Área de Microbiología, Dpto. de Biología Molecular, Fac. CC. Biológicas y Ambientales, Campus de Vegazana s/n, Universidad de León, 24071 León, Spain.
Instituto de Biotecnología de León (INBIOTEC), Parque Científico de León, Avda. Real, no. 1, 24006 León, Spain.
Int J Syst Evol Microbiol. 2011 May;61(Pt 5):1084-1088. doi: 10.1099/ijs.0.024273-0. Epub 2010 Jun 4.
The number of tacrolimus (FK506)-producing isolates has increased remarkably because of the clinical importance of tacrolimus as an immunosuppressant. However, the taxonomy of several of these isolates has not been studied. The taxonomic status of strain ATCC 55098(T), a tacrolimus-producing strain, was determined in this study. The genotypic, phenotypic and chemotaxonomic properties were consistent with the inclusion of strain ATCC 55098(T) in the genus Streptomyces. The 16S rRNA gene sequence of strain ATCC 55098(T) was determined and used to generate phylogenetic trees with corresponding sequences of the most closely related type strains (≥ 98 % 16S rRNA gene sequence similarity) of species of the genus Streptomyces. Strain ATCC 55098(T) formed a distinct phylogenetic branch adjacent to a cluster comprising Streptomyces fulvissimus NBRC 13482(T) and Streptomyces flavofungini NBRC 13371(T). However, morphological and physiological tests and DNA-DNA relatedness distinguished strain ATCC 55098(T) from its closest phylogenetic neighbours. On the basis of these results, strain ATCC 55098(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces tacrolimicus sp. nov. is proposed. The type strain is ATCC 55098(T) ( = CECT 7664(T)).
由于他克莫司（FK506）作为免疫抑制剂的临床重要性，产生他克莫司的分离株的数量显著增加。然而，其中一些分离株的分类尚未得到研究。本研究旨在确定产生他克莫司的菌株 ATCC 55098（T）的分类地位。该菌株的基因型、表型和化学生态特征与将 ATCC 55098（T）菌株归入链霉菌属一致。测定了 ATCC 55098（T）菌株的 16S rRNA 基因序列，并与链霉菌属中最密切相关的模式菌株（≥98% 16S rRNA 基因序列相似性）的相应序列生成系统发育树。ATCC 55098（T）菌株形成了一个独特的系统发育分支，与包含 Streptomyces fulvissimus NBRC 13482（T）和 Streptomyces flavofungini NBRC 13371（T）的聚类相邻。然而，形态学和生理学测试以及 DNA-DNA 同源性将 ATCC 55098（T）菌株与其最接近的系统发育近邻区分开来。基于这些结果，ATCC 55098（T）菌株代表了链霉菌属的一个新种，建议将其命名为 Streptomyces tacrolimicus sp. nov.。其模式菌株为 ATCC 55098（T）（ = CECT 7664（T））。
