Microbiology

Anton Van Leuwenhoek

Anton Van Leuwenhoek

• Refined the Simple microscope

• Discovered many types of cells Called microbes “animalcules” or “beasties”

Simple Microscope

1 lens ( ocular/eye piece)

Compound Microscope

• 2 lens ( ocular/eye piece, objectives)

• Higher magnification power

Robert Hooke

Discovered and named “cells”

Theodore Schwann and Matthias Schleiden

• Proposed the Classical Cell Theory

• All organisms are made up of cells

• Cells are the basic unit of life

• All cells come from cells

Rudolf Virchow

Proposed the Theory of Biogenesis

Theory of Biogenesis

living things arise from living things

Theory of Abiogenesis or Theory of Spontaneous Generation

living things arise from non-living things

GERM THEORY OF DISEASES

• States that microorganisms known as pathogens or "germs" can lead to disease.

• anticipated by Ignaz Semmelweis (1818– 65) and consolidated by Louis Pasteur (1822–95)

Miasma Theory

It held that diseases such as cholera, chlamydia infection, or the Black Death were caused by a miasma, a noxious form of "bad air" emanating from rotting organic matter

LOUIS PASTEUR’S SWAN-NECK FLASK EXPERIMENT

fermentation and the growth of microorganisms in nutrient broths did not proceed by spontaneous generation

Joseph Lister

Father of antiseptic surgery

Phenol

Joseph Lister used _ or carbolic acid as an antiseptic before surgery

Paul Ehrlich

Father of chemotherapy

Salvarsan

first chemotherapeutic agent discovered and scientifically evaluated

Anton Van Leuwenhoek

Father of microbiology

• Mycobacterium Tuberculusis

• Vibrio cholerae

• Bacillus Anthracis

Robert Koch discovered

Edward Jenner

Father of Immunulogy

Cow pox

Vaccinia Virus

Small pox

Variola virus

FALSE

The suspected organism should be present in the DISEASED animal

TRUE OR FALSE

The suspected organism should be present in the HEALTY animal

TRUE

TRUE OR FALSE

The organism must be isolated and grown as pure culture in the lab

TRUE

TRUE OR FALSE

The organism must initiate the symptoms of the disease in healthy animals

TRUE

TRUE OR FALSE

The organism must be re-isolated from the animal and re-cultured again in the lab

Carl Woese, Otto Kandler and Mark Wheelis

Three domain system was introduced by

Archaea

• prokaryotes

• Cell walls have no peptidoglycan

• Live in extreme environments

• Includes: methanogens, extreme halophiles and hyperthermophiles

Bacteria

• Aka Eubacteria or True Bacteria

• Prokaryotes

• Cell walls have peptidoglycan

• Includes: Mycoplasma, Cyanobacteria, Gram-positive and Gram-negative bacteria

Eukarya

• Eukaryotes

• Not all possess a cell wall, but for those with cell walls, the wall has no peptidoglycan

• Subdivided into 4 Kingdoms

• Protista - Algae and Protozoans

• Fungi - Mushrooms, Yeasts and Molds

• Plantae - Plants, Mosses, Conifers, Ferns

• Animalia - Animals, Insects, Worms

4 kingdoms of eukarya

Prokaryotes

Prokaryotes or Eukaryotes

No true nucleus

Prokaryotes

Prokaryotes or Eukaryotes

MEMBRANE-BOUND ORGANELLES: absent

Prokaryotes

Prokaryotes or Eukaryotes

CELL WALL; consists of peptidoglycan

Prokaryotes

Prokaryotes or Eukaryotes

CELL MEMBRANE; present with no sterols

Prokaryotes

Prokaryotes or Eukaryotes

VACUOLE; absent

Prokaryotes

Prokaryotes or Eukaryotes

RIBOSOMES; 30s, 50s

Prokaryotes

Prokaryotes or Eukaryotes

CELL DIVISION; binary fission

Prokaryotes

Prokaryotes or Eukaryotes

• CHROMOSOMES; ; Naked and Circular

• With Plasmids (F Plasmid, R Plasmid, Cosmid)

Eukaryotes

Prokaryotes or Eukaryotes

Has true nucleus

Eukaryotes

Prokaryotes or Eukaryotes

MEMBRANE-BOUND ORGANELLES; present (Lysosomes, Golgi Bodies, Endoplasmic Reticulum, Mitochondria, Chloroplasts)

Eukaryotes

Prokaryotes or Eukaryotes

CELL WALL;

• Fungi - chitin

• Plant - cellulose

Eukaryotes

Prokaryotes or Eukaryotes

• CELL MEMBRANE; present with sterols

  • Cholesterol

  • Phytosterol

  • Stigmasterol

Eukaryotes

Prokaryotes or Eukaryotes

VACUOLE; present (plant)

• Storage organelle

• Maintains the turgidity of the cell

Eukaryotes

Prokaryotes or Eukaryotes

RIBOSOMES; 40s, 60s

Eukaryotes

Prokaryotes or Eukaryotes

CELL DIVISION; mitosis and meiosis

Eukaryotes

Prokaryotes or Eukaryotes

• CHROMOSOMES; Present; Bound to protein

• No Plasmids

Cholesterol

Animal sterols

Phytosterol

Plants sterol

Stigmasterol

Fungi sterol

F plasmid

Plasmid responsible for fertility

R Plasmid

Plasmid responsible for resistance

Cosmid

Plasmid responsible for hybrid/cloning

Sporulation

refers to the formation of spores from vegetative cells during unfavorable environmental conditions (radiation, extreme heat or cold, lack of nutrition). Endospore remains dormant for years

Germination

give rise to a vegetative cell.

Bacillus and Clostridium

• spore formers

• when the condition is unfavorable they protect themselves

Transformation

is a form of genetic recombination in which a DNA fragment from a dead, degraded bacterium enters a competent recipient bacterium and is exchanged for a piece of DNA of the recipient.

Transduction

involves the transfer of a DNA fragment from one bacterium to another by a bacteriophage

Conjugation

is genetic recombination in which there is a transfer of DNA from a live donor bacterium to a live recipient bacterium by cell-to-cell contact. In Gram-negative bacteria it typically involves a conjugation or sex pilus

sex pilus

genes that allow the plasmids DNA to be transferred between cells; The F+ cells have a tube-like structure called a _

Transposons

• “Jumping genes"

• DNA sequences that more from one location on the genome to another

• contains a number of genes, such as those coding for antibiotic resistance or other traits

FLAGELLA

FUNCTION: motility

H antigen

Flagella’s antigen is called

CAPSULE

FUNCTION: evade phagocytosis

• Polysaccharides,

• K antigen

• Bacillus anthracis: Poly D-glutamic acid

Capsule’s composition

K antigen

Capsule’s antigen

monotrichous

has 1 flagella

lophotrichous

has a tuft flagella

peritrichous

has a flagella evenly distributed over the entire surface of the cell

amphitrichous

flagella on both sides

PILI AND FIMBRIAE

• Function: attachment in tissue

• sex pilus: bacterial conjugation

CELL WALL

Function: protection from damage

40 layers

Gram (+) has _ layers

1 layer

Gram (-) has _ layer

TRUE

TRUE OR FALSE

it’s hard to kill gram (-) bacteria because of their outer membrane

Antigen O

Gram (-) cell wall’s antigen

Listeria monocytogens

a gram (+) bacteria that has an endotoxin

TRUE

TRUE OR FALSE

gram (-) bacteria has an endotoxin that is heat stable and toxic to host

Mycoplasma

• Walking pneumonia

• Has no cell wall

Atrichous

No flagella

Endospores

Function: Resistance (Bacillus, Clostridium)

Dipicolinic acid

Composition of Endospores that is heat resistance

121*C 15min 15psi

The minimum sterilizing conditions in a steam autoclave are:

Hans Christian Gram

Developed gram staining

Crystal violet

Primary stain in gram staining

Iodine

Mordant in gram staining

Iodine

intensify the stain

Alcohol

Decolorizer in gram staining

Safranin

Counter stain in gram staining

Deep blue/violet

Gram (+) appears to be __ in gram staining

Pink/Red

Gram (-) appears to be __ in gram staining

• Cocci

• Bacilli

Two main groups of Gram (+)

Cocci

Spherical bacteria

Bacilli

Rod bacteria

• Staphylococcus

• Streptococcus

• Enterococcus

Coccis:

• Spore forming

• Non-spore forming

Bacillis:

• Bacillus

• Clostridium

Spore forming bacillis

• Corynebacterium

• Listeria

Non-Spore forming bacillis

Spirochetes

• Borilla

• Leptospira

• Treptonema

Main group of gram (-)

Spirochetes

Spiral shaped bacteria

Thermophiles

heat-loving organisms that exhibit optimal growth at a temperature above 60ºC

Mesophiles

grow in the moderate temperature range, from about 20oC (or lower) to 45oC.