Microbial Ecology Flashcards by Khaidel Musahari

is the study of
microorganisms in their natural environments, focusing on their _________ with each other and their
surroundings.

Microbial ecology; interactons

How well did you know this?

Not at all

Perfectly

It encompasses various aspects, including microbial diversity, nutrient
cycling, symbiosis, and ecosystem stability.

Microbial ecology

How well did you know this?

Not at all

Perfectly

Microbial Diversity is composed of? (5)

Bacteria, Archaea, Fungi, Viruses, and Protists

How well did you know this?

Not at all

Perfectly

Classification of microbial diversity is based on _________, _________, and _________.

morphology, metabolism, and genetic traits

How well did you know this?

Not at all

Perfectly

What are the microbial habitats? (4)

Terrestrial ecosystems, Aquatic ecosystems, Extreme environments, and Human microbiome

How well did you know this?

Not at all

Perfectly

Examples of terrestrial ecosystems are? (2)

Soil microbiomes, rhizosphere interactions

How well did you know this?

Not at all

Perfectly

Examples of Aquatic ecosystems are? (2)

Freshwater and marine microbial communities

How well did you know this?

Not at all

Perfectly

Examples ofExtreme environments are? (4)

Thermophiles, halophiles, acidophiles, and psychrophiles

How well did you know this?

Not at all

Perfectly

These are extremophilic organisms that are capable of growth and reproduction in low temperatures, ranging from −20 °C to 20 °C.

Psychrophiles

How well did you know this?

Not at all

Perfectly

Two microbial Interactions (?)

Symbiotic relationships; competition and cooperation

How well did you know this?

Not at all

Perfectly

Examples of Symbiotic relationships (3)

Mutualism , Commensalism & Parasitism

How well did you know this?

Not at all

Perfectly

Examples of Competition and Cooperation interactions (3)

Resource competition, biofilm formation, & quorum sensing

How well did you know this?

Not at all

Perfectly

It is a cell-to-cell communication system where bacteria release signaling molecules (autoinducers) to sense their population density and coordinate their behavior, such as biofilm formation or virulence.

Quorum sensing

How well did you know this?

Not at all

Perfectly

Microbial Metabolism and Nutrient Cycling (4)

– Carbon Cycle
– Nitrogen Cycle
– Sulfur Cycle
– Phosphorus Cycle

How well did you know this?

Not at all

Perfectly

Methods used to Study Microbial Ecology (4)

Microbial Culture
Molecular and Genomic Approaches
Microscopy and
Imaging Techniques
Stable Isotope
Probing

How well did you know this?

Not at all

Perfectly

Examples of Microbial Culture (2)

Enrichment and selective media

How well did you know this?

Not at all

Perfectly

Is used to isolate a specific type of microorganism from a mixed population by inhibiting the growth of others.

Selective media

How well did you know this?

Not at all

Perfectly

Is used to increase the population density of a specific microorganism within a mixed population by providing favorable conditions for its growth while suppressing competitors.

Enrichment media

How well did you know this?

Not at all

Perfectly

Anaerobic
culturing is for?

oxygen-sensitive microbes

How well did you know this?

Not at all

Perfectly

Anaerobic jar is for?

Cultivation of anaerobic
bacteria

How well did you know this?

Not at all

Perfectly

The anaerobic jar contains envelopes of ______, _______, and an _______.

sodium bicarbonate; sodium borohydride; and Anaerobic indicator (methylene blue)

How well did you know this?

Not at all

Perfectly

Used for dentifying microbial diversity

16S rRNA sequencing

How well did you know this?

Not at all

Perfectly

Used for analyzing microbial communities
without culturing

Metagenomics

How well did you know this?

Not at all

Perfectly

used for understanding gene expression in microbial

Transcriptomics and proteomics

How well did you know this?

Not at all

Perfectly

Molecular and Genomic Approaches (3)

* 16S rRNA sequencing: * Metagenomics * Transcriptomics and proteomics

Microscopy and Imaging Techniques (2)

1. Fluorescence microscopy ( FISH - Fluorescence In Situ Hybridization) 2. Electron microscopy

Used for for ultrastructural studies

Electron microscopy

used for tracking nutrient utilization by specific microbes

Stable Isotope Probing

Applications of Microbial Ecology (3)

1. Environmental Biotechnology 2. Health and Medicine 3. Industrial Application

Environmental Biotechnologies (3)

1. Bioremediation 2. Wastewater treatment 3. Biofertilizers

Is the microbial degradation of pollutants(?)

Bioremediation

Role of microbes in sewage processing

Wastewater treatment

Enhances soil fertility with microbial inoculants (?)

Biofertilizers

Microbial Industrial Applications (2)

1. Fermentation technology 2. Synthetic biology

Characterized by microbial production of antibiotics, enzymes, and biofuels

Fermentation technology

Characterized by engineering of microbes for new applications

Synthetic biology

How does microbial diversity contribute to ecosystem resilience? (Familiarize)

1. Enhancing Nutrient Cycling 2. Promoting Stability in Changing Conditions 3. Supporting Plant Growth & Soil Health 4. Regulating Disease & Pathogen Control 5. Aiding Climate Change Adaptation 6. Supporting Food Webs & Biodiversity 7. Assisting in Ecosystem Recovery (Bioremediation)

The role of climate change in altering microbial communities (Familiarize) (6)

1. Rising Temperatures 2. Changes in Precipitation Patterns (Droughts & Floods) 3. Ocean Acidification & Warming 4. Melting Permafrost & Microbial Greenhouse Gas Release 5. Disrupting Soil Microbiomes & Agriculture 6. Shifting Microbial Pathogens & Disease Patterns

Both the host and microbe benefit (?)

Mutualism

Mutualism: ⎽⎽⎽⎽⎽⎽⎽⎽ , a gut bacterium, helps digest complex ⎽⎽⎽⎽⎽⎽⎽⎽ from plants, providing nutrients for the host while receiving a hospitable environment in return.

Bacteroides thetaiotaomicron; polysaccharides

One organism benefits while the other isunaffected

Commensalism

Commensalism: ⎽⎽⎽⎽⎽⎽⎽⎽ on human skin prevents colonization by harmful bacteria without affecting the host.

Staphylococcus epidermidis

The microbe harms the host (?)

Parasitism (Pathogenicity)

Parasitism: ⎽⎽⎽⎽⎽⎽⎽⎽, a bacterium found in the stomach, can cause gastric ulcers and cancer in some individuals .

Helicobacter pylori

________ train the immune system from infancy, helping it distinguish between pathogens and harmless microbes .

Gut microbiota

________ produces butyrate, which reduces gut inflammation and is protective against ________.

Faecalibacterium prausnitzii; inflammatory bowel diseases (IBD)

Beneficial bacteria produce ________ that regulate immune cell activity and prevent excessive inflammation

short- chain fatty acids (SCFAs)

Is characterized by microbial imbalance (?)

Dysbiosis

Dysbiosis can lead to? (2)

1. Autoimmune diseases 2. Allergies

Dysbiosis: Autoimmune diseases examples (2)

1. multiple sclerosis 2. type 1 diabetes

This is due to overactive immune responses .

Autoimmune diseases

This is due to reduced microbial diversity affecting immune tolerance .

Allergies

Dysbiosis: Allergies examples (2)

1. asthma 2. eczema

Gut microbiota synthesize essential vitamins (______, _____) and produce _____ that regulatemetabolism .

B vitamins, vitamin K; SCFAs

This enhances gut barrier function and is linked to lower obesity risk .

Akkermansia muciniphila

Dysbiosiscan lead to obesity and type 2 diabetesby altering (3) :

– Energy extraction from food. – Insulin sensitivity via inflammatory pathways. – Fat storage by modulating hormones like GLP - 1 and leptin

GLP-1 causes (familiarize)

1. Increased insulin secretion 2. Decreased tissue insulin resistance 3. Increased energy consumption 4. Increased lipolysis 5. Decreased gastric emptying 6. Decreased gastrointestinal motility 7. Decreased lipid content 8. Increased sapiety 9. Decreased appetite 10. Decreased food intake

Leptin causes/helps (familiarize):

1. thyroid hormone synthesis 2. decreased- glucose-stimulated insulin secretion 3. Increased heart rate 4. Regulate bone mass 5. Regulate menstrual cycle 6. Regulate appetite, control metabolism, and energy homeostasis 7. Activation of immune cells 8. Increased blood pressure

_______ connects the microbiome to the nervous system

The gut- brain axis

The gut- brain axis connects the microbiome to the nervous systemvia (3) :

1. Neural signaling 2. Microbial metabolites 3. Immuneregulation

The gut- brain axis: Neural signaling: The ____ transmits gut signals to the brain .

vagus nerve

The gut- brain axis: Microbial metabolites : ____ influence neurotransmitter production .

SCFAs

The gut- brain axis: Immuneregulation: ________ modulate brain inflammation .

Gut bacteria

Certain ________ and ________ strains increase serotonin production, reducing depression and anxiety symptoms .

Lactobacillus; Bifidobacterium

Dysbiosis is linked to ________, ________, and ________(e .g ., Parkinson’s, Alzheimer’s).

1. autism spectrum disorder (ASD) 2. depression 3.Neurodegenerative diseases

______ (Crohn’s disease, ulcerative colitis) is linked to an overgrowth of pro - inflammatory bacteria(e .g ., _______, ________) .

IBD; Escherichia coli, Clostridium difficile

Reduced levels of ______________ are found in IBD patients .

Faecalibacterium prausnitzii

Higher levels of these microbes is linked to obesity

Firmicutes

Higher levels of these microbe is linked to lean individuals.

Bacteroidetes

______________ is associated with colorectal cancer due to its ability to trigger inflammation and suppress immune responses.

Fusobacterium nucleatum

_________ microbial exposure in childhood (due to excessive hygiene and antibiotic overuse) is linked to higher allergy rates (_________)

Reduced; hygiene hypothesis

_________, plant- based dietspromote gut microbial diversity.

High - fiber

Mediterranean diet (rich in fiber, polyphenols) boosts _________ and _________ populations.

Lactobacillus; Bifidobacterium

Western diets (high in ______, _____, and _______) reduce microbial diversity and increase inflammation.

processed foods, sugar, and fat

Opportunistic infections is linked to?

Clostridioides difficile overgrowth

increased obesity risk in children is caused by early exposure to?

early-life antibiotics

______ increases microbial diversity and promotes beneficial SCFA production.

Exercise

______ reduces microbial diversity and can increase inflammatory gut bacteria.

Chronic stress

How do exercise increases microbial diversity? (familiarize)

* Enhancing Gut Motility * Increasing Short- Chain Fatty Acid (SCFA) Production * Reducing Gut Inflammation * Improving Immune Function * Enhancing Oxygenation & Blood Flow * Modulating Stress Response * Influencing Gut- Muscle Axis

How do stress reduced microbial diversity? (familiarize)

* Increased Cortisol & Stress Hormones * Increased Gut Permeability ("Leaky Gut") * Reduced Short- Chain Fatty Acids (SCFAs ) * Imbalance Between Beneficial & Harmful Bacteria * Slower Digestion & Reduced Gut Motility * Changes in Immune Function * Poor Sleep & Dietary Habits Due to Stress

Live Beneficial Microbes

Probiotics

Used to restore microbial balance.

Probiotics

Probiotics common strains (2) :

Lactobacillus rhamnosus & Bifidobacterium longum

______ use can reduce antibiotic - associated diarrhea.

Probiotic

Fiber That Feeds Beneficial Microbes

Prebiotics

Prebiotics are found in (4):

garlic, onions, bananas, and chicory root.

______ a prebiotic fiber, promotes Bifidobacterium growth.

Inulin

Restores gut microbiota by transplanting stool from a healthy donor

Fecal Microbiota Transplantation (FMT)

Highly effective (>90% success) in treating recurrent C. difficile infections.

Fecal Microbiota Transplantation (FMT)

Fecal Microbiota Transplantation (FMT): (Familiarize)

1. Informed Consent & Privacy 2. Equity & Access to Microbiome - Based Treatments 3. Environmental and Ecological Risks 4. Safety & Regulation 5. Commercialization & Biopiracy 6. Dual- Use Concerns (Good vs. Harmful Applications)

Microbial Ecology Flashcards

(90 cards)