Better late than never...
For all those interested: Science, (1996) 273:545-708 (Aug. 2nd): a
special Bioinformatics issue. Of specific interest to PPSers: pages
610 (perspectives) and the accompanying article 666-669.
To summarize: the authors use a simplified model for examining protein
folding: a self-repelling 27 aa chain folded into a 3x3x3 cubic lattice.
"Amino acids" are of two kinds: hydrophobic (H) and polar (P). Instead of
looking at "foldability", that is selecting potentially functional
sequences, the authors look at "designability": starting from a given
structure, how many sequences may fold that way. Some structures are
*very* designable, while others are not. The highly designable structures
exhibit "proteinlike" secondary structures. Also, the sequnces for highly
designable structures exhibit well-conserved 'residues'. To quote
"...These results suggest that protein structures are selected in nature
because they are readily designed and stable against mutations, and that
such a selection simultaneously leads to thermodynamic stability".
Discussion, anyone?
Iddo
--Iddo Friedberg ("\''/").___..--''"`-._ Phone: (972)-2-6585459/3 `9_ 9 ) `-. ( ).`-.__.`) email: idoerg@shum.cc.huji.ac.il (_Y_.)' ._ ) `._ `. ``-..-' web: http://www.ls.huji.ac.il/~idoerg _..`--'_..-_/ /--'_.' .' More info: finger idoerg@shum.cc.huji.ac.il Random quote: SCCS, the source motel! Programs check in and never check out! -- Ken Thompson