Disulphide bonds and cytoplasmic proteins?

[Dr. Mrigank]

Hi netters,

We are looking for an answer for a debate. It started in a group discussion
where a statment was made "..Only protein that enter the secretory pathway have
disulfide bonds.." This was disputed. We looked up in literature and found "..
Of proteins which never leave the parent cell a very few posses disulfide
bridges.." Principle of Protein Structure  by S.E.Schultz and Schirmer (1978)
Springer-Verlag, p. 54. 

Now we would like to know if there are any cytoplasmic proteins which have a
disufide bonds? If so, what are the examples? 

Are these bonds in cytoplasmic proteins artifacts (like air oxidation during
lysis) ?

How are these bonds formed in the cytoplasm? are there any PDI like enzymes ?

-- 
Dr. Mrigank                       \/Phone  +91 172 45004 x216
Institute of Microbial Technology /\Email:  mrigank at imtech.ernet.in
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