| 摘要 |
<p>The invention relates to a recombinant DNA molecule coding for a polypeptide having a phytase activity after expression in a procaryotic or eucaryotic host cell. Said recombinant DNA molecule comprises a DNA sequence selected from a) DNA sequences that have been obtained by variations of the mature wild type E.coli phytase sequence, at least one amino acid being mutated between positions 189 and 211 and/or between positions 137 and 152 in comparison to the wild type sequence; b) DNA sequences having a homology of between 70 % and 100 % in relation to the sequences according to a); and c) DNA sequences related to the sequences according to a) and b) as a result of the degeneracy of the genetic code. During the expression of the recombinant DNA molecule in an adapted host cell, said recombinant DNA molecule is associated with an increased activity of the thus coded protein in the culture supernatant. The invention also relates to thus coded proteins.</p> |
