TY - JOUR
T1 - Molecular Diagnostics of Arthroconidial Yeasts, Frequent Pulmonary Opportunists
AU - Kaplan, Engin
AU - Al-Hatmi, Abdullah M S
AU - Ilkit, Macit
AU - Gerrits van den Ende, A H G
AU - Hagen, Ferry
AU - Meis, Jacques F
AU - de Hoog, G Sybren
N1 - Copyright © 2017 American Society for Microbiology.
PY - 2018/1
Y1 - 2018/1
N2 - Magnusiomyces capitatus and Saprochaete clavata are members of the clade of arthroconidial yeasts that represent emerging opportunistic pulmonary pathogens in immunocompromised patients. Given that standard ribosomal DNA (rDNA) identification often provides confusing results, in this study, we analyzed 34 isolates with the goal of finding new genetic markers for classification using multilocus sequencing and amplified fragment length polymorphism (AFLP). The interspecific similarity obtained using rDNA markers (the internal transcribed spacer [ITS] and large subunit regions) was in the range of 96 to 99%, whereas that obtained using protein-coding loci (Rbp2, Act, and Tef1α) was lower at 89.4 to 95.2%. Ultimately, Rbp2 was selected as the best marker for species distinction. On the basis of cloned ITS data, some strains proved to be misidentified in comparison with the identities obtained with phenotypic characters, protein sequences, and AFLP profiles, indicating that different copies of the ribosomal operon were present in a single species. Antifungal susceptibility testing revealed that voriconazole had the lowest MIC against M. capitatus, while amphotericin B had the lowest MIC against S. clavata Both species exhibited in vitro resistance to fluconazole and micafungin.
AB - Magnusiomyces capitatus and Saprochaete clavata are members of the clade of arthroconidial yeasts that represent emerging opportunistic pulmonary pathogens in immunocompromised patients. Given that standard ribosomal DNA (rDNA) identification often provides confusing results, in this study, we analyzed 34 isolates with the goal of finding new genetic markers for classification using multilocus sequencing and amplified fragment length polymorphism (AFLP). The interspecific similarity obtained using rDNA markers (the internal transcribed spacer [ITS] and large subunit regions) was in the range of 96 to 99%, whereas that obtained using protein-coding loci (Rbp2, Act, and Tef1α) was lower at 89.4 to 95.2%. Ultimately, Rbp2 was selected as the best marker for species distinction. On the basis of cloned ITS data, some strains proved to be misidentified in comparison with the identities obtained with phenotypic characters, protein sequences, and AFLP profiles, indicating that different copies of the ribosomal operon were present in a single species. Antifungal susceptibility testing revealed that voriconazole had the lowest MIC against M. capitatus, while amphotericin B had the lowest MIC against S. clavata Both species exhibited in vitro resistance to fluconazole and micafungin.
U2 - 10.1128/JCM.01427-17
DO - 10.1128/JCM.01427-17
M3 - Article
C2 - 29070656
SN - 0095-1137
VL - 56
JO - Journal of Clinical Microbiology
JF - Journal of Clinical Microbiology
IS - 1
ER -