Impact of Molecular Diagnostics in Mycology Laboratory. Yew Su Mei1, Kuan Chee Sian1, Na Shiang Ling1, Harvinder Kaur Lakhbeer Singh1, Ng Kee Peng1.
Impact of Molecular Diagnostics in Mycology Laboratory
Introduction
Yew Su Mei1, Kuan Chee Sian1, Na Shiang Ling1, Harvinder Kaur Lakhbeer Singh1, Ng Kee Peng1 1Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
• Fungal infections are increasing [1] • Conventional fungal identification methods - direct microscopy and histopathology • Drawbacks: a) inability to accurately identify fungal species b) novel species • Study aims: Molecular identification and phylogenetic analysis aid in fungal identification
Methodology
DNA extraction
Polymerase chain reaction (PCR)
Sanger sequencing
BLAST
Phyogenetic analysis
~ internal transcribe spacer (ITS) ~ small subunit rRNA (SSU) ~ large subunit rRNA (LSU)
Results 1. Dematiaceous fungi study
2. Rare yeast species identification I) Quambalaria cyanescens UM 1095 a)
b)
c)
Figure 2: a) Multilocus phylogenetic ana;ysis using ITS and D1/D2 domain nucleotide sequences in the identification of Q. cyanescens UM 1095. b) colonial features and c) micrograph of UM 1095 [3]
II) Metschnikowia sp.UM 1034 a)
Figure 1: ITS-based phylogenetic analysis of dematiaceous fungi isolated in UMMC [2]
c)
b)
Conclusion The use of molecular and phylogenetic approach would facilitate the diagnosis of causative agent in causing infection
Acknowledgement This study was supported by High Impact Research MoE Grant UM.C/625/1/HIR/MOHE/MED/31 (Account no. H-20001-00E000070) from the Ministry of Education Malaysia
Figure3: a) colonial features and micrograph of UM 1034. b) ITSbased and c) D1/D2 domain-based phylogenetic tree
References 1. Pfaller, .M.A. and Diekema, D.J. (2010). Epidemiology of Invasive Mycoses in North America. Critical Reviews in Microbiology 36: 1-53. 2. Yew SM, Chan CL, Lee KW, Na SL, Tan R, Hoh CC, Yee WY, Ngeow YF, Ng KP (2014) A five-year survey of dematiaceous fungi in a tropical hospital reveals potential opportunistic species. PLoS One. 9(8):e104352. 3. Kuan CS, Yew SM, Toh YF, Chan CL, Ngeow YF, et al. (2015) Identification and Characterization of a Rare Fungus, Quambalaria cyanescens Isolated from the Peritoneal Fluid of a Patient after Nocturnal Intermittent Peritoneal Dialysis. PLoS One. 10(12):e0145932
