| 摘要 |
A process for preparing a consensus protein is described. The process is characterized by the following steps: a) at least three, preferably four amino acid sequences are aligned by any standard alignment program known in the art; b) amino acids at the same position according to such alignment are compared regarding their evolutionary similarity by any standard program known in the art, whereas the degree of similarity provided by such a program which defines the least similarity of the amino acids that is used for the determination of an amino acid of corresponding positions is set to a less stringent number and the parameters are set in such a way that it is possible for the program to determine from only 2 identical amino acids at a corresponding position an amino acid for the consensus protein; however, if among the compared amino acid sequences are sequences that show a much higher degree of similarity to each other than to the residual sequences, these sequences are represented by their consensus sequence determined as defined in the same way as in the present process for the consensus sequence of the consensus protein or a vote weight of 1 divided by the number of such sequences is assigned to every of those sequences. c) in case no common amino acid at a defined position is identified by the program, any of the amino acids, preferably the most frequent amino acid of all such sequences is selected; d) once the consensus sequence has been defined, such sequence is back-translate d into a DNA sequence, preferably by using a codon frequency table of the organism in which expression should take place; e) the DNA sequence is synthesized by methods known in the art and used either integrated into a suitable expression vector or by itself to transform an appropriate host cell; f) the transformed host cell is grown under suitable culture conditions and the consensus protein is isolated from the host cell or its culture medium by methods known in the art. |
