Bacteria!

Kingdom MoneraProkaryotes

Domain ArchaebacteriaDomain Eubacteria

Generally…

• Different classificationsDifferent classifications

• Very smallVery small

• Reproduce asexually – fissionReproduce asexually – fission

• Unicellular (may live in colonies)Unicellular (may live in colonies)

• Very diverseVery diverse

• Prokaryotes (no cell compartments)Prokaryotes (no cell compartments)

• Around for 3.5 billion years!Around for 3.5 billion years!

http://commons.wikimedia.org/wiki/File:Cholera_bacteria_SEM.jpg

www.darwin.nmsu.edu

What’s the difference??

  Prokaryotes Eukaryotes

cell size ~ 1 micrometer ~ 10 micrometers (varies!)

organelle membrane lacking membranes has internal 'compartments'

multicellular? singular; may form clumps / filaments usually multicellular

genetic material usually single circular DNA(some RNA)

linear DNA that form chromosomes

cell division binary fission;two duplicate daughter cells mitosis with nuclear division

flagella simple; spins;single fiber of protein

more complex microtubules;moves back and forth

metabolic diversity many types anaerobic & aerobic only aerobic

Relative size of cells and other particles…

This website has great information, including this demonstration of relative size

www.answers.com/topic/archaeon

General anatomy of a bacterium

From textbook

Reproduction• Predominantly binary fission

• Many able to reproduce every 20 minutes (!)

• May form endospores

• Genetic recombination may occur– Transformation:

absorb ‘loose’ DNA– Conjugation:

pieces of DNA swapped– Transduction:

involves bacteriophagesFrom textbook

From textbook

Coccus – sphere

Baccillus – oblong

Spirochete - coiled

Common shapes and classification

May also be classifiedby cell structures,

various appendages,movement,

energy source

Wikieducator.net/biology

Gram negative or positive

Gram Positive: retain a violet dye Gram Negative: retain pink dye

Some antibiotics work only on gram-positive or –negative bacteria

From textbook

Archaebacteria (Archaea)

• Ancient bacteria• Developed during early Earth

– 3.5 billion years ago– Adapted to survive in ‘extremes’

• Halophiles• Thermoacidophiles• Methanogens

• May be photosynthetic, autotrophs, heterotrophs, chemosynthetic

Eubacteria (Bacteria)

• Includes some chemoautotrophs, photoautotrophs, heterotrophs

• Cyanobacteria

• Different from Archaea:– In DNA & RNA– In polymerase (simpler in Eubacteria)– Peptidoglycan present in Eubacteria cell wall

(not Archaea or Eukaryote cell walls)

Not-so-beneficial BacteriaMay impact in a variety of ways

• Clostridium botulinium – produces toxic protein; food poisoning

• Staphylococcus aureus – produces toxic protein; common on skin, harmful inside body

• Salmonella spp. – food poisoning & typhoid fever

CholeraSyphilisAnthraxLeprosyBubonic Plague

TuberculosisRocky Mountain Spotted FeverTetanusDiptheria

From Wikipedia

Beneficial Bacteria• Oxygen producers• Decomposers• Bioremediation• Production of food

– Lactobacillus, Lactococcus• Pest control

– Bacillus thuringiensis• Digestion • Production of methane• Study of biology• Production of medicines• Nitrogen-fixing bacteria• Flashlight fish • Symbiosis with fungus

Bacteria&

You…