Fig. 1

Detection and quantification of rmHO-1 in NZ-HO. a A vector map of the lactococcal secretion vector, pNZ8148#2:SEC (left), and schematic representations of gene maps from P _nis to the MCS of pNZ8148#2:SEC (right). P _nis nisin-inducible promoter, SP _usp45 sequence of the signal peptide from the USP45 protein, His-tag 6 × histidine-tag, FXa factor Xa recognition site, MCS multiple cloning site, rep replication gene, cm chloramphenicol acetyltransferase gene, mHO-1 mouse heme oxygenase-1. b, c Gene expression was induced in gmNZ9000 with nisin. Cellular extracts (Cell) and culture supernatants (Sup) were analyzed with SDS-PAGE (b) or western blotting using an anti-His-tag Ab or anti-HO-1 Ab. MW indicates the molecular mass markers (kDa). Gray and black arrows indicate the precursor of secreted rmHO-1 (pre-rmHO-1, 40.5 kDa) and the secreted form of rmHO-1 (rmHO-1, 37.7 kDa), respectively. Representative images from three independent experiments are shown. d mHO-1 in cellular extracts from nisin-induced gmNZ9000 was quantified by ELISA. Data are the mean ± SD (n = 6). nd not detected