Biology subjects

Jantscher-Krenn, E.

Publications and source records attributed to Jantscher-Krenn, E..

4 recordsLinked to original sources

bioRxiv2024

First-Year Dynamics of the Anaerobic Microbiome and Archaeome in Infants Oral and Gastrointestinal Systems

Recent research provides new insights into the early establishment of the infant gut microbiome, emphasizing the influence of breastfeeding on the development of gastrointestinal (GIT) microbiomes. In our study, we longitudinally examined the taxonomic and functional dynamics of the oral and GIT microbiomes of healthy infants (n=30) in their first year, focusing on the often over-looked aspects, the development of archaeal and anaerobic microbiomes. Breastfed (BF) infants exhibit a more defined transitional phase in their oral microbiome compared to non-breastfed (NBF) infants, marked by a decrease in Streptococcus and the emergence of anaerobic genera such as Granulicatella. This phase, characterized by increased alpha diversity and significant changes in beta diversity, occurs earlier in NBF infants (months 1-3) than in BF infants (months 4-6), suggesting that breastfeeding supports later, more defined microbiome maturation. We demonstrated the presence of archaea in the infant oral cavity and GIT microbiome from early infancy, with Methanobrevibacter being the predominant genus. Still, transient patterns show that no stable archaeome is formed. The GIT microbiome exhibited gradual development, with BF infants showing increased diversity and complexity between months 3 and 8, marked by anaerobic microbial networks. NBF infants displayed complex microbial co-occurrence patterns from the start. Those strong differences between BF and NBF infants GIT microbiomes are less pronounced on functional levels than on taxonomic level. Overall, the infant microbiome differentiates and stabilizes over the first year, with breastfeeding playing a crucial role in shaping anaerobic microbial networks and overall microbiome maturation.

microbiology↗

bioRxiv2023

The Dynamics of the Female Microbiome: Unveiling Abrupt Changes of Microbial Domains across Body Sites from Preconception to Perinatal Phase

The microbial ecosystem of women undergoes enormous changes during pregnancy and the perinatal period. Little is known about the extent of changes in the maternal microbiome beyond the vaginal cavity and its recovery after birth. In this study, we followed pregnant women (mpre, n = 30) into the postpartum period (1 month postpartum, mpost, n = 30). We profiled their oral, urinary, and vaginal microbiome, archaeome, mycobiome and urinary metabolome and compared them with nonpregnant women (np, n = 29). Overall, pregnancy status (np, mpre, mpost) had a smaller effect on the microbiomes than body site, but massive transitions were observed for the oral and urogenital (vaginal and urinary) microbiomes. While the oral microbiome fluctuates during pregnancy but stabilizes rapidly within the first month postpartum, the urogenital microbiome is characterized by a major remodeling caused by a massive loss of Lactobacillus and thus a shift from vaginal community state type (CST) I (40% of women) to CST IV (85% of women). The urinary metabolome rapidly reached an np-like composition after delivery, apart from lactose and oxaloacetic acid, which were elevated during active lactation. Fungal and archaeal profiles were indicative of pregnancy status. Methanobacterium signatures were found exclusively in np women, and Methanobrevibacter showed opposite behavior in oral cavity (increased) and vagina (decreased) during pregnancy. Our findings suggest that the massive remodeling of the maternal microbiome and metabolome needs more attention and that potential interventions could be envisioned to optimize recovery and avoid long-term effects on maternal health and subsequent pregnancies.

microbiology↗

bioRxiv2023

Longitudinal Variability of Bifidobacterium Species in the Infant Gut is Independent of Maternal Milk HMO Composition

The development of the infant gut microbiome is primarily influenced by the infant feeding type, with breast milk serving as the optimal source of nutrition. Breast milk contains human milk oligosaccharides (HMOs) that act as nourishment for the developing gut microbiome, potentially conferring advantages to specific bacterial species. Previous studies have demonstrated the ability of certain Bifidobacterium species to utilize individual HMOs, however a longitudinal study examining the evolving microbial community at a high resolution in the context of mothers milk HMO composition is lacking. Here, we explored the relationship between the HMO composition in mothers milk and the abundance of Bifidobacterium species in the infant gut throughout the course of early life. To enable subspecies taxonomic classification, we developed a high-throughput method for quantifying the abundance of Bifidobacterium longum subsp. infantis (BL. infantis; the best known HMO-utilizer) from metagenomic sequencing. We applied this method to a longitudinal cohort consisting of 21 mother-infant dyads, from whom we collected matched breast milk and infant stool samples at multiple time points during the first year of life. We observed substantial changes in the infant gut microbiome over the course of several months, while the HMO composition in mothers milk remained relatively stable. Bifidobacterium species were a prominent factor contributing to the variation observed among samples; however, no significant associations were found between specific HMOs in mothers milk and the abundance of Bifidobacterium species. Finally, the longitudinal nature of our cohort enabled us to characterize the dynamic colonization of BL. infantis in the infant gut, which surprisingly began late in the breastfeeding period. Applying our BL. infantis quantification method to additional datasets from various geographical locations, we found similar, late-colonization by BL. infantis, highlighting the importance of quantifying BL. infantis in the infant gut.

microbiology↗

bioRxiv2019

Human Milk Oligosaccharides modulate the risk for preterm birth in a microbiome dependent and independent manner

BackgroundPreterm birth is one of the leading causes of neonatal mortality. The causes for spontaneous preterm birth (PTB) are multifactorial and remain often unknown. In this study, we tested the hypothesis that human milk oligosaccharides (HMOs) in blood and urine modulate the maternal urinary and vaginal microbiome and influence the risk for PTB. We analyzed the vaginal and urinary microbiome of a cross-sectional cohort of women with and without preterm labor and correlated our findings with measurements of metabolites and HMOs in urine and blood.\n\nResultsWe identified several microbial signatures associated with short cervix, PTB and/or preterm contractions such as Lactobacillus jensenii, L. gasseri, Ureaplasma sp. and Gardnerella sp.. Additionally, we observed associations between sialylated HMOs, in particular 3-sialyllactose, with PTB, short cervix and increased inflammation and confirmed an influence of HMOs on the microbiome profile.\n\nConclusionsIdentifying serum and urinary HMOs and several key microorganisms associated with PTB, our findings point at two distinct processes modulating the risk for PTB. One process seems to be driven by sterile inflammation, characterized by increased concentrations of sialylated HMOs in serum. Another process might be microbiome-mediated, potentially driven by secretor-active HMOs in urine. Our results support current efforts to improve diagnostics and therapeutic strategies.

microbiology↗