Figure 1.
A - Nisin A mature peptide, B - AAA Producer (Deferred Antagonism Assay).
The structure of the mature nisin A peptide and the zone of inhibition exhibited by the nisin A derivative, AAA. Panel A depicts the amino acid changes that produce the AAA derivative in the nisin ‘hinge’ region. The modified amino acids dehydroalanine and dehydrobutyrine are denoted as Dha and Dhb respectively with the five (β-methyl)lanthionine rings labelled A to E. Panel B depicts the zones of inhibition produced by L. lactis NZ9800 pDF05(left) and AAA ‘hinge’ variant (right) against L. lactis HP.
Table 1.
Plasmids & strains used in used in this study.
Table 2.
Oligonucleotides used in this study.
Table 3.
Nisin A ‘hinge’ variants with enhanced bioactivity identified through the initial screen.
Table 4.
Frequency with which amino acids are located at each hinge site among the derivatives presented in Table 3.
Table 5.
Actual and expected frequencies of hinge amino acids from randomly selected representatives of the hinge mutant bank.
Table 6.
Deferred Antagonism and Specific Activity Results.