BACTERIAL CULTIVATION Flashcards
Refers to the increase in the number of bacteria rather
than in size
Bacterial Growth
Bacteria grows in ________ not in _________.
number ; size
BACTERIAL GROWTH REQUIREMENTS
• Nutritional
• Environmental
Three major nutritional needs for bacterial growth
• Carbon
• Nitrogen
• Energy
- Needed for the synthesis of cellular
components/constituents - Represents almost 50% of the dry weight of the
bacterium
Carbon
In the form of ATP: to perform metabolic and
cellular functions
Energy Source
- Needed for the synthesis of proteins and nucleic
acids - Makes up 14% of the dry weight of the bacteria
Nitrogen
- Bacterial cell is _______ water
- Meaning, they are a sealed plate of moisture, so
humidity level should be _______.
70%
Bacteria can tolerate salt concentration below ______.
6%
certain bacteria that can survive
high salt concentration environment
halophilic/halophiles
HALOPHILIC BACTERIA
• Staphylococcus spp.
• Enterococcus spp.
• Vibrio spp. (except Vibrio cholerae and Vibrio mimicus)
• Bacillus spp.
refers to bacteria that are very difficult to grow
fastidious
It is also cqlled as X Factor and is a degradation product of hemoglobin (RBC)
Hemin/Hematin
meaning of NAD
Nicotinamine Adenine Dinucleotide
It is required by Haemophilus spp.
V Factor (Vitamins)
What are the 2 common types of culture media that has an X and V Factor?
• Chocolate Agar Plate
• Blood Agar Plate
It has lysed RBC as well as both X and V Factor
Chocolate Agar Plate (CAP)
What should be applied to CAP to inactivate NADase so only V Factor would be present?
physical method/heat
It has intact RBC and only has X Factor.
Blood Agar Plate (BAP)
True or False
Haemophilus spp. only requires V factor
False
This culture is used in cultivating Haemophilus spp. because it has beta hemolysin that can liberate the V Factor.
Staphylococcus aureus
Sources of Blood
• 5% defribinated sheep’s blood
• Horse’s blood
• Rabbit’s blood
• Human blood (Type O)
Bacteria that grow, live, and survive in
the presence of oxygen
Aerobe
Absolutely requires oxygen to
grown, live, and survive
Strict/Obligate Aerobe
Examples of Strict/Obligate Aerobe Bacteria
• Micrococcus spp.
• Mycobacterium spp.
• Pseudomonas spp.
• Neisseria spp.
• Brucella spp.
• Francisella spp.
• Bordetella spp.
• Leptospira spp.
Bacteria that have the ability to grow, live and survive in small concentration of oxygen environment
Facultative Anaerobe
Examples of Facultative Anaerobe Bacteria
• Staphylococcus spp.
• Streptococcus spp.
• Family Enterobacteriaceae
Bacteria that prefers small concentration of oxygen environment approximately 2%-10%
Microaerophilic
Examples of Microaerophilic Bacteria
• Campylobacter spp.
• Helicobacter spp.
• Arcobacter spp.
• some Streptococcus spp.
Usually, we have ________ of oxygen available in the environment.
18%
Bacteria that grow, live, and survive in the absence of oxygen
Anaerobe
Absolutely do not require oxygen to grow, live, and survive
Strict/Obligate Anaerobe
Examples of Strict/Obligate Anaerobe
• many Clostridium spp. such as Clostridium noyvi
• Bacteroides spp.
• Fusobacterium spp.
• Peptostreptococcus spp.
• Porphyromonas spp.
Bacteria that do not require oxygen but may tolerate or withstand limited exposure to oxygen
Aerotolerant Anaerobe
Examples of Aerotolerant Anaerobe Bacteria
• some Clostridium spp. such as Clostridium perfringens
• Bacteroides fragilis
• most strains of Proprionibacterium and Lactobacillus
Bacteria that requires 5%-10% CO2
to grow
Capnophilic/Capnophiles
Examples of Capnophilic Bacteria
NHACEK GROUP
• Neisseria spp.
• Haemophilus spp.
• Aggregatibacter spp.
• Cardiobacterium spp.
• Eikenella spp.
• Kingella spp.
• Streptococcus pneumoniae
Most pathogenic bacteria would grow at
temperature between _______
35 - 37°C
Optimally growing between 20-40°C
Mesophilic
Growing optimally between 0-20°C
Psychrophilic/Cryophilic
Growing between 50-60°C
Thermophilic
Growing between 80-110°C; spore-forming bacteria
Hyperthermiphilic/Extremely Thermophilic
Wide range of temperature
Eurithermophilic
Narrow range of temperature
Sternothermophilic
What is the pH requirement needed by most bacteria to grow?
pH 7.0 - 7.5 (neutral or slightly alkaline environment)
Acid-loving bacteria
acidophilic (Lactobacillus acidophilus)
Alkali-loving bacteria
alkaliphilic (Gardnerella vaginalis)
loves high osmotic pressure
osmophilic (Archaebacteria spp.)
Refers to the stages of bacterial growth.
Bacterial Growth Phase
Bacteria are replicating via ________
binary fission (asexual reproduction)
______ refers to the duration or time of bacterial growth while _____ refers to the logarithm of viable cells
X-axis; Y-axis
It is the time required for 1 cellto divide into 2 cells.
Generation/doubling time
What is the generation time of E. coli?
20 mins.
What is the generation time of Mycobacterium tuberculosis?
24 hrs.
A phase where synthesis of proteins and DNA is already happening but cell division isn’t happening yet
Lag phase
The phase where bacteria is the most metabolically active; susceptible to anti-microbial agents
Logarithmic Growth Phase
Toxins are produced that are harmful to microorganisms
rate of cell division = rate of cell deaths
Stationary or Plateau phase
Bacterial growth failed to happen because the number of dead cells are greater than viable cells
Decline phase (Death)
It mimics the environment and nutrition that is originally in the reservoir
Culture Media
An artificial preparation in the laboratory which contains basic foundation of nutrients and a solidifying agent (if needed) to support the growth of microorganisms
Culture Media
Noun: growth of microorganism
Verb: to grow or to cultivate microorganism
Culture
Introducing the microorganism to the culture media
Inoculate/Plant/Cultivate
subsequent transfer of microorganisms from one culture media to another
Transplant/Subculture
Classification of Culture Media According to Composition
• SYNTHETIC/CHEMICALLY DEFINED
• NON
-SYNTHETIC/NON
-CHEMICALLY DEFINED COMPLEX
• TISSUE CULTURE
MEDIA
Composed of known and exact amounts of pure chemical substances; commonly used for culturing autotrophic microorganisms
SYNTHETIC/CHEMICALLY DEFINED
Composed of complex materials that are rich in vitamins and nutrients that are not usually represented by a chemical formula such as peptones, beef or yeast extract, plant extracts etc.
NON-SYNTHETIC/NON-CHEMICALLY DEFINED/COMPLEX
Live cells harvested from organs of humans and animals that supports the growth of obligate intracellular organisms that cannot grow in artificially prepared culture media.
TISSUE CULTURE MEDIA
source: kidney cells of an African Green Monkey
Vero Cell Line
source: mouse cell line
Mc Coy Cell Line
source: fertilized chicken eggs
Chicken Embryo
source: human lung carcinoma
A549 Cells
source: human cetvical carcinoma
HELA Cell Line
source: human epithelial cells of larynx carcinoma
Hep-2 Cell Line
Classification of Culture Media According to Physical State or Consistency
• Liquid
• Semi-Solid
• Solid
a culture medium that doesn’t contain a solidifying agent; dissolved in water
Liquid
A culture medium that contains 0.5% - 1%
agar
Semi-Solid
Used for observation of hydrogen sulfide gas production, indole production and motility
Sulfide Indole Motility (SIM) Medium
A culture medium which contains 1.5% - 3%T (2%-3% in other books) agar
Solid
Classification of Culture Media According to Manner of Dispensing/Formation
• Plated
• Tubed
• Bottled
Usually contained in a container that can be made of glass (pyrex) or disposable plastic (standard:100 mm in terms of diameter) (AST: 150mm)
Plated
Usually, container in glass tubes such as Wassermann tubes with different volume capacity (3mL, 5mL, 10mL) or in a tube with a flat bottom and a screw cap
Tubed
Culture media contained in a glass bottle that is usually used for blood culture
Bottled
Classification of Culture Media According to Function/Use
• GENERAL PURPOSE/PRIMARY/ BASIC/BASAL/SUPPORTIVE/GENERAL ISOLATION CULTURE MEDIA
•ENRICHED CULTURE MEDIA
• ENRICHMENT BROTH
Contains basic nutritional requirements to support the growth of non-fastidious microorganisms
• General Pirpose/Primary/Basic/Basal/Supportive/General Isolation Culture Media
Contains the basic nutritional requirement to support the growth of non-fastidious microorganisms with additives [special requirements: blood], enriching substances, or supplements to support the growth of fastidious microorganisms
Enriched Culture Media
A primary media used to support or favor the selective growth of pathogens in a specimen, such as stool or sputum, where the number of normal flora outnumber the pathogens
Enrichment Broth