Problem 6.1 A protein, shown schematically in Figure 6.28, may contain several c

Question

Problem 6.1

A protein, shown schematically in Figure 6.28, may contain several cysteines (represented as light gray balls), which may pair together to form disulfide bonds. For six cysteines, three disulfide bonds can form; the figure shows the pairing arrangement 1-6, 2-5, 3-4. How many different disulfide pairing arrangements are possible?
Derive the general formula for the number of different pairing arrangements when there are n cysteines (and n is even).

0.8 0.6 0.4 t 0.2 0 0 2 3 4 5 oxygen partial pressure (mmHg) 0.8 0.6 0.4 t 0.2 0 0 5 10 15 20 25 SCD4 concentration (nM) 0.8 0.6 0.4 0.2 0 100 102 103 NtrC concentration (nM) Figure 6.28 Physical Biology of the Cell, 2ed. (O Garland Science 2013)

Explanation / Answer

Since there are Six Cysteines and a disulphide bond is formed between two cysteine residues.

So for Six cysteines ,

The possible number of disulphide bond arrangement is (n-1)+ (n-2) + (n-3) + (n-4) + (n-5) where n is the number of cysteines residue.

So for 6 cysteines.

possible Number of disulphide bond arrangement is

i.e = 5 +4+3+2+1 = 15

So a general formulae can be summation of ( N-n) terms, where N = number of cysteines and

n= 1 to N-1.

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---