Send to:

Choose Destination
See comment in PubMed Commons below
Int J Syst Evol Microbiol. 2013 Mar;63(Pt 3):1056-61. doi: 10.1099/ijs.0.039990-0. Epub 2012 Jun 15.

Nocardia amikacinitolerans sp. nov., an amikacin-resistant human pathogen.

Author information

  • 1Bacterial Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Disease, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.


Five nocardioform isolates from human clinical sources were evaluated. Analysis of the nearly full-length 16S rRNA gene showed 99.9-100 % similarity among the strains. The results of a comparative phylogenetic analysis of the 16S rRNA gene sequences indicated that the isolates belonged to the genus Nocardia. Phenotypic and molecular analyses were performed on the clinical isolates. Traditional phenotypic analyses included morphological, biochemical/physiological, chemotaxonomic and antimicrobial susceptibility profiling. Molecular studies included 1441-bp 16S rRNA and 1246-bp gyrB gene sequence analyses, as well as DNA-DNA hybridizations. Biochemical analysis failed to differentiate the putative novel species from its phylogenetic neighbours; however, molecular studies were able to distinguish the patient strains and confirm them as members of a single species. Based on 16S rRNA gene sequence analysis, similarity between the isolates and their closest relatives (type strains of Nocardia araoensis, N. arthritidis, N. beijingensis and N. niwae) was ≤99.3 %. Analysis of partial gyrB gene sequences showed 98-99.7 % relatedness among the isolates. Nocardia lijiangensis and N. xishanensis were the closest related species to the isolates based on gyrB gene sequence analysis, and their type strains showed 95.7 and 95.3 % similarity, respectively, to strain W9988(T). Resistance to amikacin and molecular analyses, including DNA-DNA hybridization, distinguished the five patient strains from their phylogenetic neighbours, and the results of this polyphasic study indicated the existence of a novel species of Nocardia, for which we propose the name Nocardia amikacinitolerans sp. nov., with strain W9988(T) ( = DSM 45539(T)  = CCUG 59655(T)) as the type strain.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Loading ...
    Write to the Help Desk