Chuan-Sheng Lin1, Chih-Cheng Su1, Shang-Chen Hsieh1, Chia-Chen Lu2, Tsu-Lan Wu3, Ju-Hsin Jia4, Ting-Shu Wu5, Chau-Chung Han6, Wen-Cherng Tsai7, Jang-Jih Lu8, Hsin-Chih Lai9. 1. Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang-Gung University, Gueishan, Taoyuan, Taiwan. 2. Department of Respiratory Therapy, Fu-Jen Catholic University, New Taipei, Taiwan. 3. Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang-Gung University, Gueishan, Taoyuan, Taiwan; Department of Clinical Pathology, Chang-Gung Memorial Hospital, Taoyuan, Taiwan; Department of Laboratory Medicine, Chang-Gung Memorial Hospital, Taoyuan, Taiwan. 4. Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang-Gung University, Gueishan, Taoyuan, Taiwan; Department of Laboratory Medicine, Chang-Gung Memorial Hospital, Taoyuan, Taiwan. 5. Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan. 6. Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan. 7. Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan. 8. Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang-Gung University, Gueishan, Taoyuan, Taiwan; Department of Laboratory Medicine, Chang-Gung Memorial Hospital, Taoyuan, Taiwan. Electronic address: janglu45@gmail.com. 9. Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang-Gung University, Gueishan, Taoyuan, Taiwan. Electronic address: hclai@mail.cgu.edu.tw.
Abstract
BACKGROUND: Rapid and accurate discrimination of Mycobacterium avium from other mycobacteria is essential for appropriate therapeutic management and timely intervention for infection control. However, routine clinical identification methods for M. avium are both time consuming and labor intensive. In the present study, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to identify specific cellular protein pattern for rapid identification of M. avium isolates. METHODS: A total of 40 clinically relevant Mycobacterium strains comprising 13 distinct species were enrolled for the MALDI-TOF MS identification. A 10-minute extraction-free examination procedure was set up to obtain mass spectral fingerprints from whole bacterial cells. RESULTS: The characteristic mass spectral peak patterns in the m/z (mass/charge ratio) range of 5-20 kDa can be obtained within 10 minutes. The species-specific mass spectra for M. avium is identified and can be differentiated from as Mycobacterium strains. This technique shortens and simplifies the identification procedure of MALDI-TOF MS and may further extend the mycobacterial MALDI-TOF MS database. CONCLUSION: Simplicity and rapidity of identification procedures make MALDI-TOF MS an attractive platform in routine identification of mycobacteria. MALDI-TOF MS is applicable for rapid discrimination of M. avium from other Mycobacterium species, and shows its potential for clinical application.
BACKGROUND: Rapid and accurate discrimination of Mycobacterium avium from other mycobacteria is essential for appropriate therapeutic management and timely intervention for infection control. However, routine clinical identification methods for M. avium are both time consuming and labor intensive. In the present study, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to identify specific cellular protein pattern for rapid identification of M. avium isolates. METHODS: A total of 40 clinically relevant Mycobacterium strains comprising 13 distinct species were enrolled for the MALDI-TOF MS identification. A 10-minute extraction-free examination procedure was set up to obtain mass spectral fingerprints from whole bacterial cells. RESULTS: The characteristic mass spectral peak patterns in the m/z (mass/charge ratio) range of 5-20 kDa can be obtained within 10 minutes. The species-specific mass spectra for M. avium is identified and can be differentiated from as Mycobacterium strains. This technique shortens and simplifies the identification procedure of MALDI-TOF MS and may further extend the mycobacterial MALDI-TOF MS database. CONCLUSION: Simplicity and rapidity of identification procedures make MALDI-TOF MS an attractive platform in routine identification of mycobacteria. MALDI-TOF MS is applicable for rapid discrimination of M. avium from other Mycobacterium species, and shows its potential for clinical application.