摘要
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been used for many years to rapidly identify whole bacteria. However, no consistent methodology exists for the rapid identification of bacteria cultured in liquid media. Thus, in this study we explored the use of MALDI-TOF MS analysis for rapid identification of cells cultured in liquid media. We determined that 2,5-dihydroxybenzoic acid (50 mg mL-1, 50% acetonitrile, 0.1% trifluoroacetic acid) was the best matrix solution for MALDI-TOF MS for this type of study. Moreover, the tested strains were successfully differentiated by principal component analysis, and the main characteristics of the mass peaks for each species were found in mixed culture samples. In addition, we found that the minimum number of cells for detection was 1.8×103. In conclusion, our findings suggest that MS-based techniques can be developed as an auxiliary method for rapidly and accurately identifying bacteria cultured in liquid media.
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF MS） has been used for many years to rapidly identify whole bacteria. However, no consistent methodology exists for the rapid identification of bacteria cultured in liquid media. Thus, in this study we explored the use of MALDI-TOF MS analysis for rapid identification of cells cultured in liquid media. We determined that 2,5-dihydroxybenzoic acid （50 mg mL-1, 50% acetonitrile, 0.1% trifluoroacetic acid） was the best matrix solution for MALDI-TOF MS for this type of study. Moreover, the tested strains were successfully differentiated by principal component analysis, and the main characteristics of the mass peaks for each species were found in mixed culture samples. In addition, we found that the minimum number of cells for detection was 1.8×103. In conclusion, our findings suggest that MS-based techniques can be developed as an auxiliary method for rapidly and accurately identifying bacteria cultured in liquid media.
基金
supported by the National Science and Technology Major Project (Grant No. 2008ZX10207)
the Innovation Method Fund of Ministry of Science and Technology of China (Grant Nos. 2008IM022000 and 2009IM030300)
the National Science and Technology Support Program (Grant No. 2008BAK41B0)
