IT - Metals II

Question 1

What are 2 properties of D-group elements?

Answer 1

1. Have multiple oxidation states
2. Sizes don’t vary much

Question 2

What are iron-sulfur clusters?

Answer 2

A complex made out of coordinating sulfur and iron molecules. [4Fe-4S]
* Variable oxidation states as electrons shuffle in and out

Question 3

What does a Pourboix diagram show?

Answer 3

The electrochemical stability for different redox states of an element as a function of pH

Question 4

What bond is frequent in d-metals?

Answer 4

Co-ordinate bonds

Question 5

What are metalloenzymes?

Answer 5

A broad group of enzymes that use a metal cation as a cofactor in the enzyme active site

Question 6

What is the structure of Carbonic anhydrase?

Answer 6

3x Histidine co-ordinated to Zn2+

Question 7

What are 3 uses of zinc in enzyme catalysis?

Answer 7

1. Lewis acid in carboxy-peptidases
2. Carbonic anhydrase
3. Beta-lactamase

Question 8

What are 3 uses of Mg2+ in metalloenzymes?

Answer 8

1. RuBisCO (photosynthesis)
2. ATPases (kinases)
3. Polymerases

Question 9

What is the definition of a transition metal/

Answer 9

An element that has an incomplete d-shell either in its neutral state or its ions

Zn is not a transition metal

Question 10

Where is Molybdenum needed?

Answer 10

In 50 enzymes as a cofactor

Question 11

Where is cobalt present in the body?

Answer 11

In vitamin B12

Question 12

1. What generates Co(II)?
2. What restores Co(III)?

Answer 12

1. Oxidative stress
2. Methionine Synthase Reductase