Agarose well diffusion assay, whereby L. lactis HP/pNZ44 and strains expressing nsuFEG and spiFEG were challenged under adverse growth conditions with nisins A, F, Z, Q, and U. Asterisks indicate zone diameters which were significantly smaller by Student's t test (P < 0.0005) than that found in L. lactis HP, hence implying the protective capabilities of these genes.