure)
It consist of a single, circular chromosome
Genome
It appears diffused nucleiod or chromatin body that is
attached to a mesosome (sac like structure)
Genome
It is an extrachromosomal, double-stranded element of DNA that
is associated with virulence.
Plasmid
It is located in the cytoplasm and serves as a site for the genes to
encode for antibiotic resistance and toxin production.
Plasmid
It is a self-replicating cellular structure that may be transferred to
a daughter cell (vertical transfer) or may be transferred asexually
through conjugation (horizontal transfer)
Plasmid
It is not essential for bacterial growth thus, a bacterial cell may or
may not contain a plasmid.
Plasmid
- It sometimes disappears during cell division, and it can ma~e
bacteria (mostly Gram- negative bacteria) pathogenic.
Plasmid
Two Kinds of Plasmids:
Large plasmids
Small plasmids
is responsible for production of betalactamases that provide resistance to beta-lactam
antibiotics like penicillin and oxacillin
Large plasmids
is resistant to tetracyclinrd and
chloramphenicol
Small plasmids
They serve as the energy source or food reserve of the bacteria
Inclusion bodies
They are composed mainly of polysaccharides, which lessen
osmotic pressure
Inclusion bodies
Examples: Glycogen, cyanophycin granules, poly-betahydroxybutyrate granules, carboxysomes (cyanobacteria,
nitrifying bacteria, and thiobacilli), gas vacuoles (cyanobacteria,
halobacterium, and Thiothrix), and polyphosphate granules
(volutin or metachromatic granules)
Inclusion bodies
Examples of polyphosphate granules: Babes-Ernst bodies
(Corynebacterium diphtheriae), bipolar bodies (Yersinia pestis),
and Much’s granules (Mycobacterium tuberculosis)
Inclusion bodies
These are small, dormant structures located inside the bacterial cell
Endospores/Asexual spores (Resistant structures)
They aid in the survival of bacteria against external conditions
Endospores/Asexual spores (Resistant structures)
They are produced within vegetative cells of some Gram-positive
bacteria
Endospores/Asexual spores (Resistant structures)
They are composed of dipicolinic acid and calcium ions (calcium
dipicolinate)
Endospores/Asexual spores (Resistant structures)
The locations of these structures aid in the microscopic
identification of bacteria
Endospores/Asexual spores (Resistant structures)
Examples of endospore-forming bacteria:
Badllus and Clostridum
3 Types of Spores According to their Location and the
Associated Organism
a. Terminal spore
b. Subterminal spore
c. Central spore
Terminal spore
Clostridium tetani
Subterminal spore
Clostridium botulinum
Central spore
Badllus anthracis
It is an outward complex of polysaccharides on the bacterial surface
and other cells
Glycocalyx
It helps the bacteria in attaching to the surface of tissues or solid
objects
Glycocalyx
It appears as a capsule or a slime layer
Glycocalyx
2 Types of Glycocalyx
a. Capsule
b. Slime layer
It is an organized material that is firmly attached to the cell wall
Capsule
It is mostly made up of polysaccharide polymers
Capsule
It protects the bacteria (virulence factor) from the attacks of human
defense system cells since it resists phagocytosis and dessication.
Capsule
Slime layer
It is an unorganized material that is loosely attached to the cell wall
It also consists of polysaccharides
Slime layer
It can either inhibit phagocytosis or aid in the adherence of the
bacteria to the host tissue or synthetic implants
Slime layer
It is important in the survivability and the pathogenic ability of
bacteria.
Flagellum (Organ of Locomotion)
It is an exterior protein filament (flagellin) that rotates and causes
bacteria to be motile.
Flagellum (Organ of Locomotion)
5 Flagellar Arrangement
Atrichous
Monotrichous
Amphitrichous
Lophotrichous
Peritrichous
without flagellum
Atrichous
single flagellum on one end
Monotrichous-
single flagellum on both
ends
Amphitrichous
tuff/group of flagella on one
end or both ends
Lophotrichous
spread over the whole surface
Peritrichous
These are hair-like, proteinaceous structures,
about 2 μm in length, that extend from the cell membrane to the external environment.
Pili (Fimbriae)
2 Types of Pili
a. Common/Somatic Pili
b. Sex Pili
they are the organ of attachment - aid in the attachment of
bacteria to issues and surfaces
Common/Somatic Pili
They are considered a virulence factor.
Common/Somatic Pili
Examples of
bacteria with common pili:
Neisseria gonorrhoeae and
Pseudomonas
They are an essential part of the genetic transfer
or conjugation process
Sex Pili
Example of bacteria with sex pili
E. coli (also with
somatic pili
3 WAYS TO
DEMONSTRATE
MOTILITY
Hanging Drop Method
Use of Semi-solid media i.e
SIM
Use of flagellar stains i.e.
Gray’s. Leifson
Alcaligenes
Bacillus cereus
Bacillus subtilis
Campylobacter
Clostridium tetani
Escherichia coli
Helicobacter
Listeria
Pseudomonas
Vibrio
MOTILE BACTERIA
Bacillus anthracis
Klebsiella pneumoniae
Streptococcus
pneumoniae
BACTERIA WITH
CAPSULES
Bacillus
Clostridium
BACTERIA WITH
SPORES
Corynebacterium
Mycobacterium
Nocardia and Actinomycetes
Pasteurella and Bordetella
Babes-Ernst bodies
Much’ s granules
Sulfur granules
Bipolar bodies
BACTERIA WITH INCLUSION BODIES OR
GRANULES
3 MAIN MORPHOLOGICAL SHAPES
- COCCI - (Spherical)
- BACILLUS / BACILLI- (Rod-Shaped)
- SPIROCHETES (Spiral)
singly
Coccus
in pairs
Diplococci
in chains
Streptococci
group-like in clusters
Staphylococci
4
Tetrads
8 (cube-like)
Sarcina
short to long filamentous rods
Coccobacilli
tapered end
Fusiform
comma
Vibrio
align side-by-side
Palisades
