Amt reqd for N-terminal sequence?

[John Fox]

In article <1994May25.091849.28879 at waikato.ac.nz>, pjc at waikato.ac.nz (Peter Charlton) says:
>
>Sorry to trouble the net with such a trivial question, but for some reason I
>can't find a single consistent answer.
>What is the minimum amount of protein needed to obtain an N-terminal sequence
>of 5-6 residues?
>
>Many thanks,
>Peter.

For us, the minimum would be about 1 picomole, assuming that the protein is clean.
Difficulties arise when you have multiple prolines a the pro-X bond is abnormally stable.

SODs law does apply in protein sequencing, interesting proteins are always N terminal blocked.