Müller H E
Zentralbl Bakteriol Mikrobiol Hyg A. 1986 Feb;261(1):1-11. doi: 10.1016/s0176-6724(86)80058-x.
The indole reaction is performed in various modifications with regard both to the reagents and to the media used. Especially the medium has hitherto attracted little attention and there are divergent recommendations for its composition. The comparison of some broths without and with addition of tryptophan after incubation with different indole-positive species revealed that tryptone without tryptophan yielded stronger reactions than with tryptophan added. Other broths showed stronger reactions with tryptophan. Investigations revealed that numerous indole-positive as well as indole-negative species possess an enzyme system degrading indole. It is induced after one or two days of incubation and acts slowly. All species of the Morganella-Proteus-Providencia group possess it, as does Serratia. Some other species show different characteristics. The production of indole from peptone containing tryptophan and the degradation of indole by such species of bacteria are due to figures showing one or more peaks depending on time. Any false indole reactions described up to now may also be explained by the antagonism of the two enzyme systems. Therefore, the indole reaction should be standardized with regard to the medium used to avoid some of these difficulties.
吲哚反应在试剂和所用培养基方面有多种改进形式。特别是培养基迄今为止很少受到关注，对于其成分有不同的建议。在与不同的吲哚阳性菌培养后，对一些添加和未添加色氨酸的肉汤进行比较，结果显示不含色氨酸的胰蛋白胨产生的反应比添加色氨酸的更强。其他肉汤在添加色氨酸后反应更强。研究表明，许多吲哚阳性菌和吲哚阴性菌都拥有降解吲哚的酶系统。它在培养一到两天后被诱导，作用缓慢。摩根菌 - 变形杆菌 - 普罗威登斯菌属的所有菌种以及沙雷菌都有这种酶系统。其他一些菌种表现出不同的特性。含有色氨酸的蛋白胨产生吲哚以及此类细菌对吲哚的降解取决于随时间出现的一个或多个峰值。迄今为止描述的任何假吲哚反应也可能由这两种酶系统的拮抗作用来解释。因此，应针对所用培养基对吲哚反应进行标准化，以避免其中一些困难。
