Lecture 15, 10/10; Respiration, Fermentation, DNA replication, etc.

Here is the recording for today's lecture.

• Wednesday Oct 17 dr. maybrook comes in to teach
-Read the chapters – maybrook will follow syllabus
• Submit lecture paper in a week
• Big paper mon nov 19
-Outline
-Abstract
-1 figure (labeled at bottom)
-1 table (labeled at top)
• he will probably return after thanksgiving

This is what I got out of the lecture from 10/10. I would suggest listening to the lecture and checking the book/handouts because there were several parts that I was shady on.

• • Discussing glycolisis (handout 10/5)
• Glucose C6H12O6. Aerobes and anaerobes have to use glycoliysis to get to pyruvate. It is an anaerobic function, happens in the cytoplasm. What does it do? Uses two ATP’s to make energy. Once you get to a diphosphate you will split it into things you can use like reducing power, NADH. Produce four ATP → net 2. This is the two that anaerobic organisms get.
• Glycolosis C6 glucose going to two pyruvates (pyruvates are the central hub of the wheel).
• Krebs cycle (needs oxygen) – takes two C3’s (pyruvate) and breaks it down to 6 CO2’s. It deals with carbon break down. For energetics (p229 in text) you have to have GTP in the same triphosphate. That is why they convert GTP to ATP. Each “turn of the wheel” you get a GTP that is equal to an ATP. We “turn the wheel” twice (two pyruvates). Gives us lots of reducing power: NADH (4 per turn), FADH2 (1 per turn). This reducing power proceeds to the electron transport system.
• E. coli gets 38 ATP’s we get 36.
• • Understand Respiration
• • C6H12O6 + CO2 + 6 Oxygens = 6CO2 + 6H2O (comes off at the end of the cytochrome chain) + Energy (ATP)
• If the organism has oxygen and is an aerobe or a facaltative organism it will do these things for their energy. Both anaerobes and facaltative first get two ATP’s at the glycolosis pathway/substrate level phosphorilation. We get most of our energy from oxidative phosphorilation.
• • fermentation – anaerobic metabolism of sugars (handout 10/5 page 4)
• glucose → pyruvate is glycolosis. All fermentations involve glucose to pyruvate and then pyruvate to acids alcholos and gases.
• yeast or alcoholic fermentation – saccharomyces cerevisiae
• bacterial fermentationts
• • homolactic fermentation – glucose goes to pyruvate and then pyruvate goes to lactic acid. Sour milk organisms → streptococcus lactis (makes sour cream). All streps do this type of fermentation.
• • heterolactic fermentation – produces lactic acid, ethyl alcohol and CO2. Ex. lactobacillus brevis (found around the nipple). Newborns poop goes white to yellow and smells like acid due to this organism. Leuconostoc mesenteroides
• • clostridial fermentation – butyric acid (smells terrible, part of puke).
• • propionic acid fermentation – propionibacterium shermanii. Associated with swiss cheese. The taste, and smell is propionic acid.
• • mixed acid fermentation – Escherichia coli and Enterobacter (found on plants) aergones both do mixed acid fermentation.
• natural fermentation
• • silage – matabiosis=sequential growth. One group dies and then the next starts growing.
• • sourkraut - metabiosis
• chop up cabbage and add 2.5% sodium chloride
• [(?not sure if I got this right?) mixed acid → heterolactic → lactobacillus plantarum → acidic cabbage. ?]
• • protein degradation (p3 of handout 10/5)
• large proteins (gelatin, kasin(sp?)) broken down by extracellular enzymes. Organism produces a protease – if it breaks down gelatin it is a gelintinase and if it breaks down kasin(sp?) it is a kasinase(sp?). B. sub has strong extracellular enzymes that we even use them in detergents.
• After you break the big proteins to amino acids there are organisms that break down individual amino acids like tryptophan (broken down by tryptophanase). Indole smells – rotting meat. – organisms that break down original amino acids like tryptopha.
• Sulfar Containing amino acids → h25. Proteus vulgaris
• decay (aerobic) decomposition of proteins is how sewage treatment works. Putrefaction - anaerobic decomposition of proteins.
• • Applied food microbiology (p5 handout 10/5
• bread
• wine and beer
• vinegar – acetobacter acetii
• cheese – molds ripen cheese (penicilium).
• Curds from producing lactic acid. Organisms responsible: streptococcus lactis and streptococcus cremoris.
• Yogurt
• Soy sauce – double fermentation
• • FUEL
• zymomonas mobilis – produces twice as much ethonal as yeast
• • enzymes – usually come from bacillus or molds
• protease – helps break down proteins
• amylase
• we are currently using penicillium chrysogenum to produce penicillin. It is then altered to get different types of penicillin.
• • P7 of handout from 10/5
• kefir – lightly alchoholic fermented milk drink
• San Francisco sourdough – tastes sour because of the lactic acid. Lactobacillus sanfrancisco
• • last page of handout from 10/5
• bacitracin – made by particular strain of B. sub
• citric acid – used for soda made by Aspergillus and Candida.
• • DNA replication (p6 of handout from 10/5)
• Inside E. coli DNA is coiled over itself many times, this is called supercoiling. To get it uncoiled we use a gyrase, it undoes supercoiling. Once it is straightened out you have got to unzip the DNA which is done by helicase. Make an RNA first by a primase and then start adding on to the RNA primer. Then you take the RNA primer out with polymerase I. With the new strands of DNA you put them together with DNA ligase.
• • Material for exam 2 ends here. -------------------