Week 3 Flashcards
What is Thiamine pyrophosphate?
a derivative of vitamin B1
Which organelle is responsible for beta-oxidation of very-long-chain fatty acids?
The peroxisome
What is our total body water percentage?
60% of our weight
Glucose-6-phosphate dehydrogenase deficiency is what type of anemia. What is another name for it? Who does it effect?
hemolytic anemia. favism. It occurs mostly in males.
What other elements in the mitochondria form superoxides?
Flavoproteins
Describe the Fenton and Haber-Weiss reaction
Ferric (Fe+3) iron interacts with superoxide to produce ferrous iron (Fe+2). Ferrous iron then interacts with hydrogen peroxide to form the hydroxyl radical.
The net reaction is the superoxide interacting with hydrogen peroxide to form the hydroxyl radical
Name 2 Uncouplers and define what they do?
Acetylsalicylate (aspirin) and Dinitrophenol interfere with oxidative phosphorylation which results in less ATP produced, and the energy (wasted) turned into heat.
Out of our 60% TBW what is the percent for water in the ICF and ECF
40% ICF
20% ECF
Name 4 fat-soluble antioxidants
Vitamin E, Vitamin A, Ubiquinone and retinoids
Name 4 non-radical but highly reactive oxidants
Ozone, Singlet oxygen, HOCl¯ Hypochlorous Acid, ONOO¯ Peroxynitrite
Cyanide, Carbon monoxide, azide, and cassava root acts where?
Cytochrome oxidase, complex IV
What is ascorbate? What is it used for?
Vitamin C. It is a cofactor for proly hydroxylase and it is soluble vitamin antioxidant.
HIF prolyl hydroxylases require what to be active?
Oxygen, Vitamin C/ascorbate acid, and iron.
What enzyme in the TCA cycle yields GDP?
Succinyl CoA Synthase
Which membrane-bound enzyme complex makes superoxides for lysosomes
NADPH oxidase
Aspirin toxicity causes what?
Uncoupling oxidative phosphorylation.
Atractyloside and Bongkrekate inhibit which complex
complex v, ATP Synthase
What is another name for vitamin E
α-tocopherol
Which enzymes yield NADH in the TCA cycle?
Isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, and malate dehydrogenase
What is another name for vitamin C
Ascorbic acid/ ascorbate,
Name 4 water-soluble antioxidants
Vitamin C, Uric acid, Sulfhydryl compounds, Phytochemicals
What is the indicator dilution equation?
volume=(Mass-Mass Excreted)/ Concentration
What repair mechanism is used to repair double-strand breaks during prophase I? Why?
Homologous recombination (HR). The homologous chromosomes (the tetrad) use each other to repair the DNA. Used during M phase
What decreases the activity of Pyruvate dehydrogenase?
ATP, Acetyl coA, NADH, Citrate, and Malonyl CoA
Is nitric oxide a free radical oxidant?
yes
How are reactive species generated in the mitochondria? What are the conditions?
Complex 1 NADH Hydrogenase will generate when superoxide when oxygen is low or when NADH is abundant.
Given 500 mM NaCl, how to I get the units to be in mOsM/L
Multiply the value by the number of particles in solution which would be 2 for NaCl
Glutathione is made from what amino acids. What is the oxidized form of glutathione
Glutamate, Cysteine, and Glycine. Glutathione peroxidase (GSSG)
What increases the activity of Pyruvate dehydrogenase?
AMP, calcium and Pyruvate
antimycin inhibits what complex
complex III Cytochrome b1-c
How is Microhomology end-joining repair different from HR?
MHEJ uses repetitive DNA (NOT SISTER CHROMATIDS) to repair the break. Used during M phase (also late G2)
complex 1 is inhibited by what?
Rotenone and Amytal
When is Mismatch repair used?
MMR is used during DNA Polymerization by DNA Pol (epsilon, and delta) to proofread and remove by 3’ to 5’ exonuclease activity. MMR occurs during Late S (also early G2)
When is nucleotide excision repair used?
used during G1, S, G2, and G0. NER is the most active form of repairing DNA. Repairs errors larger than a single base.
What would an x-linked recessive disorder look like on a pedigree? Give disease example.
More males affected and NO father to son transmission. ALD
Which proteins are used in mismatch repair
Mut S (MSH) and Mut L (MLH)
Which organelle is responsible for the beta-oxidation of most fatty acids? Where exactly does it occur?
In the mitochondria matrix
Keap1 keeps what transcription factor inactive? How is Keap1 activated (what sensors does it have)?
NRF2. Cysteines on Keap1 become oxidized under when there is a lot of oxidative stress which inactivates keap1 and activates NRF2.
How does ferrous iron react with hydrogen peroxide
It produces the hydroxyl free radical as seen in the Fenton reaction.
What is another name for vitamin A
Carotenoids
When is base excision repair used?
BER is used during G1, S, G2, and G0 for changes in the DNA that are smaller than 1 whole nucleotide. (Such as methylation or bromo-nucleotide)
How can a superoxide effect ferric iron?
Superoxide will reduce ferric iron (Fe+3) to the ferrous iron (Fe+2)
When is Non-homologous end-joining used?
Used for doubled stranded breaks in M phase (late G2 phase also)
What repair is used for DNA with a single break and no loss of nucleotides?
Ligase will conduct the repair.
What is the difference between incidence rates and prevalence rates?
Incidence rates refer to NEW cases. While prevalence rates are ALL cases within a given period.
NADP+ and NADH are converted to NADPH in the mitochondria by what enzyme?
transhydrogenase
What is a symptom of uncouplers?
Hyperthermia
What is the difference between homoplasmic and heteroplasmic
Mutations in mitochondrial DNA can be either homoplasmic. In homoplasmic mutations the mutation is present in all mitochondrial DNA). Whereas in heteroplasmic the mutation is only partially present in mitochondrial DNA.
