Frequency and Markov chain analysis of amino-acid sequences of human glutathione reductase.

The amino-acid sequence of human glutathione reductase was measured according to two- and three-amino-acid sequences. The measured frequency and probability were compared with predicted frequency and probability. Of 477 two-amino-acid sequences in human glutathione reductase, 176 (36.897%) and 90 (18.868%) sequences can be explained by the predicted frequency and the predicted probability according to a purely random mechanism. Of 477 measured first Markov transition probabilities for the second amino acid in two-amino-acid sequences, 1 (0.210%) measured first Markov transition probability matches the predicted conditional probability and can therefore be explained by a purely random mechanism. No more than two-amino-acid sequences can be explained by a purely random mechanism. Copyright 2000 Academic Press.