Unit 1 Flashcards
Study of microorganisms
Microbiology
Large diverse group of microscopic organisms
Microorganisms
Microorganisms exist as
Single cells
Product of evolution
Microorganisms
Evolution is the biological consequence of
Natural selection
Microorganisms are group according to
Classification
Give the 8 classification of microorganisms
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
It is the most inclusive taxa
Kingdom
It established the rules and guidelines for naming a microo
International code of nomenclature of bacteria or bacteriological code
The genus always starts with
Capital letter
The species always starts with
Lowercase
Naming bacteria are always?
Italicized (15 degrees) and underlined
Process of delineating a microorganisms features
Microbial identification
2 methods for microbial identification
Genetic and phenotypic characteristics
Give the 8 criteria of phenotypic characteristics
Macroscopic morphology
Microscopic morphology
Staining characteristics
Nutritional requirements
Resistance profiles
Antigenic properties
Sub-cellular properties
Chemataxonomic properties
3 staining characteristics:
Gram stain
Acid fast stain
Periodic-Acid Schiff
Most common/major way of classifying bacteria in diagnostic microbiology
Gram staining
Bacteria lacks…
Nuclear membrane
True nucleus
Bacteria are (prokaryotes or eukaryotes)
Prokaryotes
Give the 7 organelles present only in Eukaryotes
Golgi bodies
Membrane bound organelles
Lysosomes
Chloroplast
Nucleus
Mitochondria
Endoplasmic reticulum
Location of prokaryote
Location of eukaryote
: nucleoid
: nucleus
Chromosomal DNA
Prokaryotes
Eukaryotes
: circular
: linear with histones and proteins
Electron transport for energy
Prokaryotes
Eukaryotes
: Cell membrane
: Mitochondria and chloroplast
Do prokaryotes have sterols?
Do eukaryotes have sterols?
: no
: yes
What is absent in prokaryotes?
7 organelles
Sterols
Cilia
Cell envelope structure consists of:
Capsule
Cell wall
Cell membrane
Slime layers
Cell membrane AKA
Plasma membrane
Function: act as an osmotic barrier and location for electron transport chain
Cell membrane
Prokaryotic cell membrane are made up of
Phospholipids
Proteins
Eukaryotic cell membrane are made up of
Phospholipids
Proteins
Sterols
Maintains the size of the cell
Cell membrane
Function: maintain cell shape, prevent cell from bursting due to high internal osmotic pressure, prevents mechanical disruption
Cell wall
This bacteria does not have cell wall and poorly stains with gram stain
Mycoplasma spp.
Type of cell wall that is very thick in peptidoglycan layer
Gram positive cell wall
AKA AS MUREIN LAYER
Peptidoglycan layer
Unique to gram positive bacteria
Teichoic acid
Lipoteichoic acid
Anchored to the murein layer
Teichoic acid
Anchored to the plasma membrane
Lipoteichoic acid
Unique to gram negative bacteria
Outer membrane
Periplasmic space
Outer membrane consists of:
Lipopolysaccharides
Proteins
Phospholipids
LPS 3 regions
O-specific polysaccharide
Lipid A
Core polysaccharide
AKA as endotoxin, and responsible for fever and shock
Lipid A
It is a type of cell wall that has a thinner layer of peptidoglycan layer, and less affected by antibiotics
Gram negative cell wall
It is the space between the outer membrane and inner membrane,
Gel like matrix
Absent in gram positive
Periplasmic space
Outer membrane acts as sieve allowing water soluble molecule to enter through protein channel called
Porins
2 examples of microorganisms found in Acid fast cell wall
Mycobacterium spp
Nocardia spp
Major component of the acid fast cell wall, which makes gram staining very difficult
Mycolic acid
Mycobacterium stains color:
Nocardia stains color:
Faint blue
Dark blue
Made of high molecular weight polysaccharides polymer
Capsules
Removal of capsule is done by
Boiling a suspension of the microorganisms
Staining the capsule will cause the appearance of what pattern
Halo-like pattern
Important function of slime layers
Stabilizes the cell
AKA as biofilms
Slime layers
Bacteria present in the artificial prosthetics and in dwelling devices
Enterococcus spp.
Coagulase negative staphylococcus
Klebsiella pneumoniae
Pseudomonas aeruginosa
Staphylococcus spp
Streptococcus spo
Fungi present in the artificial prosthetics and in dwelling devices
Candida albicans
Bacteria in food borne contamination
Listeria monocytogenes
This structure will help the bacteria to be motile
Flagella
TRUE OR FALSE
all bacteria are motile
False
Type of flagella
- no flagella (non-motile)
Atrichous
Type of flagella
- one polar flagellum in one side
Monotrichous
Type of flagella
- flagella on both ends
Amphitrichous
Type of flagella
- tufts at one end
Lophotrichous
Type of flagella
- tuft of flagella at both ends
Cephalotrichous/amphilophotrichous
Type of flagella
- flagella all around
Pertrichous
In motile gram negative bacteria
Embedded in the lipid bilayer
L Ring
In motile gram negative bacteria
Embedded in the Periplasmic space
P Ring
2 important rings in motile gram negative bacteria
S and M ring
In motile gram negative bacteria
Attached to the M ring
S ring
Flagellation of prokaryotes
Clockwise or counter clockwise rotation
Prokaryotes movement are powered by
Proto motive force (chemiosmosis)
Eukaryotes movement are made by
Chemismosis or ATP
4 types of locomotion produced by prokaryotic flagella
Propulsion/swimming
Swarming motility
Twitching motility
Gliding motility
Types of locomotion flagella
- forward, reverse, tumbling
And give example of a bacteria
Propulsion or swimming
E coli
Proteus spp movement
Swarming motility
Prokaryotic flagella that uses pili or flagella
Gliding motility
Type of locomotion by Prokaryotic flagella which uses pili as hook
Twitching motility
3 genetic recombination
Transformation
Transduction
Conjugation
Mode of transfer/exchange between homologous regions of two DNA molecules
Genetic recombination
Helps in forming new combination of genes on a chromosome and enables genetic diversity
Genetic recombination
Transfer of bacterial genes using bacteriophage
Transduction
Cells that can take up dna are called
COMPETENT
uptake and incorporation of free or naked DNA into the bacterial cell
transformation
Phase that the infected bacterial cell lyses due to viral infection causing the release of more bacteriophage
Lytic phase
In this phase, the bacteriophage is now called “temperate phage”
Lysogeny
Transfer of genetic material from a donor (male) bacterium into a recipient (female) bacterium
Conjugation
4 types of cell interior
Cytosol
Nucleoid
Plasmids
Endospores
a cell interior, which is gel like substance and it is the main sire of metabolism for bacteria
Cytosol
Storage form of glucose
Glycogen
Store inorganic phosphates
Polyphosphate granules
It is part of the cytoplasm; without nuclear membrane
Nucleoid
Contains highly coiled linear DNA with intermixed RNA, polyamines and proteins
Nucleoid
AKA as jumping genes
Transposons
Mobile dna pieces that jump from one chromosomal location to another, which also carry drug resistance genes located in plasmids
Transposons
TRUE OR FALSE
jumping may not cause loss of phenotype or an appearance of a new phenotype
FALSE
Contains genes that enable bacteria to resist/adapt to its harsh environment
Plasmids
According to morphology
Cocci
Circular in shape
According to morphology
Bacilli
Rod shaped
According to morphology
Coccobacilli
Ovoid
According to morphology
- pointed end or tapered end
Fusiform
According to morphology
- no definite shape
Pleiomorphic
According to gram staining
Components:
Preservation of the structure which uses heat
Fixation
According to gram staining
Components:
Stabilize the cell wall, act as a bridge between stain and bacteria
Mordant (Gram’s iodine)
According to gram staining
Components:
Primary stain
Crystal Violet
According to gram staining
Components:
Use as decolorizer
Alcohol or alcohol acetone
According to gram staining
Components:
Use to counter stain
Safranin
According to gram staining
Components:
Counter stain - allows better staining of anaerobic bacteria
Carbol fuchsin
Retains the primary stain
Gram positive bacteria
Primary stain is washed away due to the thin peptidoglycan layer and allows the counterstain to enter
Gram negative bacteria
Bacteria seen in gram positive bacteria
Staphylococcus spp
Streptococcus spp
Final stain of gram positive bacteria
Deep blue or Purple
Final stain of gram negative bacteria
Pink or red
Bacteria seen in gram negative bacteria
Pseudomonas spp.
enterobacteriaceae family
Gram variable AKA as:
Interdeterminate
Ghost
Neutral
Atypical
Final stain in gram variable
Mix of Pink or purple
Bacteria Seen in gram variable
Bacillus spp.
clostridium spp.
Controls in gram positive
Staphylococcus aureus
Controls in gram negative
Escherichia coli
According to Acid fast staining
3 types:
Hot method: Ziehl-Neelsen method
Cold method: Kinyoun method
Truant method: auramine-rhodamine fluorochrome method
According to Acid fast staining
Method that uses without heat and increased the concentration of carbol fuchsin as the primary stain
Cold method
According to Acid fast staining
Introduce the use of carbolic acid (phenol) as a mordant
Franz Ziehl
According to Acid fast staining
Introduce the use of basic fuchsin as a seconda stain
Friedrich Neelsen
According to Acid fast staining
Components of hot and cold method
Primary stain:
Carbol fuchsin hot
Kinyoun carbol fuchsin cold
According to Acid fast staining
Components of hot and cold method
Decolorizer:
Acid alcohol (HCL in 95% ethanol)
According to Acid fast staining
Components of hot and cold method
Counterstain:
Methylene blue
According to Acid fast staining
- uses ultraviolet fluorescent microscope
Truant method
According to Acid fast staining
Truant method:
Fluorescent stain
Auramine O - Rhodamine B stain
According to Acid fast staining
Truant method:
Decolorizer:
Acid alcohol (HCL in 70% ethanol)
According to Acid fast staining
Truant method:
Counterstain
Potassium permanganate
This bacteria can be found in acid fast stain if you use tap water
Mycobacterium gordonae
Final stain of acid fast positive
Red
Final stain of acid fast negative
Blue
According to complexity:
Prokaryotes
Eukaryotes
According to symbiosis
- relationship between two organism in which one harm the other
Parasitism/pathogens
TRUE OR FALSE
Parasite May inadvertently inflict harm on its host
True
According to symbiosis
- relationship between two organisms where both benefit
Mutualism
According to symbiosis
- relationship between two organisms where one benefits and the other is unharmed
Commensalism
Commensalism are called
Partners
Phoresis are called
Phoronts
According to symbiosis
- relationship between two organisms “traveling together “ and do not have any dependency on each other
Phoresis
According to nutrition
Organisms that can build their own food
Autotrophs
According to nutrition
Organisms that cannot build their own food
Heterotrophs
According to nutrition
Heterotrophs type ; organisms that feed in dead and decaying matter
Saprophytes
According to nutrition
Heterotrophs type; acquire nutrition from living hosts
Parasite/pathogens
According to nutrition
Autotrophs type ; use sunlight to create atp
Photoautotrophs
According to nutrition
Autotrophs type ; uses inorganic chemical processes
Chemoautotrophs
According to temperature requirements
Optimal growth at 10-20
Psychrophiles
According to temperature requirements
Optimal growth at 20-40
Mesophiles
According to temperature requirements
Optimal growth 50-60
Thermophiles
Campylobacter jejuni can grow at what degree celsius
42 degrees celsius
According to atmospheric requirements
Require oxygen for growth
Aerobes
According to atmospheric requirements
Required reduced oxygen level of growth
Ex. Campylobacter jejuni requires 5% to 6% O2
Microaerophiles
According to atmospheric requirements
Organisms that cannot grow in the presence of oxygen
Anaerobes
According to atmospheric requirements
Can grow with or without oxygen
Facultative anaerobes
According to atmospheric requirements
Facultative anaerobes
With oxygen
Aerobic respiration
According to atmospheric requirements
Facultative anaerobes
Without oxygen
Faster growth
Can survive in the presence of oxygen but does not need oxygen for metabolism
Aerotolerant anaerobes
According to atmospheric requirements
Organisms that requires 5-10% CO2
Capnophiles
According to pH requirements
pH level less than 5
Ex. Normal flora on the Vagina (Lactobacillus spp)
Acidophiles
According to pH requirements
pH level 5-8
Neutrophiles
According to pH requirements
Most bacteria are
Neutrophiles
According to pH requirements
pH level 8-11
Alkaliphiles
According to pH requirements
A pathogen that grows at pH of 8 and can survive harsh environment such as pH of 11 but is inactivated by the acid in the stomach
Vibrio cholerae
According to osmotic pressure
Seen in environment with high (inorganic solutes) salt concentration
Halophiles
According to osmotic pressure
Seen in environment with high salt concentration. Less than 0.2 M
Non-halophiles
According to osmotic pressure
Seen in environment with high organic solute concentration
Osmophiles
Bacterial growth
The primary way how bacterial divide, in which they produces two clone cells
Binary fission
Bacterial growth
Phases:
Generation time
Doubling time
Growth curve
Four phase
Lag phase
Log phase
Stationary phase
Death phase
Growth curve
Bacterias are preparing to divide
Nutrients > toxic products
Lag phase
Growth curve
Bacteria divide logarithmically
Log phase
Growth curve
Nutrients start to diminish
Toxic products start to accumulate
Cell replication=cell death
Cell variability starts to decrease
Stationary phase
Growth curve
Cell replication < cell death
Toxic products < nutrients
20-24 hrs
Death phase
Bacterial metabolism
Major pathway of glucose - pyruvate
Embden-Meyerhof parnas glycolytic pathway
