Bacteriology and Oral Diseases; pptx 1 & 2(PRE QUIZLET)

bacteriology

study of bacteria and archaea

Mycology

study of fungi

Parisitology

study of parasites

virology

study of viruses and prions

what are prions?

misfolded versions/mutated protein that can cause disease

what is the size of Bacteria & Archaea

0.5 - 5µm

conversion from micrometer(µm) to millimeter(mm)

1µm = 0.001mm

what is the size of Protozoa?

5-1,000 µm

What is the size of fungi?

5-100µm

what is the size of viruses?

0.002 - 0.05µm

how did bacteria allow the production of other living organisms?

-used photosynthesis

-produced oxygen

-recycling of elemental nutrients

-allow for nitrogen fixation

-break down organic matter(shit)

how do bacteria help animals?

-prevent potential pathogens form gaining a foothold

-help digest good

-provide essential nutrients

- can break down cellulos

what essential nutrients do bacteria help provide?

vitamin K and B

what is passing gas the biproduct of?

bacteria breaking down food in an organisms stomach

bovine rumen

organ that harbours bacteria that digest cellulose and other polysaccharides

bacteria allow cow to obtain nutrients from grass/grain diets. Cow provides habitat for bacterial growth and a continual food supply

Beneficial cultural impact of microbes

-production of biofuels

-production of fermented foods

-production of antibiotics and drugs

-sewage treatment

Detrimental cultural impact of microbes

-Industrial biofouling

-food spoilage

-Disease

Robert Hooke

-reported that living things were composed of little boxes or cells

-The first to describe microorganisms

Antoni van Leeuwenhoek (1632-1723)

first to describe bacteria, further progress required development of more powerful microscopes

Discoveries by Leeuwenhoek

-Bacteria

-Yeast

-Protozoa

-Blood Cells

-Capillaries

-blood circulation

-spermatozoa

-muscle fibers

-dust mites

-nematodes

-rotifers

Louis Pasteur's experiments

-Disproved spontaneous generation. Said that all cells come from preexisting cells (Cell Theory)

-microbes cause fermentation

-Pasteurization

Studies on fermentation

-Alcoholic fermentation is caused by living yeast cells

-Fermentation does not require oxygen

-Wine is spoiled by lactic acid-producing bacteria

Pasteurization prevents the spoilage of wine

Spontaneous generation

the mistaken idea that living things can arise from nonliving sources, disproven by Pasteur through his experiment with 1 sterile and one non sterile broth

Robert Koch

-Development of pure culture methods

-Microbes cause disease

-streak plate

Who suggested the use of agar instead of gelatin for streaking?

Dr. Hess's wife

Why is agar a better solidifying agent than gelatin?

it has a higher melting point

what is agar made from?

seaweed

Koch's Postulates

a sequence of experimental steps for directly relating a specific microbe to a specific disease

What are Koch's postulates?

1. The same pathogen must be present in every case of the disease.

2. The pathogen must be isolated from the diseased host and grown in pure culture.

3. The pathogen from the pure culture must cause the disease when it is inoculated into a healthy, susceptible laboratory animal.

4. The pathogen must be isolated from the inoculated animal and must be shown to be the original organism.

Alexander Fleming

discovered penicillin

Age of molecular biology

1944-1966 and included:

-DNA

-mRNA

-Ribosome

-tRNA

-Codon

-Genetic code

-Gene

-Operon

Age of genetic engineering

1973-1977 and included:

-Restriction endonuclease

-Recombinant RNA

-DNA sequencing

Age of genome sequencing

1995-present and includes:

-First bacterial genome sequence

-First metagenomic sequence

-Bacterial genomes sequenced

660,00 bacterial genomes sequenced

Willoughby B. Miller

-chemo-parasite theory of caries

-Focal infection theory

-Bacteria produce acid in oral cavity that causes tooth decay

focal infection theory

A hypothesis that bacteria existing in a primary site-the focus-may gain entry into the circulatory system and cause diseases elsewhere in the body.

What kinds of bacteria usually have a pigment? why?

Bacteria that grow in the air because it protects them from light (UV radiation)

If a bacteria reflects light

that usually means that they have a capsule

Polymorphic bacteria

Bacteria which change their structure depending on environment and gene expression

coccus

round

Rod (bacteria)

bacillus, rod shaped

Spirillum

spiral shaped bacteria

spirochete

A bacterium having a spiral shape (plural = spirochetes)

appendaged bacteria

possess extensions of their cells as long tubes or stalks

filamentous bacteria

form long, thin cells or chains of cells

Scientific names for organisms

genus and species

what are the rules when writing the names of organisms?

The names are italicized of underlined. The genus is capitalized and the species if lower case. After first use, can be abbreviated with the first letter of genus and the species e.g. Escherichia coli --> E. Coli

Pathogenesis

ability for disease to develop

transmission electron microscope (TEM)

An electron microscope used to study the internal structure of thin sections of cells

pepdidoglycan

the polymer made of sugars and amino acids found in the cell wall of bacteria.

What is the composition of the cell membrane of bacteria?

Composed of phospholipids similar to that of eukaryotes

What are the functions of the cell membrane in bacteria?

-permeability; prevent leakage and functions as a gateway for transport of nutrients into and out of the cell

-protein anchor; site of many proteins involved in transport, bioenergetics, and chemotaxis

-energy conservation; site of generation and use of the proton motive force(the gradient)

Would a antibiotic that is designed to attack the cell membrane on a bacteria also attack our(human) cells?

Yes, it can damage our cells as well since they are composed of the same structure

can antibiotics bypass the cell membrane easily?

No

gram-negative

Describing the group of bacteria that have a cell wall that is structurally more complex and contains less peptidoglycan. Often more toxic than gram-positive bacteria.

gram positive

Describing the group of bacteria that have a cell wall that is structurally less complex and contains more peptidoglycan. Usually less toxic than gram-negative bacteria.

LPS (lipopolysaccharide)

A molecule consisting of lipids and polysaccharide moieties that is a major component of the cell wall of gram negative bacteria.

Which bacteria type is it harder to produce antibiotics for? why?

gram-negative, because it has 2 cell membranes

peptidoglycan structure

Chains of sugars (NAG and NAM) which are connected by a β 1-4 cross link which also has a peptide interbridge link between 2 NAMs from with the other chains on either side connecting them together to make a mesh like structure

peptidoglycan transpeptidase