Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Synbiotics”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

3 recordsLinked to original sources
PubMed1976

Control of synbiotic nitrogen fixation in Rhizobia. Regulation of NH4+ assimilation.

This communication is concerned with physiological, biochemical, and genetic studies of the regulation of ammonium (NH4+) assimilation by Rhizobia (root nodule bacteria) that infect leguminous plants. The major conclutions are (i) physiological studies show that Rhizobia are able to assimilate NH4+ for growth only when supplemented with certain organic nitrogen sources (e.g., L-aspartate, L-leucine, L-serine). Addition of as little as 2 mug/ml of L-aspartate supported growth on NH4+ as nitrogen source. In contrast, addition of glutamate in combination with NH4+-blocked NH4+ utilization; (ii) biochemical analysis show that glutamate synthase activity (NADP- and NAD-linked) is always present in cells capable of assimilating NH4+; also cells without glutamate synthase activity were found to be incapable of NH4+ utilization. Glutamate synthase levels were observed to fluctuate markedly depending on the available nitrogen source and on the growth stage of the culture; (iii) mutants were selected in which assimilation of NH4+ is no longer subject to inhibition (repression?) by glutamate. The levels of glutamate synthase activity (NADP-linked) (in the presence of glutamate) show approximately a two-fold increase over the level in the parent strain. The mutants no longer require supplementation with small amounts of organic nitrogen for growth in medium containing inorganic nitrogen (e.g., NH4+ or NO3-); (iv) these findings are discussed in relation to the working model of symbiotic nitrogen fixation recently proposed (O'Gara and Shanmugam (1976), Biochim. Biophys. Acta 437, 313--321).

Aspartic Acid↗
PubMed2026

Metabolome-driven rhizosphere microbiome assembly determining the health of medicinal herb (Angelica sinensis) against root rot.

BACKGROUND: The rhizosphere-associated microbiota plays a crucial role in plant responses to disease stress. Plant secondary metabolites are recognized as crucial mediators in the assembly of rhizosphere microbial communities, particularly by enhancing the colonization of beneficial microorganisms. Despite this recognized importance, a deeper understanding of how such metabolome-driven microbiome assembly specifically determines plant resistance against soil-borne diseases is still lacking. RESULTS: Here, we focused on the widely planted medicinal plant Angelica sinensis and demonstrated that root rot-diseased rhizosphere soils (DRS) exhibited a higher relative abundance of Fusarium and a lower relative abundance of Streptomyces compared to healthy rhizosphere soils (HRS). Shotgun metagenomic sequencing revealed that metabolism-associated genes, particularly those related to steroid degradation, are significantly enriched in HRS samples. Subsequent genome and functional gene analysis of Streptomyces revealed that the steroid degradation-related genes are associated with rhizosphere colonization in hosts. Rhizosphere Streptomyces S15 directly antagonized Fusarium and enhanced the root resistance of A. sinensis. Comparative metabolomics showed that A. sinensis plants from HRS secreted more lipid and lipid-like molecules than those from DRS, especially sterol lipids and long-chain fatty acids, which promoted the growth of Streptomyces S15 isolates. Transcriptome analysis validated that the lipid hormones are essential for sporulation, biofilm formation, and streptomycin biosynthesis of S15 strain. Finally, exogenous application of synbiotics (lipid prebiotics and S15) to A. sinensis resulted in the enrichment of S15-homologous Streptomyces amplicon sequence variant (ASV), further establishing beneficial bacterial communities in Fusarium-stressed rhizospheres. CONCLUSIONS: Our study proposes that A. sinensis recruits steroid-metabolizing Streptomyces species by exuding key lipid compounds (i.e., methyl jasmonate and brassinolide) to combat Fusarium root rot. This study provides novel insights into using functional synbiotics as a promising strategy for manipulating plant-microbiome interactions to promote sustainable agriculture. Video Abstract.

Rhizosphere↗
PubMed2026

From dysbiosis to resilience: Microbiome engineering for sustainable shrimp aquaculture.

The intensification of shrimp aquaculture has increased exposure to disease, environmental perturbations, and antimicrobial pressure, making microbial stability increasingly relevant to sustainable production. Microbiome stability-encompassing resistance to disturbance and resilience of functional recovery-provides an ecological framework for understanding how shrimp and culture-environment microbial communities respond to intensive farming. This review examines the transition from microbial homeostasis to dysbiosis and evaluates how microbiome engineering could redirect disrupted communities towards resilient states. Evidence is integrated across the intestine, hepatopancreas, rearing water, sediment and biofloc to assess how host genetics, ontogeny, diet, culture conditions, antibiotics and pollutants shape microbiome assembly and destabilization. Disease-associated changes in acute hepatopancreatic necrosis disease, white faeces syndrome, Enterocytozoon hepatopenaei infection, and white spot syndrome virus infection are critically evaluated, with explicit separation of associations, pathogen-induced dysbiosis, and community-level causality. Established and emerging interventions-including probiotics, prebiotics, synbiotics, functional diets, biofloc management, phages, postbiotics, microbiota transplantation and synthetic microbial communities-are assessed according to their capacity to modify microbial function, persistence and recovery rather than taxonomic change alone. We further examine how multi-omics, microbiome-informed breeding, and environmental monitoring could support biomarker development, predictive decision support and context-specific intervention. We argue that progress requires a shift from taxonomic description to function-guided engineering, from endpoint comparisons to direct measurement of resilience, and from laboratory efficacy to reproducible farm-scale validation. Overall, microbiome management may contribute to more disease-resilient and sustainable shrimp production, provided that its effectiveness can be validated under commercial farming conditions.

Dysbiosis↗