Kingdom Monera

• All prokaryotic• Unicellular• Metabolically the most diverse

– Photosynthetic autotrophs– Chemosynthetic autotrophs– Chemosynthetic heterotrophs– Photosynthetic heterotrophs– Obligate anerobes– Facultative anaerobes

• Members include bacteria and blue-green bacteria• Extremophiles

Ecological/Economic Importance

• Ecologically, monerans are major decomposers in the world’s ecosystems

• Many have symbiotic relationships: some mutualistic, some parasitic

• Economically they can be used in food production, in the manufacture of artificial snow, in mining, and in biotechnology in the manufacture of pharmaceuticals

Basic Anatomy of the Prokaryote

Look Mom! No organelles!!!!! (except for ribosomes…why???)

Some bacteria have plasmids

Plasmids are used in biotechnology to carry foreign genes into bacterial cells

The cell walls of prokaryotoes

• contain a unique substance called peptidoglycan

• This substance is found only among prokaryotes

• The thickness of the peptidoglycan layer helps to differentiate between types of bacteria

Bacterial Shapes

• Bacteria can be classified according to three main shapes:– Round bacteria (cocci)– Rod shaped bacteria (bacilli)– Spiral shaped (spirilla)…

Anthrax

The Gram Stain

• Used to help distinguish types of bacteria

• Gram positive (appear purple when stained)

• Gram negative (appear pink when stained)

• Those bacteria with thick peptidoglycan layers will stain purple (Gram +) because the thick layer retains much of the stain

Anthrax

Comparison of Gram positive and Gram negative bacteria

“Scalded Skin Syndrome”(a type of “staph” infection)

Avert your eyes if you are squeamish!!!!!

Reproduction bybinary fission

But can do some other cool genetic rearrangements…

transduction

Bacterial conjugation

transformation

Bacterial Endospore

Controlling bacterial growth

• Sterilization by using an autoclave (or pressure cooker)-the only way to kill all bacteria

• Antibiotics

• Temperature (freezing will stop bacterial growth but not kill the bacteria; refrigeration will only slow down the growth

Microbes: The unseen majority on Earth

Did you know that microbes : - By weight, represent 60% of the biomass of all life on Earth- Are found everywhere on Earth, but are largely unculturable- Constitute more cells in the human body than human cells

- Are the oldest form of life on Earth (~ 3.8 billion years)- Produce more than 1/2 of all the oxygen we breathe- Can cause disease, but the vast majority do not...

The Domain Bacteria and Domain Archea

• Peptidoglycan wall

• One kind of RNA• Introns rare• No histones on DNA• Circular chromosome

• Absent• Many kinds of RNA• Present in some• Histones• Circular chromosome