Meyer Jean-Marie, Geoffroy Valérie A, Baida Nader, Gardan Louis, Izard Daniel, Lemanceau Philippe, Achouak Wafa, Palleroni Norberto J
Laboratoire de Microbiologie et de Génétique, CNRS/Université Louis-Pasteur FRE 2326, 67000 Strasbourg, France.
Appl Environ Microbiol. 2002 Jun;68(6):2745-53. doi: 10.1128/AEM.68.6.2745-2753.2002.
A total of 301 strains of fluorescent pseudomonads previously characterized by conventional phenotypic and/or genomic taxonomic methods were analyzed through siderotyping, i.e., by the isoelectrophoretic characterization of their main siderophores and pyoverdines and determination of the pyoverdine-mediated iron uptake specificity of the strains. As a general rule, strains within a well-circumscribed taxonomic group, namely the species Pseudomonas brassicacearum, Pseudomonas fuscovaginae, Pseudomonas jessenii, Pseudomonas mandelii, Pseudomonas monteilii, "Pseudomonas mosselii," "Pseudomonas palleronii," Pseudomonas rhodesiae, "Pseudomonas salomonii," Pseudomonas syringae, Pseudomonas thivervalensis, Pseudomonas tolaasii, and Pseudomonas veronii and the genomospecies FP1, FP2, and FP3 produced an identical pyoverdine which, in addition, was characteristic of the group, since it was structurally different from the pyoverdines produced by the other groups. In contrast, 28 strains belonging to the notoriously heterogeneous Pseudomonas fluorescens species were characterized by great heterogeneity at the pyoverdine level. The study of 23 partially characterized phenotypic clusters demonstrated that siderotyping is very useful in suggesting correlations between clusters and well-defined species and in detecting misclassified individual strains, as verified by DNA-DNA hybridization. The usefulness of siderotyping as a determinative tool was extended to the nonfluorescent species Pseudomonas corrugata, Pseudomonas frederiksbergensis, Pseudomonas graminis, and Pseudomonas plecoglossicida, which were seen to have an identical species-specific siderophore system and thus were easily differentiated from one another. Thus, the fast, accurate, and easy-to-perform siderotyping method compares favorably with the usual phenotypic and genomic methods presently necessary for accurate identification of pseudomonads at the species level.
通过铁载体分型法，即通过对荧光假单胞菌主要铁载体和绿脓菌素进行等电聚焦表征以及测定菌株的绿脓菌素介导的铁摄取特异性，对之前采用传统表型和/或基因组分类方法鉴定的总共301株荧光假单胞菌进行了分析。一般来说，在一个界定明确的分类群内，即油菜假单胞菌、褐鞘假单胞菌、耶氏假单胞菌、曼氏假单胞菌、蒙氏假单胞菌、“莫氏假单胞菌”、“帕氏假单胞菌”、罗得西亚假单胞菌、“萨氏假单胞菌”、丁香假单胞菌、蒂氏假单胞菌、托氏假单胞菌、维氏假单胞菌以及基因组种FP1、FP2和FP3中的菌株产生相同的绿脓菌素，此外，该绿脓菌素是该分类群的特征性物质，因为其结构与其他分类群产生的绿脓菌素不同。相比之下，属于众所周知的异质性荧光假单胞菌物种的28株菌株在绿脓菌素水平上表现出很大的异质性。对23个部分表征的表型聚类的研究表明，铁载体分型法在提示聚类与明确物种之间的相关性以及检测误分类的单株菌株方面非常有用，这一点已通过DNA-DNA杂交得到验证。铁载体分型法作为一种鉴定工具的实用性扩展到了非荧光物种皱叶假单胞菌、弗雷德里克伯格假单胞菌、禾本科假单胞菌和鳗弧假单胞菌，这些物种被发现具有相同的物种特异性铁载体系统，因此很容易相互区分。因此，快速、准确且易于操作的铁载体分型法与目前在物种水平上准确鉴定假单胞菌所需的常规表型和基因组方法相比具有优势。
