• 1676
• men's apparel salesman
• first microscope
• discovered "animalcules"

Who performed this experiment with these results?

Flasks with boiled broths are left open to air that had passed though a red-hot glass tube

Concludes air carries germs

Flasks with boiled broths are stoppered with sterilized cotton/wool

Concludes cotton/wool can keep germs out when used as stopper and that air carries germs that are obstructed by the cotton/wool

He took flask of broth with curved necks. Air could flow in, but because the path was so long, bacteria would get caught and/or settle in the curves of the nexk. The broth would stay sterile for a while unless the neck was broken off, then it would turn.

DISPROVED SPONTANEOUE GENERATION

1877 Tynall noted that the conditions amongst those who tryied to recreate P's work were inconsistent. Hypothesized some germs were heat-resistent.

Cohn demonstrated existence of endospores.

Estaliblished the Germ Theory of disease:

Demonstrated the role of bacteria in causing disease

Linked anthrax with Bacillus anthracis

Germ Theory of Disease

Employed  a series of postulates to establish relationships as causative agents of disease

Used mice as models

Tracked infections by symptom

Isolated individual microbes in pure culture

1. microbes must be present in infected part but not health organisms
2. suspected microbe must be able to be isolated and grown in culture
3. same disease must manifest when microbe placed in health organism
4. same microbe must grow from #3

• Produce/Food (cheese, bread)
• recycle nutrients
• fertilize soil
• synthesis of products
• bioremediation

Bacteria grow very fast and in bulk, can beused in to make things like ethanol

Also, GEMS (genetically engineered microbes) can be made to replace by altering the DNA to sythesize chemicals needed by the body i.e. insulin, clotting factors

1. lightfield
2. darkfield
3. phase contrast
4. fluoresent

• light background, images dark
• must have natural pigments or stains (not good for living)
• light passes thru and around specimen to obj

images are _______ background is ______

no need for stain/pigment; ___ for live specimens

Light is ______&_______ by a disc (patch stop) creating an __________________________

The scattered light is collected and passed into the objective lens

1. light
2. dark
3. blocked
4. scattered
5. good
6. outer ring of illumination

Images appear dark; background light

No stain; good for live specimens

Light that passes thru specimen combined with scattered light

dense areas appear dark with glow on edges

1. lightfield
2. phase contrast
3. darkfield
4. fluorescence

1. darkfield
2. fluroscence
3. phase contrast
4. light

Fluorescence

Light is transmitted through the specimen using an excitation filter so only a certain range of wavelengths  (i.e. blue) pass into the specimen

Pigments/dyes emit a different wavelength of light (i.e. green) after excitation – only these wavelengths of light are transmitted to the eye  after passage through a barrier filter

Scanning Vs Transmission

S-the electron beam hit surface of metal coated specimen

T-electron bean penetrates specimen and scatters then

B- electron bounces back to detector to produce image

S-good for intracellular structure

T-good for surface structure

S-~100x better than light

T-~1000x better than light

• preserves the structure in the cells
• inactiviates enzymes that may alter morphology
• prevents cell degradation
• toughen cell walls/other structure

Heat Fixation

• air-dried specimen is passed through a flame
• +good for morphology, not for delicate internal structures
• *if not dried completely, internal structures will boil and lyse

Chemical

• uses formeldyhyde, ethanol, etc
• penetrates the cells to internal structures and toughens them so details can be easily seen
• *many chemicals are toxic to bacteria

Enters vacant cells rendering them pink/red

1. Crystal violet
2. stains everything purple
3. Mordant (fixes primary stain) (chemical)
4. 95% ethanol
5. lipopolysaccharide 
6. Safranin

1. Carbolfuchsin
2. Cooling
3. Slides are cooled
4. Acid alcohol
5. Methylene blue

Turns vegetative cells pink/red

Monotrichous- ___________

_______- two flagella at one pole

__________- a tuft(3+) of flagella at one pole
Amphitrichous- _________

_________- flagella surrounding perimeter *not polar

__________- tufts at both poles

1. one flagellum at one pole
2. Bitrichous
3. Lophotrichous
4. one flagellum at each pole
5. Peritrichous
6. Amphilophotrichous

ARRANGEMENTS OF BACTERIA

Diplo-____________

_________-Chains

Staphylo-________ (coccus only)

Sarcina-__________

1. Pairs
2. strepto
3. clusters
4. cubical packets of 8

Morphologies

____: spherical

Bacillus: straight rods

_____: gently curved rods, comma-shaped

______/_____: helical rods

Pleomorphic _____________

Appendaged: __________

1. Coccus
2. Vibrio
3. Spirilla or Spirochete
4. (shape depends on age or reproductive style)
5. have tubes or stalks

• Intracycoplasmic Membranes
• Inclusions
• Nucleoid & Plasmids

• Microtubules (transport, cell organization)
• Tubulin in Eukarya)
  
  • Microfilaments  (miosis/mitrosis)
  • Actins in Eukarya
  • Intermediate filaments
  • Lamin & keratin in Eukarya

1. conjugative- horizontal gene transfer
2. virulence- carry virulence genes (dieseae causing)
3. metabolic
4. col-colicin production (antibiotics)

Granules/gas vaculoes

may have phosphlipid bilayers

storage purposes

• PHB-only in purple photosynthetic bacteria; lipid/carbon E source
• Glycogen-starch/found in many bacteria
• Volutin-polyphosphate resevoirsfound in many bacteria
•  sulfur globules-purpple photo
• cyanophycin-aa synthesis and N source in DNA/cyanobacteria
• carboxysomes-rubisco; protein coat
• magnetosomes
• gas vacuolues-buoyancy

Number of Ribosomes in Archae/Euks?

In pros?

50s+30s=80s

40s+60s=100s

Endospores contaon _____________ which was thought to cause heat-resisitstance

____________ is thought to stabilize DNA

dipicolinic acid

calcium dipicolinate

activiation (heat)

germination (swells and ruptures)

outgrowth (new components--> vegative growth)

• lipopolysaccrides (LPS) outer most component
• Braun’s lipoproteins anchor outer membrane to peptidoglycan layer
• larger periplasmic space
• thin peptoglycan
• contains porins

exopolysaccarides (EPS)

make up slime layers and capsules

energy/protection

S-loose&solube

C-tight and closely bound

S-protects again drying out

C-prevents against dessication

S-invovled in biofilm formation

C-aids in attachement to surfaces

C-mosly polysaccrides, can be proteins

Slime layers (S-layers) are most commonly found in Archae and Gram (-) bacteria.

true or false

False

Most common in archae; sometimes in gram (-) and (+)

In gram (-)'s; s-layer bounds to ____________

In gram (+)'s, s-layer associated with _________

in arcae, s-layers _________

outermembrane

peptoglycan

may be the the only cell wall component present

s-layers are regulary structures layer of ___________ patterned like floor tiles;

protects against __________; osmotic pressue; and _________

protien/glycoprotein;

pH fluctuations

hydrolytic enzymes and predatory bacteria

characteristics are displayed by Gram-negative bacteria:

1. Cytoplasmic membrane
2. Thin peptidoglycan layer (which is much thinner than in Gram-positive bacteria)
3. Outer membrane containing lipopolysaccharide (LPS, which consists of lipid A, core polysaccharide, and O antigen) outside the peptidoglycan layer
4. Porins exist in the outer membrane, which act like pores for particular molecules
5. There is a space between the layers of peptidoglycan and the secondary cell membrane called the periplasmic space
6. The S-layer is directly attached to the outer membrane, rather than the peptidoglycan
7. If present, flagella have four supporting rings instead of two
8. No teichoic acids or lipoteichoic acids are present
9. Lipoproteins are attached to the polysaccharide backbone.
10. Most of them contain Braun's lipoprotein, which serves as a link between the outer membrane and the peptidoglycan chain by a covalent bound
11. Most do not sporulate (Coxiella burnetii, which produces spore-like structures, is a notable exception

1. cytoplasmic lipid membrane
2. thick peptidoglycanlayer
   • teichoic acids and lipoids are present, forming lipoteichoic acids, which serve to act as chelating agents, and also for certain types of adherence.
3. capsule polysaccharides (only in some species)
4. flagellum(only in some species)
   • if present, it contains two rings for support as opposed to four in Gram-negative bacteria because Gram-positive bacteria have only one membrane layer.
5. The individual peptidoglycan molecules are cross-linked by pentaglycine chains by a DD-transpeptidase enzyme. In gram-negative bacteria, the transpeptidase creates a covalent bond directly between peptidoglycan molecules, with no intervening bridge.

If forgot to decolorize: gram(+) and gram (-) would ______

If forgot to do counter stain-gram (_______) would be clear gram (_________) would be purple

be purple

(-)/(+)

Bacterial Flagella Structure:

Filament

• ___________
• Growth at ____ end (begins in the ________)
• subnits move down hollow core; assemble spontaneously

hollow, rigid, helical, cylindar

distal (away from cell); cytoplasm

Bacterial Flagella Structure:

Hook

is achored to the ________

Bacterial Flagella Structure:

Basal Body

• _____ for rotation; ____ like a ______
• embedded in ___________
• has direct path to the __________

motor;spins/propellor

cell wall

cytoplasm

fimbrae only for attachement

pilli-bacterial conjugation; movement of stuff

With O₂ normal: chemoautotrophy

with O₂ absents: _{photoorganotropy}

with O2 low: combo (E from light and organic chemicals)( carbon/e from organic molecules)

*some photolitroautotrophs (H=e-donor

1°-ATP--> ADP + Pi (ATP binding cassette transporters ABC)

2°-potenail E from gradients created through passive transport

periplasmamic space;

tethtered as lipoproteins on external phospholipid bilayer

anitports-Proton-motive force drives expulsion of Na+ from the cell as H+ enters

/symports-

Conformational change in carrier occurs to release Na+ and solute inside the cytoplasm