[New 3D amino acid structure descriptors and its application to the polypeptide QSAR].
OBJECTIVE
To establish a new amino acid structure descriptor that can be applied to polypeptide QSAR studies.


METHODS
The new amino acid structure descriptor c-scales were derived from a principal components analysis of 167 amino acid structure descriptor indexes by theoretic calculation. The c1,c2,c3-scales were related to 3D structural features of amino acid such as steric, electronic and conformation properties etc. G/PLS regression method was used to find out the relationship between the c-scales and the biological activity and developed QSAR models of the polypeptides.


RESULTS
Using the established method, we developed accordingly QSAR models of Bitter tasting dipeptide, ACE inhibitors and bradykinin-potentiating pentapeptides and their r2 and XV-r2 were more than 0.70.


CONCLUSIONS
The c-scales can quantitatively describe the 3D structural features of any coded and non-coded amino acid and can be used to establish a QSAR model of good predictability.
Ding
Jun-jie
JJ
Beijing Institute of Pharmaceutical Chemistry, Beijing 102205, China. dingxq@cetin.net.cn
Ding
Xiao-qin
XQ
Zhao
Li-feng
LF
Chen
Ji-sheng
JS
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D001920:Bradykinin / Q000494:pharmacology; D016018:Least-Squares Analysis; D010455:Peptides / Q000737:chemistry* / Q000494:pharmacology; D025341:Principal Component Analysis; D011487:Protein Conformation; D021281:Quantitative Structure-Activity Relationship; D013329:Structure-Activity Relationship
D000596:Amino Acids; D000806:Angiotensin-Converting Enzyme Inhibitors; D010455:Peptides; D001920:Bradykinin