how to get secondary structure from DSSP?

Here is Biopython’s DSSP code, with typical use shown near the top. It is not difficult to extract this information on your own by reading contents of column 17 of the DSSP output, following this line:

  #  RESIDUE AA STRUCTURE BP1 BP2  ACC     N-H-->O    O-->H-N    N-H-->O    O-->H-N    TCO  KAPPA ALPHA  PHI   PSI    X-CA   Y-CA   Z-CA

You may want to convert the 8-letter designation utilized by DSSP into 3 letters – space (or empty character '') is considered to be C. Typical conversion schemes are:

SS-Scheme 1: H,G,I->H ; E,B->E ; T,S->C
SS-Scheme 2: H,G->H ; E,B->E ; I,T,S->C    I think this is most common
SS-Scheme 3: H,G->H ; E->E ; I,B,T,S->C
SS-Scheme 4: H->H ; E,B->E ; G,I,T,S->C
SS-Scheme 5: H->H ; E->E ; G,I,B,T,S->C

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