Test 1- Chromatium vinosum Flashcards
What is its cell wall like?
Gram -
What is its organization in terms of flagella?
Polar monotrichous.
What is its unique feature involving the periplasm? Where is the periplasm?
Periplasm is between CW and PM. Intracellular Sulfer Granules stores Sulfur.
What is its unique feature involving the PM? What is it?
Chromatophore, which is a membrane enclosed structure with photosynthetic proteins.
What group does it belong to?
Purple Sulfur Bacteria
Is it an aerobe or an anaerobe? What metabolism does it perform?
Strict anaerobe, so no oxidative phosphrylation.
It is a (chemo/photo)(autotroph/heterotroph)
Photoautotroph.
What is different about Chromatium vinosum’s photosynthesis?
No O2.
What are 2 steps of anoxic photosynthesis?
- Light Capturing
2. Converting CO2 into Carbohydrate (with E. from Light)
Why can’t CO2 be used as an energy source itself? Where does the reducing power come from?
CO2 is oxidized. Reducing power comes from NADPH (from H2S) and ATP, which will be oxidized as CO2 is reduced.
Anoxic Photosynthesis: What 2 proteins capture light?
- Bacteriochlorophylls
2. Carotnoid.
Anoxic Photosynthesis: What structural components allow chlorophyll to absorb certain wavelength of light? Be specific. Chlorophyll a or b?
- Ring structure allows e- to be raised into + E state.
- Group attached to chlorophyll determines which wavelength is absorbed. (CH3 in chlorophyll a or CHO in chlorophyll b?)
Anoxic Photosynthesis: Where are the chlorophylls located?
Within the chromatophores.
Anoxic Photosynthesis: What do chromatophores look like? Which 3 components are there? Show flow of E.
- Outermost is Light Harvesting II (LHII), which absorbs light and passes E to LHI.
- Middle is Light Harvesting I (LHI), which absorbs light from LH II and passes E to RC.
- Innermost is Reaction Center (RC), which is where photosynthesis occurs.
Anoxic Photosynthesis: Why bother with LH II and LH I? (What are the two called together?
Antenna Complex. Big Antenna Complex means + SA for - expensive proteins needed to create RC. It allows light to be captured well despite small RC.
Anoxic Photosynthesis: What two components are involved in conversion of CO2 into carbohydrates?
- ATP
2. Reducing Power
Anoxic Photosynthesis: ATP is created by process named… This ATP is used later in…
Cyclic Photophosphorylation. Calvin Cycle.
Anoxic Photosynthesis: Explain the 5 steps of Cyclic Photophosphorylation in terms of e-.
- At Bacterial Chlorophyll, light hits and excite e-
- Excited e- is captured by Quniol.
- Quinol transfers e- to Cyt bc to create a proton gradient outside the cell.
- e- is transfered from Cyt bc to Cyt c.
- e- is transfered from Cyt c to Bacterio Chlorophyll, to be recycled again.
Anoxic Photosynthesis: Despite the name Cyclic Photophosphorylation, some e- on Bacteriochlorophyll is removed. For what purpose? Why? Mention NAD/NADPH. How is this replenished?
Reducing CO2 into C6H12O6 requires e-. (Reduction means adding e- gain.) Hence, e- is removed to create NADPH from NAD. However, H2S oxidation allows e- replenishment.
Anoxic Photosynthesis: CO2 –> Carbohydrates; What does it use? What does it produce?
ATP and NADPH from Photosynthesis. It produces C6H12O6.
Anoxic Photosynthesis: What are the 3 stages of Calvin Cycle? What happens? What does this step require?
- Carboxylation. CO2 attached to 5-C sugar molecule (is oxidized) by Rubisco.
- Reduction: CO2-5-C Sugar reduced to CH4. Requires ATP and NADPH.
- Regeneration: Reconstructs 5 C sugar. Requires ATP.
Does Chromatium vinosum grow? How?
By elongation.
Does Chromatium vinosum develop? How?
Nope.
Does Chromatium vinosum reproduce? How?
Binary Fission.
