Microbe Mission Sci Oly

Prions

Abnormal, transmissible pathogenic protein that induces abnormal folding of normal proteins in the brain.

Approximate size of viruses

10-100 nanometers -- smaller than bacteria

Bacteria

single-celled prokaryotic organism -- no nucleus

How do motile (capable of motion) bacteria move?

rotating flagella or slime secrections

This RNA molecule often possesses a highly compact, intricate secondary structure.

Viroids

Explain phase contrast microscopy

uses transmitted illumination to observe colorless and transparent and unstained specimens such as living cells.

No staining required

Simplest optical microscopy technique

Bright field

Explain bright field microscopy

Used to view fixed specimens or live cells. Since many organic specimens are transparent or opaque, staining is required to cause the contrast that allows them to be visible under the microscope.

Microscope that is reserved for research organizations

Confocal microscope

Which microbe originates from the single-celled organisms that were the first to inhabit the Earth.

Bacteria

Most advanced microscope

Electron microscope

Which microscope is used to help assemble a data into a 3D image?

Confocal microscope

Which microscope is used for cell suspensions, red cell agglutinates, cell cultures, tissue culture

Reflected/inverted light microscopes

Archaea is a type of bacteria (true/false)

False

Do archaea form spores?

No

Which microorganism shares a common ancestor with eukaryotes?

Archaea

Are archaea pathogenic?

No

Define archaea

Single-celled, prokaryotic microorganisms. Many are extremophiles.

Fungi

a group of heterotrophic eukaryotes that can be single-celled or multi-celled.

Which organism produces half the oxygen in the atmosphere and stores CO2?

Algae

Why is algae economically important? (3 reasons)

1. crude oil

2. food source

3. used in pharmaceutical and industrial products

What structures do algae lack?

roots, stems, leaves, and specialized multicellular reproductive structures

Function of nuclei

The control center of eukaryotic cells, responsible for coordination of genes/gene expression.

Structure of nuclei

Nuclear membrane, chromosomes, nucleoplasm, and nucleolus.

Mitochondria function

Generate most chemical energy (ATP) needed to power biochemical reactions.

What microorganism was chloroplast derived from?

cyanobacteria

Who championed the theory of symbiogenesis?

Margulis (1960s)

Basic description of symbiogenesis

describes how eukaryotes emerged from interactions between prokaryotic cells.

What bacteria did mitochondria descend from?

alphaproteobacteria

What color do gram negative bacteria stain?

pink/red

Why are gram negative bacteria more resistant to antibodies?

they have an impenetrable cell wall

What color do gram positive bacteria stain? Why?

Stains purple/blue due to thicker walls of peptidoglycan

Acid fast bacteria

Retain the primary stain even when treated with acid alcohol. Cell walls contain mycolic acid. Includes Mycobacterium and Nocardia species which include human pathogens as M. tuberculosis and M. Leprae.

What are viruses that infect bacteria known as?

bacteriophages

Bacteriophage genome is composed of ______ (DNA/RNA) as opposed to ______ (DNA/RNA)

DNA; RNA

The theory of symbiogenesis states:

mitochondria, chloroplasts, other types of plastids, and other organelles in eukaryotic cells originated from prokaryotic cells.

Gram staining is not effective on what type of bacteria?

Acid fast bacteria

Agar is a polysaccharide that is derived from ___________

Red seaweed (Rhodophyceae)

Great Plate Count Anomaly

-if you take bacteria from an environment and culture them, you count way fewer species cultured than if you looked at the environment under a microscope

-not all bacteria can be cultured; many species have been missed

Gram positive bacteria are susceptible to _____ disinfectants

phenol

How long does liquid culturing take?

3-6 weeks

Antibiotic resistance

Resistance evolving rapidly in many species of prokaryotes due to overuse of antibiotics. Thus, the bacteria are not killed and continue to grow.

Batch/closed culture

growing bacteria inside a closed container using a fixed volume of medium (without adding new chemicals throughout the growth process).

Chemostat growth (open or continuous culture)

Nutrients are continually added or removed from the medium to achieve constant environmental conditions.

Selective media

selects for the growth of a desired organism, stopping the growth of or killing non-desired organisms.

Differential media

allows growth of several types of microbes and displays visible differences among those microbes; makes it easy to distinguish colonies of different microbes

1. Agar is preferred for _____________ culture media

2. Why?

1. bacteriological

2. it is an inert, non-nutritive substance.

Define complex media

Complex media contains ingredients that have a slightly different chemical composition each time they're used.

When is complex media used?

When the nutritional requirements of the cells are unknown, or when the goal is to obtain a large quantity of cells.

Antibiotic resistance transfer

Antibiotic resistance spreads among bacteria mainly through the horizontal transfer of antibiotic resistance genes

Why do bacteriostatic antibiotics require a fully functioning host immune system?

They only inhibit further bacteria growth.

Define metagenomics

Study of structure/function of nucleotide sequences isolated and analyzed from all organisms (typically microbes) in a bulk sample.

What is metagenomics often used for?

To study specific community of microorganisms, such as those residing on human skin, in the soil or in a water sample.

How do bactericidal antibodies kill bacteria?

by inhibiting cell wall synthesis.

Iron oxidizing bacteria

Chemotrophic bacteria that derive energy by oxidizing dissolved iron.

Green sulphur bacteria

Anoxygenic

• Metabolic specialists - can't tolerate oxygen at all

• No calvin cycle

• Use lowest light intensity of known species - niche that can't be used by other photosynthetic cells

• E.g. Chlorobium

Transduction

process by which foreign DNA is introduced into a cell by a virus or viral vector.

Transformation

process in which one strain of bacteria is changed by a gene or genes from another strain of bacteria

Organism involved in fermentation of bread

Yeast -- Saccharomyces cerevisiae

Microbial competition

Populations of microorganisms in a common area compete for nutrients and other resources. Beneficial when commensal bacteria prevent pathogens from colonizing

Microbe name and usage in algal biofuels

Yeasts and molds, Algae, Escherichia coli, and archaea such as methanogens are extensively employed in production of biofuels

Algal blooms

rapid growth of algae encouraged by too many nutrients (nitrates/phosphates) in the water

Thrush

Yeast infection, grows in mouth, throat and other parts of the body.

Oral thrush is known as

oral candidiasis

What does oral thrush cause

white, raised, cottage cheese-like lesions on tongue and cheeks develop. Becomes irritated, causes mouth pain+redness

Cysts

Small, sac-like pocket of membranous tissue filled with fluid, air, pus, or other substances. Usually benign.

Thermophiles

prefer very high temperature environments.

Halophiles

Prefer environments with high salt concentrations, such as salt lakes.

Enterocolitis

inflammation of the small and large intestines

What does SARS-CoV-2 Virus cause

covid

Influenza A Virus

Causes the flu in birds and some mammals, including humans. It is an RNA virus whose subtypes have been isolated from wild birds.

Influenza A Transmission

spreads mainly by droplets made when people with flu cough, sneeze, or talk.

T4 phage infects which bacterium

Escherichia coli

Canine parvovirus 2 affects which organisms?

dogs and wolves

What organisms does Mimivirus infect?

marine heterotrophic protists, amoebas, plankton populations.

Mimivirus size (nonspecific)

large

What transmits banana bunchy top virus?

aphids

What does vibrio cholerae cause?

Cholera

What type of organism is vibrio cholerae?

bacteria

How is Vibrio cholerae transmitted?

ingestion of fecal-contaminated food or water

Rickettsia rickettsii causes what?

Rocky Mountain Spotted Fever

How is Rickettsia rickettsii transmitted?

tick bite

Bacteriostatic antibiotics

Medications that stalls bacterial cellular activity without directly causing bacterial death.

Streptococcus pneumoniae transmission

direct contact with respiratory droplets

Corynebacterium diphtheriae transmission

usually through respiratory droplets, like from coughing or sneezing.

What disease does Corynebacterium diphtheriae cause?

diphtheria

methicillin resistant staphylococcus aureus causes

staph infection

What 2 diseases does mycobacterium tuberculosis cause?

pulmonary TB and extrapulmonary TB

Cutibacterium acnes

Slow growing, gram positive bacteria

Haemophilus influenzae transmission

People spread H. influenzae, including Hib, to others through respiratory droplets. People who are infected spread the bacteria by coughing or sneezing, which creates small respiratory droplets that contain the bacteria. Other people can get sick if they breathe in those droplets