Classification of Bacillus and Brevibacillus species using rapid analysis of lipids by mass spectrometry.
Bacillus are aerobic spore-forming bacteria that are known to lead to specific diseases, such as anthrax and food poisoning. This study focuses on the characterization of these bacteria by the detection of lipids extracted from 33 well-characterized strains from the Bacillus and Brevibacillus genera, with the aim to discriminate between the different species. For the purpose of analysing the lipids extracted from these bacterial samples, two rapid physicochemical techniques were used: matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) and liquid chromatography in conjunction with mass spectrometry (LC-MS). The findings of this investigation confirmed that MALDI-TOF-MS could be used to identify different bacterial lipids and, in combination with appropriate chemometrics, allowed for the discrimination between these different bacterial species, which was supported by LC-MS. The average correct classification rates for the seven species of bacteria were 62.23 and 77.03 % based on MALDI-TOF-MS and LC-MS data, respectively. The Procrustes distance for the two datasets was 0.0699, indicating that the results from the two techniques were very similar. In addition, we also compared these bacterial lipid MALDI-TOF-MS profiles to protein profiles also collected by MALDI-TOF-MS on the same bacteria (Procrustes distance, 0.1006). The level of discrimination between lipids and proteins was equivalent, and this further indicated the potential of MALDI-TOF-MS analysis as a rapid, robust and reliable method for the classification of bacteria based on different bacterial chemical components. Graphical abstract MALDI-MS has been successfully developed for the characterization of bacteria at the subspecies level using lipids and benchmarked against HPLC.
School of Chemistry and Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
Najla
N
AlMasoud
School of Chemistry and Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
Yun
Y
Xu
School of Chemistry and Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
Drupad K
DK
Trivedi
Shimadzu, Kratos Analytical Ltd. Wharfside, Trafford Wharf Road, Manchester, M17 1GP, UK.
Simona
S
Salivo
Shimadzu, Kratos Analytical Ltd. Wharfside, Trafford Wharf Road, Manchester, M17 1GP, UK.
Tom
T
Abban
School of Chemistry and Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
Nicholas J W
NJ
Rattray
School of Chemistry and Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
Ewa
E
Szula
School of Chemistry and Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.|Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh, 11451, Saudi Arabia.
Haitham
H
AlRabiah
School of Chemistry and Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
Ali
A
Sayqal
School of Chemistry and Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK. roy.goodacre@manchester.ac.uk.
Royston
R
Goodacre
D001407:Bacillus / Q000737:chemistry / Q000145:classification* / Q000378:metabolism; D001426:Bacterial Proteins / Q000145:classification / Q000302:isolation & purification; D015373:Bacterial Typing Techniques; D058675:Brevibacillus / Q000737:chemistry / Q000145:classification* / Q000378:metabolism; D002853:Chromatography, Liquid; D066264:Datasets as Topic; D008055:Lipids / Q000145:classification / Q000302:isolation & purification*; D010802:Phylogeny; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
D001426:Bacterial Proteins; D008055:Lipids
Bacillus; Brevibacillus; Classification; Extraction; LC-MS; Lipids; MALDI-TOF-MS