Application of MALDI-TOF mass spectrometry to study gut microbiota of newborns
AbstractThe aim of the study is to conduct a comparative analysis of the effectiveness of species identification of microorganisms in studies of the gut microbiota of newborns using two different methods: MALDI-TOF-MS and sequencing of 16s rRNA gene loci.
Material and methods. The study of the gut microbiota was conducted on a group of newborns from various departments of the National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation in 2019. The study of the composition of the intestinal microbiota of newborns was carried out using an extended range of selective and non-selective nutrient media and incubation in aerobic, microaerophilic and anaerobic conditions. All isolated in the work pure cultures of microorganisms were taken for the study. Identification of microorganisms was performed using two different methods: MALDI-TOF-MS and sequencing of 16s rRNA gene loci.
Results. For the study, 84 pure cultures of microorganisms isolated from the feces of newborn children were selected. The MALDI-TOF-MS analysis was performed for each isolated isolate. For most of the isolates (82%), the values of the SCORE indicator were obtained in the range from 1.68 to 2.40, which made it possible to attribute each isolate to a particular intended species. For 15 (18%) isolates of microorganisms, correct species identification was not possible. The results of species identification of the studied microbial isolates obtained by both methods were identical for 58 of the 69 isolates (84%). In some cases, the determination of the type of microorganisms using the MALDI-TOF-MS was incorrect, and only the use of sequencing of species-specific loci of the 16s rRNA gene allowed to obtain the correct result.
Conclusion. Results obtained by sequencing species-specific loci of the 16s rRNA gene correlate well with results obtained using a time-of-flight MALDI-TOF mass spectrometer. It has been shown that MALDI-TOF-MS can be effectively used in studies of the gut microbiota of newborns.
Keywords:MALDI-TOF-MS, 16SrRNA gene sequencing, culturomics, microbiota, gut microbiota, newborns
Conflict of interests. The authors declare no conflict of interests.
For citation: Priputnevich T.V., Nikolaeva A.V., Gordeev A.B., Isaeva E.L., Muravieva V.V., Lyubasovskaya L.A., Shubina J., Trofimov D.Yu., Melkumyan A.R., Zubkov V.V. Application of MALDI-TOF mass spectrometry to study gut microbiota of newborns. Akusherstvo i ginekologiya: novosti, mneniya, obuchenie [Obstetrics and Gynecology: News, Opinions, Training]. 2020; 8 (1): 22-9. doi: 10.24411/2303-9698-2020-11003 (in Russian)
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