Do Now Classify the following organisms as as chemoautotrophs, chemoheterotrophs, photoautotrophs, or photoheterotrophs: Clostridium bacteria break down cellulose for carbon and energy Desulfovibrio breaks down organic acids for energy and carbon. Chlorobium does photosynthesis for energy and carbon, but uses H2S instad of H2O Chromatin does photosynthesis for energy and carbon without producing oxygen.

Observations Make your week 2 observations of your Winogradsky columns. Be sure to measure!!! Don’t lose your records – we still have 4 weeks to go. You have 10 minutes maximum.

Introduction to Bacteria There are a RIDICULOUS number of different types of bacteria

They Do Anything Trying to describe the diversity of bacteria is like trying to describe the diversity of eukaryotes: you and an Euglena live very different lives!

One Way is with Oxygen Use – Anaerobic or Aerobic? Anaerobic organisms do not use oxygen. Aerobic organisms require oxygen Facultative anaerobes will use oxygen if it is available Microaerophilic organisms need a little oxygen OXYGEN IS TOXIC!!!

Bacteria = Diversity Bacteria live just about everywhere. Some are chemotrophs, others are autotrophs, and there’s heterotrophs and phototrophs… So where do we begin???

Anaerobes Anerobic organisms are good for lots of things: Beer, wine, saurkraut, yogurt, cheese, vinegar, olives, bread…

Anaerobic Products

Bad Anaerobes: Gas gangrene is an example of a disease caused by an anaerobic bacterial infection. WARNING !!! The next slide is really graphic. It shows gas gangrene. View at your own discretion.

Last chance Don’t say I didn’t warn you. Twice.

Gas Gangrene: Clostridium perfringiens This leg will have to be amputated

Happy Anerobes: In our columns We will now watch part of an animated description of some of the bacteria in a Winogradsky column. For now, we’ll just be talking about the anerobic bacteria at the bottom of the columns.

Clostridium: Anaerobic chemoheterotroph Strict anaerobe – dies in contact with oxygen Breaks down cellulose and then glucose for carbon and energy. Can cause gangrene from untreated deep puncture wounds Can cause food poisioning in canned foods (expanded can)

Desulfovibrio: Anaerobic chemoheterotroph Uses fermentation waste products and sulfate to get carbon and energy Notice: Aerobic organisms produce H2O during respiration. Anaerobes produce H2S

Oxygen: Sulfur lite

Photosynthesis – New Twists OXYGENIC PHOTOSYNTHESIS (plants) H2O + CO2  CH2O + O2 e- donor + inorganic CO2  carbohydrates + e- acceptor ANOXYGENIC PHOTOSYNTHESIS (bacteria) H2S + CO2  CH2O + S2

Anaerobic Photoautotrophs that use H2S during photosynthesis The green and purple sulfur bacteria are seperated by their tolerance of hydrogen sulfide

Not Chlorophyll

Anaerobic Photoautotrophs that use organic molecules instead of H2S Still anaerobic Use waste of other organisms for electrons

The Bottom Line Define: aerobic, anaerobic, facultative anaerobe, microaerophilic. Classify bacteria based on their oxygen requirements. Describe the chemical formula for anoxygenic photosynthesis as done by the green and purple sulfur bacteria.