Drancourtella massiliensis gen. nov., sp. nov. isolated from fresh healthy human faecal sample from South France

Gut microbiota compositions in the carriers and noncarriers of third-generation cephalosporin-resistant Escherichia coli: A study among children in southern Taiwan

BACKGROUND

Antimicrobial resistance, particularly in third-generation cephalosporin-resistant (3GC-R) Escherichia coli (E. coli), poses major global health challenges and has various clinical implications. Researchers have explored the relationship between extended-spectrum β-lactamase-producing E. coli and gut microbiota composition, which influence host health and disease susceptibility, in adults. In this study, we analyzed gut microbiota composition in Taiwanese children by the colonization status of 3GC-R E. coli.

METHODS

This cross-sectional study included children (age, 0-6 years) from Kaohsiung, Taiwan. Fecal samples were subjected to microbiological and gut microbiome (full-length 16S rRNA sequencing) analyses. The antimicrobial susceptibility of E. coli colonies isolated from the samples was tested. Furthermore, gut microbiota compositions and diversity indices were compared between 3GC-R E. coli carriers and noncarriers.

RESULTS

Approximately 46% of all children aged <6 years carried 3GC-R E. coli. The abundances of Drancourtella, Romboutsia, and Desulfovibrio (genus level) were higher in carriers than in noncarriers. By contrast, the abundances of Odoribacteraceae (family level) and Sutterella (genus level) were higher in noncarriers than in carriers. No significant between-group difference was observed in alpha diversity. However, a significant between-group difference was noted in beta diversity (unweighted UniFrac analysis).

CONCLUSION

This is the first study that investigated differences in the gut microbiota between healthy 3GC-R E. coli carriers and noncarriers in children, suggesting potential mechanisms involving altered utilization of short-chain fatty acids and elevated succinate levels contributing to increased colonization of 3GC-R E. coli. The other taxa identified in this study may contribute to colonization resistance in the pediatric population.

Alterations in intestinal microbiota in ultramarathon runners

To date, only one study has reported changes in the gut microbiome of an ultramarathon runner before and after competing in the race. Herein we aimed to investigate changes in intestinal microbiota in nine ultramarathon runners. Eight of the nine participants ran 96.102 km (up 8062 m, down 6983 km) and one ran 99.12 km (up 8448 m, down 7369 m) within 38–44 h. Intestinal microbiota alterations were examined at three timepoints: before (Pre), after (Post), and 10 days after (Recovery) the race. The α- and β-diversity of intestinal microbiota were unaffected by the race. Six of the nine participants showed the B-type enterotype, while the remaining three showed the P-type enterotype; however, significant difference between enterotypes was not observed in the influence of the ultramarathon on intestinal microbiota. The abundance of mean Faecalibacterium prausnitzii, was significantly decreased from 2.9% (Pre) to 1.6% (Post), as well as other three butyrate producing bacteria. One participant with the largest decrease in F. prausnitzii abundance (− 85.7%) reported sluggishness and shallow sleep from Post to Recovery. Our findings revealed that the abundance of butyrate-producing bacteria is decreased in ultramarathon runners, which consequently decreases butyrate levels in the intestine and affects host immune function.

Dietary Supplementation of Shredded, Steam-Exploded Pine Particles Decreases Pathogenic Microbes in the Cecum of Acute Heat-Stressed Broilers

The gut microbiome stimulates nutrient metabolism and could effectively generate heat tolerance in chickens. This study investigates the effects of dietary steam-exploded pine particle (SPP) supplementation and subsequent acute heat stress on productive performance and cecum microbiome in broilers. Eight-day Ross 308 broilers were distributed in three groups with 0%, 1%, and 2% SPP in diets. On the 41st day, forty birds were allocated to four groups with ten birds each. The treatments were control diet at thermoneutral temperature (0% NT) and acute heat-stressed (HS) birds fed control (0% HS), 1% (1% HS), and 2% (2% HS) SPP. Parameters recorded were body weight (BW), feed intake (FI), rectal temperature (RT), relative organ weight, and metagenome analysis from cecum samples. Percent difference in BW, FI, and RT was decreased in HS birds. Metagenome analysis revealed similar richness and diversity in microbial communities. The relative abundance of the bacterial genus such as Limosilactobacillus, Drancourtella, and Ihubacter was increased while that of Alistipes, Alkalibacter, Lachnotalea, and Turicibacter was decreased in SPP supplemented HS birds. Concludingly, the production performance of broilers is negatively influenced during HS, and 2% dietary SPP supplementation may reduce the adverse effects of HS by modifying the microbiota in chickens.

Methods for culturing anaerobes from human specimen

Anaerobes represent the dominating population in the human gut microbiota and play a key role in gut homeostasis. In addition, several anaerobes are now considered as probiotics and they remain essential to several processes in the field of biotechnology. With the implementation of MALDI-TOF MS in routine laboratories, anaerobes are no longer neglected in clinical microbiology, as their identification is made easy. However, the isolation and identification of anaerobic bacteria, remains time consuming, fastidious and costly. Various strategies have been developed, from sampling to culturing human specimens, which will be discussed in this paper. Also, particular attention is paid to isolating species with special medical importance, as for contribution to the field of culturomics.