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14 Cards in this Set
- Front
- Back
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What is a peroxisome
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A membrane bound organelle found within all cells
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What are the biochemical reactions occurring in peroxisomes
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Catalyzing first steps of plasmalogen synthesis
Beta-ox of FAs (esp. VLCAs) Catalyzing formation of H2O2 Oxidation of bile acid precursors in last step of bile acid synthesis alpha-hydroxylation of phytanyl-CoA |
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What size of fatty acids will peroxisomes degrade/process
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Lengths longer than six carbons
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95% of matrix (?peroxisomal?) enzymes are targeted by what
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Peroxisomal targeting signals (PTS-1)
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What is the significance of PEX5 and PEX7
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Search me?
Something to do with bringing in PTS2 dependent proteins? |
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Describe Zellweger syndrome
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Severe hypotonia, psychomotor delay, seizure, poor sucking
High forehead, large fontanelle, low broad nasal bridge Don't feed well |
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What three proteins would have their transportation effected by a PEX7 mutation
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Alkyl-dihydroxyacetone phosphate synthase
alpha-hydroxylase (phytanoyl CoA hydroxylase) Thiolase |
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What does PEX7 code for
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PTS-2 receptor
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A complete loss of PTS-2 receptor function might result in what
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Decreased plasmalogen biosynthesis
Phytanic acid build-up Decreased FA degradation |
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Can we do without peroxisomes
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No
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What makes plasmalogens "different"
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?We don't know?
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How do enzymes find their way into peroxisomes
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Various pathways (See PEX5 & PEX7 associated pathways)
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What's different about FA oxidation in peroxisomes
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Uses different set of enzymes, reactions use oxygen and produce peroxide
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Can you have too many very long-chain fatty acids
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Yes
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