Modified Protocol for Yeast Identification Using Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry

Janet W. S. Cheng¹, Yit Er Tang¹, Roland Jureen¹, Raymond T.P. Lin¹ and Jeanette W.P. Teo^1,

¹Department of Laboratory Medicine, Microbiology Unit, National University Hospital, Singapore, Republic of Singapore

Cite this paper:
Janet W. S. Cheng, Yit Er Tang, Roland Jureen, Raymond T.P. Lin and Jeanette W.P. Teo. Modified Protocol for Yeast Identification Using Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry. American Journal of Microbiological Research. 2013; 1(4):71-73. doi: 10.12691/ajmr-1-4-2

Abstract

Advances in Matrix-assisted Laser Desorption Ionization–time of Flight Mass Spectrometry (MALDI-ToF MS) identification methods have greatly facilitated the rapid identification of yeasts. We validate the use of a shorter on-plate extraction method as well as a lower score cutoff value on the Bruker Biotyper. Overall, when the on-plate extraction method was used together with a score cutoff of > 1.7, a total of 151 of 187 (81%) Candida isolates were correctly identified. At species level, almost 100% of C. krusei and C. albicans isolates were correctly identified. We find the revised protocol to be effective for routine identification of yeasts.

Keywords:
protein extraction Candida identification scores

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