Schillinger U, Chung H S, Keppler K, Holzapfel W H
Institut für Hygiene und Toxikologie, Bundesforschungsanstalt für Ernährung, Karlsruhe, Germany.
J Appl Microbiol. 1998 Oct;85(4):657-63. doi: 10.1111/j.1365-2672.1998.00573.x.
Nisin is a bacteriocin with a broad antibacterial spectrum including strains of Listeria monocytogenes. Populations of L. monocytogenes, however, frequently contain spontaneous nisin-resistant mutants. When a culture of L. monocytogenes Scott A was exposed to nisin concentrations between 10 and 500 IU ml-1, the initial decrease in viable numbers was followed by regrowth of survivors to nisin. Nisin-resistant mutants of L. monocytogenes Scott A were isolated after a single exposure to nisin at 100 IU ml-1 and were shown to be sensitive to the non-nisin bacteriocins, sakacin A and enterocin B, produced by Lactobacillus sake Lb 706 and Enterococcus faecium BFE 900, respectively. The regrowth of L. monocytogenes Scott A following the initial decrease due to exposure to nisin was prevented by nisin-resistant Lact. sake Lb 706-la and to a somewhat lesser extent, by Ent. faecium BFE 900-6a. Listerial cells surviving nisin action were thus inhibited by the bacteriocin-producing strains that might be used as starter or protective cultures in foods. Growth of a nisin-resistant mutant of L. monocytogenes Scott A (Li3) was also suppressed by the bacteriocinogenic cultures. Use of nisin in combination with a starter culture producing a non-nisin antilisterial bacteriocin may therefore prevent the emergence of nisin-resistant mutants of L. monocytogenes.
乳酸链球菌素是一种具有广泛抗菌谱的细菌素，包括单核细胞增生李斯特菌菌株。然而，单核细胞增生李斯特菌群体中经常含有自发的乳酸链球菌素抗性突变体。当单核细胞增生李斯特菌斯科特A菌株的培养物暴露于10至500国际单位/毫升的乳酸链球菌素浓度下时，活菌数量最初会减少，随后存活菌体会重新生长。单核细胞增生李斯特菌斯科特A菌株在单次暴露于100国际单位/毫升乳酸链球菌素后分离出抗性突变体，结果显示这些突变体对分别由清酒乳杆菌Lb 706和粪肠球菌BFE 900产生的非乳酸链球菌素细菌素——片球菌素A和肠球菌素B敏感。由于暴露于乳酸链球菌素导致最初数量减少后，单核细胞增生李斯特菌斯科特A菌株的重新生长受到了抗乳酸链球菌素的清酒乳杆菌Lb 706-la的抑制，粪肠球菌BFE 900-6a的抑制作用稍弱。因此，在乳酸链球菌素作用下存活的李斯特菌细胞受到了产细菌素菌株的抑制，这些菌株可作为食品中的发酵剂或保护性培养物。产细菌素培养物也抑制了单核细胞增生李斯特菌斯科特A菌株的抗乳酸链球菌素突变体（Li3）的生长。因此，将乳酸链球菌素与产生非乳酸链球菌素抗李斯特菌细菌素的发酵剂培养物联合使用，可能会防止单核细胞增生李斯特菌抗乳酸链球菌素突变体的出现。
