Istituto di Microbiologia, Università Cattolica del Sacro Cuore, Rome, Italy.
Clin Microbiol Infect. 2011 Jan;17(1):44-9. doi: 10.1111/j.1469-0691.2010.03181.x.
As a result of variable expression of biochemical characters, misidentification by conventional phenotypic means often occurs with clinical isolates belonging to Staphylococcus species. Therefore, we evaluated the use of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of 450 blood isolates of the most relevant staphylococcal species, using sequence analysis of the rpoB gene as the reference method. A correct species identification by MALDI-TOF was obtained in 99.3% (447/450), with only three isolates being misidentified. In addition, MALDI-TOF correctly identified all the staphylococcal subspecies studied, including Staphylococcus capitis subsp. capitis and subsp. urealyticus, Staphylococcus cohnii subsp. urealyticus, Staphylococcus hominis subsp. novobiosepticus and subsp. hominis, Staphylococcus saprophyticus subsp. saprophyticus, Staphylococcus schleiferi subsp. schleiferi and Staphylococcus sciuri subsp. sciuri. Thus, MALDI-TOF MS-based species identification of staphylococci can be routinely achieved without any substantial costs for consumables or the time needed for labour-intensive DNA sequence analysis.
由于生化特征的表达存在差异,临床分离的葡萄球菌属菌株常常通过常规表型方法被错误鉴定。因此,我们评估了基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)用于鉴定 450 株血液分离的最相关葡萄球菌属菌株的用途,以 rpoB 基因序列分析作为参考方法。MALDI-TOF 对 99.3%(447/450)的菌株进行了正确的种属鉴定,只有 3 株被错误鉴定。此外,MALDI-TOF 还正确鉴定了所有研究的葡萄球菌亚种,包括头状葡萄球菌亚种、解脲亚种,科氏葡萄球菌亚种、解脲亚种,人葡萄球菌亚种、新生物亚种和人亚种,腐生葡萄球菌亚种、腐生亚种,施氏葡萄球菌亚种、施氏亚种。因此,MALDI-TOF MS 可常规用于葡萄球菌的种属鉴定,无需耗费大量耗材,也无需进行耗时的劳动密集型 DNA 序列分析。