Podcast
Questions and Answers
What is a commensal?
What is a commensal?
A resident of the skin that derives a benefit but does not harm us.
What does transient refer to in microbiology?
What does transient refer to in microbiology?
A microbe that comes in contact with the skin but is not a resident.
What does pathogenic mean?
What does pathogenic mean?
Ability to cause disease or infection.
What is the role of the coagulase enzyme?
What is the role of the coagulase enzyme?
Signup and view all the answers
Only S. aureus is coagulase positive.
Only S. aureus is coagulase positive.
Signup and view all the answers
What is meant by pure culture?
What is meant by pure culture?
Signup and view all the answers
What does 'sp.' stand for?
What does 'sp.' stand for?
Signup and view all the answers
What is fermentation?
What is fermentation?
Signup and view all the answers
Which of the following microbes can be seen using the light microscope (max magnification of x1000)? (Select all that apply)
Which of the following microbes can be seen using the light microscope (max magnification of x1000)? (Select all that apply)
Signup and view all the answers
Why is MSA used to cultivate skin microbes? (Select all that apply)
Why is MSA used to cultivate skin microbes? (Select all that apply)
Signup and view all the answers
Which method is used as a point of differentiation in MSA?
Which method is used as a point of differentiation in MSA?
Signup and view all the answers
MSA contains a high concentration of salt to mimic skin conditions.
MSA contains a high concentration of salt to mimic skin conditions.
Signup and view all the answers
What is used to differentiate skin microbes in MSA?
What is used to differentiate skin microbes in MSA?
Signup and view all the answers
There is a high concentration of sugar in MSA.
There is a high concentration of sugar in MSA.
Signup and view all the answers
The type of media, ie MSA and TBA, used for the skin swabs, are referred to as?
The type of media, ie MSA and TBA, used for the skin swabs, are referred to as?
Signup and view all the answers
What is the purpose of using the MEA plates for the skin swabs? (Select all that apply)
What is the purpose of using the MEA plates for the skin swabs? (Select all that apply)
Signup and view all the answers
It is possible to determine the genus and species of the microbes on these plates by looking at their colony morphology.
It is possible to determine the genus and species of the microbes on these plates by looking at their colony morphology.
Signup and view all the answers
Les porteurs de S. aureus représentent environ 50% de la population.
Les porteurs de S. aureus représentent environ 50% de la population.
Signup and view all the answers
What is one role of normal flora in the body?
What is one role of normal flora in the body?
Signup and view all the answers
Normal flora assists in phagocytosis.
Normal flora assists in phagocytosis.
Signup and view all the answers
How does normal flora protect the host against pathogens?
How does normal flora protect the host against pathogens?
Signup and view all the answers
In which areas does normal flora change the pH for protection?
In which areas does normal flora change the pH for protection?
Signup and view all the answers
Babies develop their microbiome while growing in utero.
Babies develop their microbiome while growing in utero.
Signup and view all the answers
A baby acquires their microbiome from the birth canal and also from breast or bottle milk and family members.
A baby acquires their microbiome from the birth canal and also from breast or bottle milk and family members.
Signup and view all the answers
Which of the following is true about the composition of the microflora of babies and toddlers?
Which of the following is true about the composition of the microflora of babies and toddlers?
Signup and view all the answers
The area of the body that has more fungi as normal flora is the foot.
The area of the body that has more fungi as normal flora is the foot.
Signup and view all the answers
S.epidermidis is a commensal of the skin but can be a serious opportunistic pathogen.
S.epidermidis is a commensal of the skin but can be a serious opportunistic pathogen.
Signup and view all the answers
What is the incidence of Propionibacterium acnes (cause of acne) and S.aureus?
What is the incidence of Propionibacterium acnes (cause of acne) and S.aureus?
Signup and view all the answers
The use of serology for diagnostic testing has helped microbiologists develop rapid highly specific test kits using antibodies and latex beads to detect bacterial antigens.
The use of serology for diagnostic testing has helped microbiologists develop rapid highly specific test kits using antibodies and latex beads to detect bacterial antigens.
Signup and view all the answers
Which of the following bacterial structures can be observed with light microscopy? (Select all that apply)
Which of the following bacterial structures can be observed with light microscopy? (Select all that apply)
Signup and view all the answers
Endospores stain easily with the Gram stain.
Endospores stain easily with the Gram stain.
Signup and view all the answers
What are capsules in bacteria?
What are capsules in bacteria?
Signup and view all the answers
What type of genetic material do plasmids contain?
What type of genetic material do plasmids contain?
Signup and view all the answers
Which of the following are examples of serological tests? (Select all that apply)
Which of the following are examples of serological tests? (Select all that apply)
Signup and view all the answers
PCR has been developed for rapid identification of a range of microbes including bacteria, fungi and viruses.
PCR has been developed for rapid identification of a range of microbes including bacteria, fungi and viruses.
Signup and view all the answers
PCR requires the use of primers. Without these, there is no PCR reaction.
PCR requires the use of primers. Without these, there is no PCR reaction.
Signup and view all the answers
Study Notes
Important Microbial Terms
- Commensal: Microbes that reside on the skin; they benefit from the host without causing harm.
- Transient: Temporary microbes that come in contact with the skin but do not establish a permanent presence.
- Pathogenic: Refers to the capacity of an organism to cause disease or infection in a host.
- Coagulase Negative: These bacteria do not produce the coagulase enzyme, which is primarily associated with Staphylococcus aureus (coagulase positive). Non-pathogenic Staphylococcus species are typically coagulase negative.
- Pure Culture: A laboratory culture that contains only one type of microbe, ensuring uniformity for study or experimentation.
- sp.: Abbreviation for "species," often used when the specific species is not identified.
- Fermentation: A metabolic process where sugar is converted into acids, gases, or alcohol under anaerobic conditions (absence of oxygen).
MSA (Mannitol Salt Agar) Cultivation
- MSA contains a high concentration of salt, creating hypertonic conditions that favor the growth of halophilic (salt-loving) skin microbes while inhibiting most other bacteria.
- Mannitol fermentation serves as a metabolic indicator, distinguishing between mannitol-fermenting bacteria (which will produce acid and change the color of the medium) and non-fermenters.
- Lactose fermentation is often mentioned in context but is not a primary function of MSA; it is more relevant for other selective media types.
- High sugar concentration in MSA primarily comes from mannitol, which provides an energy source for bacteria capable of fermentation, promoting acid production and visual differentiation.
MSA (Mannitol Salt Agar) in Skin Microbe Cultivation
- Lactose fermentation serves as a differentiating factor for identifying specific microbe types within the culture.
- The agar contains a high concentration of salt, which simulates the osmotic conditions found on human skin, supporting the growth of skin-associated microorganisms.
- Mannitol fermentation is another key aspect that distinguishes bacteria; organisms that can ferment mannitol produce acids that change the agar's coloration.
- An elevated level of sugar is incorporated in the medium, providing a nutrient source specifically beneficial for bacteria adapted to skin environments.
Microbial Terminology
- Commensal: Microbes that are natural residents of the skin, benefiting from the host without causing harm.
- Transient: Microbes that briefly contact the skin but do not establish residency.
- Pathogenic: Describes organisms capable of causing disease or infection in the host.
- Coagulase Negative: Refers to non-pathogenic species of Staphylococcus without the coagulase enzyme, which is predominantly present in S. aureus.
- Pure Culture: Contains only one species or strain of microbe, essential for studying specific microorganisms.
- sp.: Abbreviation indicating an unspecified species within a genus.
- Fermentation: The metabolic process where sugar is converted into acids or alcohol under anaerobic conditions (absence of oxygen).
Microscopy and Microbial Visualization
- Light Microscope Capability: Can visualize protozoa, yeast cells, bacteria, and fungal hyphae with a maximum magnification of x1000.
- Viruses are too small to be seen with a light microscope at this magnification.
MSA (Mannitol Salt Agar) Usage
- Lactose Fermentation: Helps differentiate between microbial species based on their ability to ferment lactose.
- High Salt Concentration: Mimics skin conditions and helps select for skin-associated microbes.
- Mannitol Fermentation: Serves as another differentiation point for identifying microbial species’ fermentation capabilities.
- Sugar Concentration: Supports the growth of certain bacteria requiring higher sugar levels.
Types of Media
- Selective Media: Designed to favor the growth of specific microorganisms while inhibiting others.
- Differential Media: Allows identification of microorganisms based on their characteristics when grown on the medium.
- Enriched Media: Contains nutrients that enhance the growth of particular microbes.
- Selective and Differential Media: Combines both selective and differential media properties, as seen with MSA and TBA used for skin swabs.
MEA Plates Purpose
- MEA plates stand for Malt Extract Agar plates, primarily designed for cultivating fungi and yeasts.
- Serve as an all-purpose medium, making them suitable for the growth of various bacteria alongside yeasts.
- Particularly effective for isolating and growing Staphylococcus species, which are commonly found on the skin and are important for clinical diagnostics.
Microbial Terms
- Commensal: Microbes that inhabit the skin without causing harm; they benefit from the host.
- Transient: Microbes that briefly contact the skin without establishing residency.
- Pathogenic: Refers to microbes that have the ability to cause disease or infection.
- Coagulase Negative: Refers to bacteria that do not produce the coagulase enzyme; most are non-pathogenic and include Staphylococcus species other than S.aureus.
- Pure Culture: A laboratory culture consisting of a single species or strain of microbe.
- sp.: Used to denote an unspecified species within a genus.
- Fermentation: The metabolic process of converting sugars into energy under anaerobic conditions (absence of oxygen).
Microscopy
- Microbes visible under a light microscope (maximum magnification of x1000) include:
- Protozoa
- Yeast cells
- Bacteria
- Fungal hyphae
- Viruses cannot be observed with this microscope.
MSA (Mannitol Salt Agar) Usage
- MSA is used for cultivating skin microbes due to:
- Lactose fermentation as a differentiating factor.
- High salt concentration mimicking skin conditions for microbial growth.
- Mannitol fermentation as an additional point of differentiation.
- A high sugar concentration supports bacterial growth.
Media Types
- MSA and TBA used for skin swabs are classified as:
- Selective and differential media.
MEA (Malt Extract Agar) Plates
- MEA plates are utilized to:
- Grow fungi and yeasts.
- Serve as an all-purpose medium for bacterial and yeast growth.
- Support the growth of Staphylococcus species.
Colony Morphology
- It is possible to identify the genus and species of microbes on culture plates by examining their colony morphology.
Carrier Statistics
- Approximately 50% of the population are carriers of S.aureus, but this statement is false.
Role of Normal Flora in the Body
- Normal flora contributes to the host’s defense by altering pH levels in areas like the skin and urogenital tract, creating an unfavorable environment for pathogenic microorganisms.
- These microorganisms assist in phagocytosis, enhancing the immune response by enabling the body's cells to engulf and remove harmful invaders.
- Normal flora plays a vital role in synthesizing key nutrients, including certain vitamins, which are essential for various bodily functions.
- They provide protective benefits against potential pathogens by occupying binding sites on mucosal membranes, thereby preventing pathogen colonization and infection.
Important Microbial Terms
- Commensal: Microorganisms that reside on the skin, providing benefits without causing harm.
- Transient: Microbes that temporarily contact the skin but do not establish residence.
- Pathogenic: Refers to microorganisms with the capability to cause disease or infection.
- Coagulase Negative: Describes bacteria lacking the coagulase enzyme, which forms fibrin clots; mostly seen in non-pathogenic Staphylococcus species.
- Pure Culture: A laboratory culture containing a single microbial species or strain.
- sp.: Indicates an unidentified species within microbial classification.
- Fermentation: The process of utilizing sugar in the absence of oxygen (anaerobic conditions).
Microbes Visible Under Light Microscope
- Protozoa, Yeast Cells, Bacteria, Fungal Hyphae: All can be observed using a light microscope with a maximum magnification of x1000.
- Viruses: Too small to be resolved by a light microscope.
MSA Utilization for Cultivating Skin Microbes
- Lactose Fermentation: Serves as a differentiation point for microbial identification.
- High Salt Concentration: Mimics skin conditions, creating a selective environment.
- Mannitol Fermentation: Another key differentiation point aiding in microbial identification.
- Sugar Concentration: Supports growth by providing a nutrient source for bacteria.
Media Types Used for Skin Swabs
- Selective Media: Used to favor certain microbes while inhibiting others.
- Differential Media: Allows differentiation between microbial species based on growth characteristics.
Purpose of MEA Plates for Skin Swabs
- Primarily designed to grow fungi and yeasts.
- It is considered an all-purpose medium for the growth of various microbes, including bacteria.
Determining Microbial Genus and Species
- It is indeed possible to ascertain the genus and species of microbes based on their colony morphology observed on MEA plates.
Carriers of S.aureus
- Approximately 50% of the population are carriers, but this statement is False.
Role of Normal Flora in the Body
- Protection: Normal flora alters pH in areas like skin and urogenital tracts, providing protection against pathogens.
- Assistance with Phagocytosis: Contributes to immune system function.
- Nutritional Contribution: Some flora produce vitamins beneficial to the host.
- Occupying Mucosal Membranes: Shields the host from pathogen attachment through competitive exclusion.
Development of Microbiome in Babies
- It is True that babies begin developing their microbiome while growing in utero.
Important Microbial Terms
- Commensal: Microbes that reside on the skin, benefiting from the host without causing harm.
- Transient: Microbes that temporarily contact the skin but do not establish residence.
- Pathogenic: Microbes capable of causing disease or infection.
- Coagulase negative: Refers to bacteria, primarily Staphylococcus species, that do not produce the coagulase enzyme, unlike pathogenic S. aureus.
- Pure culture: A culture consisting solely of one species or strain of microbe.
- sp.: Abbreviation for species, indicating an unknown species.
- Fermentation: The process of utilizing sugar in the absence of oxygen, leading to energy production.
Microbes Visible Under Light Microscope
- Protozoa and yeast cells can be observed using a light microscope with maximum magnification of x1000.
- Bacteria, fungal hyphae, but not viruses are also visible under these conditions.
MSA for Cultivating Skin Microbes
- MSA (Mannitol Salt Agar) is used to cultivate skin microbes because:
- It contains high salt concentrations to simulate skin conditions.
- Mannitol fermentation serves as a differentiation point for identifying specific microbes.
- Lactose fermentation helps differentiate bacterial types.
Media Types for Skin Swabs
- MSA and TBA are classified as selective and differential media, promoting growth of specific organisms while inhibiting others.
Purpose of MEA Plates
- MEA (Malt Extract Agar) plates are designed for growing fungi and yeasts.
- They can also support a wide range of bacteria alongside yeasts.
Determining Microbial Taxonomy
- The genus and species of microbes on MEA plates can be identified by examining their colony morphology.
Carriers of S.aureus
- Approximately 50% of the population does not act as carriers for S. aureus.
Role of Normal Flora
- Normal flora provides several benefits, including:
- Protection of the host by altering pH in areas like skin and the urogenital tract.
- Assisting with phagocytosis.
- Supplying essential vitamins to the host.
- Protecting against pathogens by occupying mucosal membrane sites.
Development of Microbiome in Babies
- Babies do not develop their microbiome while in utero; they acquire it through exposure during birth, breastfeeding, and interaction with family members.
Important Microbial Terms
- Commensal: Microbes that reside on the skin, benefiting from the host without causing harm.
- Transient: Microbes that temporarily contact the skin but do not establish residence.
- Pathogenic: Microbes capable of causing disease or infection.
- Coagulase negative: Refers to bacteria, primarily Staphylococcus species, that do not produce the coagulase enzyme, unlike pathogenic S. aureus.
- Pure culture: A culture consisting solely of one species or strain of microbe.
- sp.: Abbreviation for species, indicating an unknown species.
- Fermentation: The process of utilizing sugar in the absence of oxygen, leading to energy production.
Microbes Visible Under Light Microscope
- Protozoa and yeast cells can be observed using a light microscope with maximum magnification of x1000.
- Bacteria, fungal hyphae, but not viruses are also visible under these conditions.
MSA for Cultivating Skin Microbes
- MSA (Mannitol Salt Agar) is used to cultivate skin microbes because:
- It contains high salt concentrations to simulate skin conditions.
- Mannitol fermentation serves as a differentiation point for identifying specific microbes.
- Lactose fermentation helps differentiate bacterial types.
Media Types for Skin Swabs
- MSA and TBA are classified as selective and differential media, promoting growth of specific organisms while inhibiting others.
Purpose of MEA Plates
- MEA (Malt Extract Agar) plates are designed for growing fungi and yeasts.
- They can also support a wide range of bacteria alongside yeasts.
Determining Microbial Taxonomy
- The genus and species of microbes on MEA plates can be identified by examining their colony morphology.
Carriers of S.aureus
- Approximately 50% of the population does not act as carriers for S. aureus.
Role of Normal Flora
- Normal flora provides several benefits, including:
- Protection of the host by altering pH in areas like skin and the urogenital tract.
- Assisting with phagocytosis.
- Supplying essential vitamins to the host.
- Protecting against pathogens by occupying mucosal membrane sites.
Development of Microbiome in Babies
- Babies do not develop their microbiome while in utero; they acquire it through exposure during birth, breastfeeding, and interaction with family members.
Microflora Composition in Babies and Toddlers
- At 1 month old, babies predominantly have Bifidobacterium, a beneficial bacteria essential for gut health.
- The composition of gut microflora shifts between 1 month and 2-3 years of age.
- By the age of 2-3 years, Lactobacilli become more prevalent in the gut microbiome, indicating a transition in the gut environment.
- The presence of Enterobacteriaceae is prominent in babies at 1 month but declines over time.
- By the age of 2-3 years, there is a notable increase in Bifidobacterium, highlighting its importance as children develop.
Important Microbial Terms
- Commensal: Microbes that reside on the skin, benefiting from it without causing harm.
- Transient: Microbes that come into contact with the skin but do not establish residence.
- Pathogenic: Refers to microbes that possess the ability to cause disease or infection.
- Coagulase Negative: Typically non-pathogenic Staphylococcus species, distinguishable by their lack of the coagulase enzyme, unlike S. aureus, which is coagulase positive.
- Pure Culture: A culture that contains only one type of microbe, representing a single species or strain.
- sp.: Abbreviation indicating an unknown species.
- Fermentation: The process whereby sugar is utilized under anaerobic conditions (absence of oxygen).
Microbes Observed with Light Microscope
- Microbes visible at a maximum magnification of x1000:
- Protozoa
- Yeast Cells
- Bacteria
- Fungal Hyphae
- Viruses are not observable with this microscope.
MSA (Mannitol Salt Agar) Usage
- MSA is utilized for cultivating skin microbes due to:
- Lactose fermentation, which aids in microbial differentiation.
- High salt concentration, mimicking skin conditions.
- Mannitol fermentation, providing further differentiation.
- Nutrient-rich environment due to higher sugar concentration for bacterial growth.
Types of Media for Skin Swabs
- MSA and TBA used for skin swabs are categorized as:
- Selective and differential media, designed to allow the growth of specific microbes while inhibiting others.
MEA Plates for Skin Swabs
- MEA (Malt Extract Agar) plates serve several purposes:
- Specifically used for growing fungi and yeasts.
- Function as an all-purpose medium for bacteria and yeasts.
- May be useful for growing Staphylococcus species.
Microbial Identification
- The genus and species of microbes on MEA plates can be determined by observing colony morphology, which refers to macroscopic characteristics.
Carrier Status of S. aureus
- Approximately 50% of the population are carriers of S. aureus is false.
Role of Normal Flora in the Body
- Normal flora serve various protective roles including:
- Modifying pH levels in areas such as the skin and urogenital tract.
- Assisting in phagocytosis.
- Contributing essential factors like vitamins.
- Competing with pathogens for binding sites on mucosal membranes, thus providing protection.
Microbiome Development in Babies
- Babies develop their microbiome primarily after birth rather than while in utero.
- They acquire their microbiome through the birth canal and via breast or bottle milk, as well as contact with family members.
Microflora Composition in Infants
- At 1 month, infants primarily have Bifidobacterium; by ages 2-3 years, there is an increase in Lactobacilli.
- Infant microflora transitions from a predominance of Enterobacteriaceae at 1 month to more Bifidobacterium by ages 2-3 years.
Normal Flora of Skin
- Propionibacterium acnes is the primary bacterium associated with acne and can have an incidence ranging from 45% to 100% among individuals.
- Staphylococcus aureus (S.aureus) shows a much lower incidence, ranging from 0% to 25% in the general population.
- Risk factors and individual skin conditions can greatly influence the presence of these bacteria on the skin.
- Propionibacterium acnes contributes to acne lesions through its metabolic activities and interaction with the immune system.
- S.aureus is commonly known for skin infections, but its prevalence is less frequent as a normal skin flora compared to Propionibacterium acnes.
Serology in Diagnostic Testing
- Serology utilizes antibodies to identify the presence of specific antigens related to bacterial cells.
- Diagnostic testing through serology enables microbiologists to create rapid and highly specific test kits.
- These test kits often employ latex beads, which enhance the visibility of reactions when bacterial antigens are present.
- The specificity of these tests increases the accuracy of diagnoses in bacterial infections.
- Rapid testing contributes to timely treatment decisions in clinical settings.
Microbial Terms
- Commensal: Microbes residing on the skin that benefit without causing harm.
- Transient: Temporary microbes that contact the skin but do not establish residence.
- Pathogenic: Refers to the ability of a microbe to cause disease or infection.
- Coagulase Negative: Non-pathogenic Staphylococcus species; only S. aureus tests positive for coagulase.
- Pure Culture: Contains only one type of microbe (species or strain).
- sp.: Abbreviation for species when the specific type is unknown.
- Fermentation: Process of sugar utilization without oxygen (anaerobic conditions).
Light Microscope Visibility
- Can visualize:
- Protozoa
- Yeast cells
- Bacteria
- Fungal hyphae
- Cannot visualize viruses using a light microscope.
MSA for Cultivating Skin Microbes
- MSA (Mannitol Salt Agar) serves to differentiate microbes based on:
- Lactose fermentation.
- High salt concentration mimicking skin conditions.
- Mannitol fermentation.
- High sugar concentration for microbial growth.
Types of Media
- MSA and TBA used for skin swabs are categorized as:
- Selective media.
- Differential media.
MEA Plates for Skin Swabs
- MEA (Malt Extract Agar) is used to grow:
- Fungi and yeasts.
- It is an all-purpose medium for various bacteria and yeasts.
Determining Microbe Species
- Genus and species identification can be achieved through colony morphology (macroscopic features).
Normal Flora and Health
- Normal flora roles:
- Protect host by altering pH in areas like skin and urogenital tract.
- Contribute to immune responses like phagocytosis.
- Supply important factors (e.g., vitamins) to the host.
- Occupy mucosal membrane sites to prevent pathogen colonization.
Microbiome Development in Babies
- Babies develop their microbiome primarily from:
- Birth canal and breast/bottle milk.
- Interactions with family members.
- Composition changes over time:
- At 1 month, predominantly Bifidobacterium.
- Transition to more Lactobacilli by ages 2-3.
Normal Flora Composition Changes
- Foot area has a higher concentration of fungi among normal flora.
- S. epidermidis is a skin commensal that can act as an opportunistic pathogen.
Acne-Causing Microbes
- Incidence rates:
- Propionibacterium acnes (causes acne): 45-100%.
- S. aureus: 0-25%.
Microbial Terms
- Commensal: Microbes residing on the skin that benefit without harming the host.
- Transient: Temporary microbes that contact the skin but aren't permanent residents.
- Pathogenic: Microbes capable of causing disease.
- Coagulase Negative: Refers to non-pathogenic species; typically, S. aureus is coagulase positive.
- Pure Culture: A culture containing only one microbial species or strain.
- sp.: Abbreviation indicating an unidentified species.
- Fermentation: Process of sugar utilization in anaerobic conditions.
Light Microscope Visibility
- Microbes visible under a light microscope (maximum magnification x1000) include protozoa, yeast cells, bacteria, and fungal hyphae. Viruses cannot be observed at this magnification.
MSA Usage for Skin Microbes
- MSA (Mannitol Salt Agar) facilitates skin microbe cultivation due to:
- High salt concentration simulating skin conditions.
- Mannitol fermentation serving as a differentiation point for microbes.
- Lactose fermentation is mentioned but not directly applied in the context of skin microbes.
Media Types for Skin Swabs
- MSA and TBA are categorized as selective and differential media, allowing for the growth of specific microflora.
MEA Plates Purpose
- MEA (Malt Extract Agar) plates are utilized for cultivating fungi and yeasts, serving as an all-purpose medium for bacteria and yeasts.
Microbial Identification
- Genus and species of microbes can be determined by observing colony morphology—true statement.
Carriers of S. aureus
- Approximately 50% of the population are carriers of S. aureus—false statement.
Role of Normal Flora
- Normal flora provide protection by:
- Altering pH levels in certain body areas.
- Assisting with phagocytosis.
- Contributing essential factors like vitamins.
- Occupying mucosal membrane sites to prevent pathogen colonization.
Microbiome Development in Babies
- Babies develop their microbiome post-birth, not while in utero—true statement.
- Source of microbiome includes birth canal exposure and breast or bottle milk.
Composition of Microflora in Children
- At 1 month, babies predominantly harbor Bifidobacterium. By ages 2-3, Lactobacilli become more prevalent.
- Enterobacteriaceae is mainly present at 1 month, decreasing in favor of Bifidobacterium by ages 2-3.
True Statements
- The foot area has a higher presence of fungi as normal flora—false statement regarding its specificity.
- S. epidermidis serves as a skin commensal but can act as an opportunistic pathogen—true statement.
Prevalence of Specific Microbes
-
Incidence of Propionibacterium acnes and S. aureus:
- 45-100% prevalence for Propionibacterium.
- 0-25% prevalence for S. aureus—correct statistic.
Serology in Diagnostics
- Serology has advanced diagnostic testing, enabling rapid detection of bacterial antigens using antibodies and latex beads—true statement.
Bacterial Structures Observable with Light Microscopy
- Capsules: Composed of polysaccharides, these external layers protect bacteria from phagocytosis and help in attachment to surfaces.
- Flagella: Specialized appendages for motility, often detected using specific staining techniques that make them visible under light microscopy.
- Endospores: Highly resistant structures formed by certain bacteria, they do not react to Gram staining, appearing clear within the bacterial cell and can survive extreme conditions.
- Plasmids: Small, circular pieces of DNA that are separate from the chromosomal DNA, often responsible for carrying genes that confer antibiotic resistance or other advantageous traits.
Important Microbial Terms
- Commensal: Microbes that benefit from living on skin without harming the host.
- Transient: Microbes that temporarily contact the skin without becoming residents.
- Pathogenic: Microbes capable of causing disease or infection.
- Coagulase Negative: Refers to Staphylococcus species lacking coagulase enzyme, typically less pathogenic.
- Pure Culture: A culture containing only one species or strain of microbe.
- sp.: Indicates an unspecified species.
- Fermentation: Process of using sugar in the absence of oxygen.
Microscopy and Microbe Visibility
- Light microscopy can effectively observe protozoa, yeast cells, bacteria, and fungal hyphae, but not viruses due to their smaller size.
MSA (Mannitol Salt Agar) Usage
- MSA is employed for culturing skin microbes due to its high salt concentration, simulating skin conditions.
- Mannitol fermentation serves as a point of differentiation in identifying microbial species.
Types of Media
- MSA is classified as selective and differential media, aiding in the growth and identification of specific bacteria.
MEA (Malt Extract Agar) Plates
- MEA plates are utilized to cultivate fungi and yeasts and can also support certain bacteria.
Microbiome Development
- Babies develop their microbiome primarily during birth and through breastfeeding, not in utero.
- 50% of the population are carriers of S.aureus, which could be misleading as not all individuals harbor this pathogen.
Normal Flora Roles
- Normal flora provides protection by altering pH, contributing vitamins, and occupying mucosal sites to defend against pathogenic invasion.
Microflora in Infants
- At one month, infants predominantly have Bifidobacterium, with a shift towards more Lactobacilli by age 2-3 years.
- The foot is recognized as a body area with a higher concentration of fungi in normal flora.
- Propionibacterium acnes incidence is 45-100% among individuals, while S.aureus presents a 0-25% occurrence.
Bacterial Structures in Light Microscopy
- Structures observable include capsules, flagella (with special stains), endospores, and plasmids.
Serological Testing
- Serological tests like the Staphytect Test kit, immunofluorescence, coagulase test, and hemolysis reactions help detect bacterial antigens.
- PCR has been optimized for rapid microbial identification and requires primers to initiate the reaction.
Important Microbial Terms
- Commensal: Microbes that benefit from living on skin without harming the host.
- Transient: Microbes that temporarily contact the skin without becoming residents.
- Pathogenic: Microbes capable of causing disease or infection.
- Coagulase Negative: Refers to Staphylococcus species lacking coagulase enzyme, typically less pathogenic.
- Pure Culture: A culture containing only one species or strain of microbe.
- sp.: Indicates an unspecified species.
- Fermentation: Process of using sugar in the absence of oxygen.
Microscopy and Microbe Visibility
- Light microscopy can effectively observe protozoa, yeast cells, bacteria, and fungal hyphae, but not viruses due to their smaller size.
MSA (Mannitol Salt Agar) Usage
- MSA is employed for culturing skin microbes due to its high salt concentration, simulating skin conditions.
- Mannitol fermentation serves as a point of differentiation in identifying microbial species.
Types of Media
- MSA is classified as selective and differential media, aiding in the growth and identification of specific bacteria.
MEA (Malt Extract Agar) Plates
- MEA plates are utilized to cultivate fungi and yeasts and can also support certain bacteria.
Microbiome Development
- Babies develop their microbiome primarily during birth and through breastfeeding, not in utero.
- 50% of the population are carriers of S.aureus, which could be misleading as not all individuals harbor this pathogen.
Normal Flora Roles
- Normal flora provides protection by altering pH, contributing vitamins, and occupying mucosal sites to defend against pathogenic invasion.
Microflora in Infants
- At one month, infants predominantly have Bifidobacterium, with a shift towards more Lactobacilli by age 2-3 years.
- The foot is recognized as a body area with a higher concentration of fungi in normal flora.
- Propionibacterium acnes incidence is 45-100% among individuals, while S.aureus presents a 0-25% occurrence.
Bacterial Structures in Light Microscopy
- Structures observable include capsules, flagella (with special stains), endospores, and plasmids.
Serological Testing
- Serological tests like the Staphytect Test kit, immunofluorescence, coagulase test, and hemolysis reactions help detect bacterial antigens.
- PCR has been optimized for rapid microbial identification and requires primers to initiate the reaction.
Important Microbial Terms
- Commensal: Microbes that benefit from living on skin without harming the host.
- Transient: Microbes that temporarily contact the skin without becoming residents.
- Pathogenic: Microbes capable of causing disease or infection.
- Coagulase Negative: Refers to Staphylococcus species lacking coagulase enzyme, typically less pathogenic.
- Pure Culture: A culture containing only one species or strain of microbe.
- sp.: Indicates an unspecified species.
- Fermentation: Process of using sugar in the absence of oxygen.
Microscopy and Microbe Visibility
- Light microscopy can effectively observe protozoa, yeast cells, bacteria, and fungal hyphae, but not viruses due to their smaller size.
MSA (Mannitol Salt Agar) Usage
- MSA is employed for culturing skin microbes due to its high salt concentration, simulating skin conditions.
- Mannitol fermentation serves as a point of differentiation in identifying microbial species.
Types of Media
- MSA is classified as selective and differential media, aiding in the growth and identification of specific bacteria.
MEA (Malt Extract Agar) Plates
- MEA plates are utilized to cultivate fungi and yeasts and can also support certain bacteria.
Microbiome Development
- Babies develop their microbiome primarily during birth and through breastfeeding, not in utero.
- 50% of the population are carriers of S.aureus, which could be misleading as not all individuals harbor this pathogen.
Normal Flora Roles
- Normal flora provides protection by altering pH, contributing vitamins, and occupying mucosal sites to defend against pathogenic invasion.
Microflora in Infants
- At one month, infants predominantly have Bifidobacterium, with a shift towards more Lactobacilli by age 2-3 years.
- The foot is recognized as a body area with a higher concentration of fungi in normal flora.
- Propionibacterium acnes incidence is 45-100% among individuals, while S.aureus presents a 0-25% occurrence.
Bacterial Structures in Light Microscopy
- Structures observable include capsules, flagella (with special stains), endospores, and plasmids.
Serological Testing
- Serological tests like the Staphytect Test kit, immunofluorescence, coagulase test, and hemolysis reactions help detect bacterial antigens.
- PCR has been optimized for rapid microbial identification and requires primers to initiate the reaction.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on important microbiological terms! This quiz covers concepts such as commensal, transient, and pathogenic microbes, along with details on coagulase negative bacteria and pure cultures. Perfect for students of microbiology or anyone interested in the subject.
