Oral Microbiology test 1

Edward Jenner 1790s

immunization, he injected a boy with fluid from a cowpox than it caused smallpox

Hans Christian J. Gram 1884

gram staining

Eukaryote examples

Fungi, protista (algae and protozoa), plantae, animalia

cellular examples

bacteria, archaea, fungi, protozoa

Gives cell its shape, non-living, simple:

cell wall

Microaerophiles

4% oxygen for growth (need SOME oxygen)

Endogenous

· Source within the host
· Primary source of nutrients for oral microbiota

Pioneer colonizers in a human after birth are?

streptococci spp.

Pioneer Communities in Babies are?

only on mucosal surface

Predominant species of the: Tongue

•Streptococci (salivarius, oralis, and mitis) • Actinomyces •Veillonella

Subgingival calculus is?

much harder and forms more slowly

Babies born through cesarean will often have which predominant microbial community?

Staphylococcus spp.

Babies that are nursed will have which microbes present?

Lactobacilli

These microbes are common on skin surfaces and in the nose?

Staphylococcus

Which microbe is associated with gingivitis?

A. naeslundii

Thrush which commonly affects the tongue in infants is linked to which type of organism?

fungi

What are the main characteristics of normal human microbiota?

work in symbiosis (together) with host directly or indirectly

What are the benefits to a human body of microorganisms?

-Medicine/Health
-Food/Chemicals
-Biodegradation
-Biofertilization

What will occur when a host resistance is decreased?

microorganism that will take the "opportunity" to invade (opportunistic pathogen)

Antoni van Leeuwenhoek 1667

observed "animalcules" (bacteria, yeasts, protozoa) under a simple microscope

Louis Pasteur 1855/1861

father of immunology, pasteurization, germ theory

Joseph Lister 1865

carbolic acid/phenol would work as an antiseptic to decrease chance of dying after surgery due to infection

Robert Koch 1876

Proved that microbes cause disease by proving that bacteria caused anthrax and TB

Friedrich Loeffler and Gerolamo Fracastoro 1898

discovered that something smaller than bacteria could cause foot and mouth disease

Alexander Fleming 1929

discovered penicillin

Eukaryotes' Key Features

-reproduce by meiosis or mitosis
-have a nucleus and nucleolus
-multicellular
-larger
-membrane bound organelles
-more complex structures

Prokaryotes key features

-reproduce asexually by binary fission
-no nucleus
-no membrane bound organelles
-smaller
-capsules/slime layer
-spores
-simple structure

Prokaryote examples

Bacteria, Cyanobacteria, Archaebacteria, Eubacteria

Virus structure

Contains genetic material either DNA or RNA, and a protein coat.

characteristics of a virus

· Contains DNA or RNA than surrounded by a capsid
· Cannot replicate on their own, NEEDS A HOST
· DO NOT divide by binary fission, mitosis, or meiosis
· Lack genes and enzymes necessary for energy production
· Depends on a host cell for ribosomes, metabolites, enzymes, protein, and nucleic acid production
· Smaller than bacteria
· Some viruses have an envelope

Life cycle of a virus

Adsorption, penetration, uncoating, replication, assembly, release

Acellular

Has no cells (not living)

acellular examples

viruses, viroids, prions

Cellular

Has cells (living)

cocci

round/spherical

bacilli

rod

Spirilla

curved/spiral

This organelle contains the majority of genes and DNA:

nucleoid

This organelle will commonly be altered by disinfectant agents, complex, semi-permeable, living:

cell membrane

This organelle aids in movement:

flagella

Jelly like, viscous material:

cytoplasm

Slime layer, protect the cell from body defense mechanisms:

capsule

Short, hairlike appendages:

fimbriae/ pilli

Defense mechanism caused by bad environmental conditions, resistant to o heat, drying, and chemicals, remain dormant for years:

endospores

How sterilizers are monitored?

Geobacillus stearothermophilus and Bacillus atrophaeus spores

Thermophiles

45-70 degrees, HOT

Mesophiles

22-45 degrees, human body temperature

Psychrophiles

1-22 degrees, COLD

Acidogenic

produces acid

Aciduric

survive and thrive in acidic environment

Obligate aerobes

20% oxygen for growth (NEED oxygen)

obligate anaerobes

NO oxygen

Facultative anaerobes

can live with/without oxygen

What is redox potential?

Anaerobic species require reduced conditions for their normal metabolism; therefore, it is the degree of oxidation reduction (redox potential)

Main source of endogenous nutrients in the mouth?

saliva

exogenous

· Ingested by the host

vertical transmission

mother to child (different generation)

horizontal transmission

adult to adult (same generation)

Pioneer colonizers

First microorganism colonizers

Physical examples of pioneer colonizers

Desquamation, chewing, saliva flow

Chemical examples of pioneer colonizers

Redox potential, pH, antibacterial properties of saliva

direct effects of aging (can't be avoided)

• Immunity decreases
• Antibody response decreases found in saliva
• Hormonal change

indirect effects of aging (can be avoided but common in old people)

• Dentures
• Medication
• Cancer treatment
• Diet changes

Predominant species of the: lips

•Staphylococci
•Corynebacterium (gram positive rods)
•Streptococci (facultatively anaerobic cocci)

Predominant species of the: Cheek (mucosa)

•Streptococci (salivarius, oralis, and mitis)

Predominant species of the: Palate

•Streptococci • Actinomyces

Predominant species of the: Teeth/ Dentures

•Streptococcus • Actinomyces • Prevotella • Fusobacterium •Treponema • Unculturable organisms

Halitosis link to microbes

· Resulting from metabolism of microorganisms on the tongue

supragingival calculus

gram-positive
aerobic

subgingival calculus

gram-negative
anaerobic

What is tropism?

the ability of a microbe to move in response to a stimuli

Stages of biofilm formation

1.Acquired Pellicle formation
2.Intial adhesion
3.Coaggersion
4.Maturation
5.Detachment

Sites that have active disease such as periodontitis will have a temperature of?

39 degrees C

GCF

provides nourishment to microbes and host protection

Aggregatibactor actinomycetmcomitans or A.a. is a gram NEGATIVE organisms with which shape?

Bacilli

Herpes found in the oral cavity and surrounding the oral cavity is most often?

HSV 1

what % of human microbiota is good/bad?

good: 90%
bad: 10%

What is dysbiosis?

An imbalance of human microbe

3 factors that need to be present for dysbiosis to occur?

host, environment, microorganism

Niche

The way a microorganism USES its environment

opportunistic pathogens

-microbes that can cause disease
-thought of as microbes that are awaiting the opportunity to cause disease

Resident Microbiota

Lifelong microbial occupant of a particular area (a resident of that specific area)

Girolamo Fracastoro (1546)

"catching" disease