The study integrates knowledge resulting from structure-activity relationships analysis of amino acids with respect to the characterization of alpha1 and alpha2 type I collagen chains. Specifically, 15 amino acids and 14 properties were investigated and their structure-activity relationship models were obtained. The models were integrated into a web application and were used to predict the properties of a set of six amino acids. The similarities in alpha1 and alpha2 type I collagen chains has been investigated starting from the observed and predicted properties of amino acids by using two-step cluster analysis.