Advances in mass spectrometry for the identification of pathogens

Abstract

Mass spectrometry (MS) has become an important technique to identify microbial biomarkers. The rapid and accurate MS identification of microorganisms without any extensive pretreatment of samples is now possible. This review summarizes MS methods that are currently utilized in microbial analyses. Affinity methods are effective to clean, enrich, and investigate microorganisms from complex matrices. Functionalized magnetic nanoparticles might concentrate traces of target microorganisms from sample solutions. Therefore, nanoparticle-based techniques have a favorable detection limit. MS coupled with various chromatographic techniques, such as liquid chromatography and capillary electrophoresis, reduces the complexity of microbial biomarkers and yields reliable results. The direct analysis of whole pathogenic microbial cells with matrix-assisted laser desorption/ionization MS without sample separation reveals specific biomarkers for taxonomy, and has the advantages of simplicity, rapidity, and high-throughput measurements. The MS detection of polymerase chain reaction (PCR)-amplified microbial nucleic acids provides an alternative to biomarker analysis. This review will conclude with some current applications of MS in the identification of pathogens.

Capillary electrophoresis based on nucleic acid detection for diagnosing human infectious disease

“…6. CE combined with other techniques capitalizes on the advantages of the other techniques, such as CE combined with MS for the detection of PCR-amplified microbial nucleic acids [167,168]. CE is a rapid and highly efficient separation technique, while MS has a higher specificity and sensitivity.…”

Biomarker Characterization by MALDI–TOF/MS

“…Conventional diagnosis of microorganisms uses phenotypic identification and gene sequencing, which is tedious and time-consuming. In contrast, MALDI-TOF/MS is a simple, rapid, reproducible, and low-cost technique that has been successfully applied to identify pathogens [135][136][137][138][139][140][141][142][143]. Based on characteristic peptide and protein profiles obtained from intact cells, MALDI-TOF/MS allows a highly discriminatory identification of bacteria, yeasts, and filamentous fungi even after 10 min of culture.…”

“…Based on characteristic peptide and protein profiles obtained from intact cells, MALDI-TOF/MS allows a highly discriminatory identification of bacteria, yeasts, and filamentous fungi even after 10 min of culture. With the use of a database to identify microorganisms, the reliability and accuracy of this approach have been demonstrated, and systems (including instrument and software) are already commercially available [135][136][137][138][139][140][141][142][143]. The applications of MALDI-TOF/MS in research on pathogens and microorganisms include identification of pathogens from positive blood cultures and urine, real-time diagnosis of blood stream infections, and detection of antibiotic resistance bacteria [135][136][137][138][139][140][141][142][143].…”

The Changing Role of the Clinical Microbiology Laboratory in Defining Resistance in Gram-negatives

“…128 Overall, the main advantages of MALDI-TOF MS are its rapidity, very low costs, and consistency. [129][130][131][132] Recently, this system has also been applied to (i) recognize antibiotic degradation owing to resistance proteins [133][134][135][136][137][138][139][140][141][142] ; (ii) discover mutations within resistance genes through DNA minisequencing 142 ; and (iii) study clonality of Gram-negative pathogens (eg, detection of ST131 or ST405 E coli). 143,144 Numerous studies have assessed specifically the usefulness of MALDI-TOF MS for the identification of b-lactam degradation products in the presence of hydrolyzing b-lactamases, [137][138][139][140][141]145,146 including directly from positive blood cultures.…”