Lecture 34 - Amino Acid Metabolism II Flashcards Preview

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Flashcards in Lecture 34 - Amino Acid Metabolism II Deck (25):
1

Heme synthesis involves the reaction of glycine and _________.

succinyl-CoA

2

The production of heme from succinyl CoA and glycine begins with the rate determining step. What enzyme controls this step?

delta-aminolevulinate synthase

3

delta-aminolevulinate synthase controls heme synthesis, and requires what co-factor? A. succinyl-CoA B. Vitamin B6 C. Vitamin B3 D. Glycine

B. Vitamin B6

4

The production of heme requires a cyclic ring structure, that is linearized with other porphobilinogen rings. What enzyme catalyzes this reaction? A. ALA dehydratase B. porphobilinogen deaminase C. uroporphyrinogen III synthase D. Uroporphorynogen decarboxylase

B. porphobilinogen deaminase (the removal of an NH3 allows for the formation of a linear terapyrrole)

5

Production of the initial porphyrinogen ring is catalyzed by what enzyme? A. uroporphyrinogen III synthase B. porphobilinogen deaminase C. ALA dehydratase D. Uroporphorynogen decarboxylase

A. uroporphyrinogen III synthase

6

A patient presents with neuropsychiatric symptoms, as well as fluorescent crystals on the skin. When exposed to UV radiation, the patient complains of severe pain. You believe they are suffering from a heme synthesis disorder. What condition is described here, and what enzyme is deficient?

Disease: acute intermittent porphyria Enzyme: porphobilinogen deaminase; unable to produce linear tetrapyrrole

7

Congenital erythropoetic prophyria is an enzyme deficiency that results in erythrocyte damage. UV radiation may result in the formation of painful vesicles and that rupture. What enzyme is deficient?

uroporphyrinogen III synthase

8

The breakdown of heme begins when heme is converted to _________. A. Biliverdin B. Bilirubin diglucuronide C. Bilirubin

A. biliverdin

9

The breakdown of biliverdin produces ___________. A. Additional biliverdin B. Bilirubin diglucuronide C. Bilirubin

C. bilirubin

10

Bilirubin is produced in the ____ to form bilirubin diglucuronide. A. bloodstream B. intestines C. liver

C. liver

11

The liver changes bilirubin to bilirubin diglucuronide using what enzyme?

UDP-glucuronide transferase

12

Outline the breakdown of heme, including where breakdown occurs, the products, and how they are excreted. 

A image thumb
13

Some premature infants require "bili-lights" after birth. For what reason is this treatment used?

Bilirubin is removed in utero from the fetus by the placenta. After birth, the child's liver begins the processing of bilirubin. As it takes some time for this to occur, free bilirubin may lead to jaundice. Bili lights stimulate the removal of unconjugated bilirubin by stimulating the release of water soluble bilirubin. 

14

What molcules are serine deriviatives? 

Sphingosine (contains -OH in side chain)

15

What molecule is histidine derived?

Histamine

16

What molecules are tyrosine derivatives?

Thyroxine and epinephrine (contain aromatic rings with -OH group)

17

What molecules are tryptophan derivatives?

Serotonin

Nicotinamide

18

Nitric oxide is derived from what amino acid?

arginine

19

Nitric oxide synthase is the enzyme for nitric oxide synthesis. What cofactor is required?

BH4 

20

This produces Nitric Oxide as a neurotransmitter.

n-NOS

21

This produces Nitric Oxide as part of the macrophage's role in free-radical mediated pathogen destruction.

i-NOS

22

This produces Nitric Oxide as a vasodilator

e-NOS (endothelial NO synthase)

23

PKU produces ketone bodies that result in neurological disfunction. Which PKU type results form enzyme deficiency?

Type I

24

The glutathione system acts to protect the body from free radicals. What ion is used as the actual anti-oxidant?

Selenium

25

PKU produces ketone bodies that may result in neurological disfunction.  Type II sees what defiency in the chemical process?

BH4