Borob'eva L I, Cherdyntseva T A, Abilev S K
Mikrobiologiia. 1995 Mar-Apr;64(2):228-33.
It is shown that in the presence of culture liquid and cells of Propionibacterium shermanii, P. pentosaceum, P. thoenii, P. coccoides, P. acnes, Lactobacillus delbrueckii, Streptococcus thermophilus, Str. faecalis, Bifidobacterium bifidum, and Escherichia coli AB 1157 the mutagenicity of 4-nitroquinoline-1-oxide (4-NQO) in Salmonella typhimurium TA 100 decreases significantly. The highest antimutagenic (desmutagenic) activity was found in culture liquid from all strains tested in the logarithmic growth phase; on aging of the cultures their antimutagenic activity decreased. The cells passaged in the medium containing 4-NQO demonstrate a higher antimutagenic activity than the control cells, and this effect is not related to the cell mutation. Young cultures of all studied propionic bacteria and of Str. faecalis release thiol compounds into medium. Thiol accumulation in culture liquid from P. shermanii between 10 and 24 h was accompanied by culture transition to the active growth. Over 24 h thiol content decreased. The maximal thiol accumulation by 24 h coincided with the maximal desmutagenic activity of the culture. It is suggested that desmutagenesis of the bacteria studied towards 4-NQO is connected with their production of reducing (possibly, sulfur-containing) compounds that inactivate electrophilic groups of the mutagen.
结果表明，在存在谢氏丙酸杆菌、戊糖片球菌、索氏丙酸杆菌、球形丙酸杆菌、痤疮丙酸杆菌、德氏乳杆菌、嗜热链球菌、粪肠球菌、双歧双歧杆菌和大肠杆菌AB 1157的培养液及细胞的情况下，鼠伤寒沙门氏菌TA 100中4-硝基喹啉-1-氧化物（4-NQO）的诱变性显著降低。在对数生长期测试的所有菌株的培养液中发现了最高的抗诱变（去诱变）活性；随着培养物老化，它们的抗诱变活性降低。在含有4-NQO的培养基中传代的细胞表现出比对照细胞更高的抗诱变活性，并且这种效应与细胞突变无关。所有研究的丙酸杆菌和粪肠球菌的年轻培养物都会向培养基中释放硫醇化合物。谢氏丙酸杆菌培养液中硫醇在10至24小时之间的积累伴随着培养物向活跃生长的转变。24小时后硫醇含量下降。到24小时时硫醇的最大积累量与培养物的最大去诱变活性一致。有人提出，所研究的细菌对4-NQO的去诱变作用与其产生使诱变剂的亲电基团失活的还原性（可能含硫）化合物有关。
