Mechanisms of Polyethylene Terephthalate Pellet Fragmentation into Nanoplastics and Assimilable Carbons by Wastewater .

bacteria are enriched on poly(ethylene terephthalate) (PET) microplastics in wastewaters and urban rivers, but the PET-degrading mechanisms remain unclear. Here, we investigated these mechanisms with KF-1, a wastewater isolate, by combining microscopy, spectroscopy, proteomics, protein modeling, and genetic engineering. Compared to minor dents on PET films, scanning electron microscopy revealed significant fragmentation of PET pellets, resulting in a 3.

Complex regulation in a Comamonas platform for diverse aromatic carbon metabolism.

Critical to a sustainable energy future are microbial platforms that can process aromatic carbons from the largely untapped reservoir of lignin and plastic feedstocks. Comamonas species present promising bacterial candidates for such platforms because they can use a range of natural and xenobiotic aromatic compounds and often possess innate genetic constraints that avoid competition with sugars. However, the metabolic reactions of these species are underexplored, and the regulatory mechanisms are unknown.

Analogous Metabolic Decoupling in Pseudomonas putida and Comamonas testosteroni Implies Energetic Bypass to Facilitate Gluconeogenic Growth.

Gluconeogenic carbon metabolism is not well understood, especially within the context of flux partitioning between energy generation and biomass production, despite the importance of gluconeogenic carbon substrates in natural and engineered carbon processing. Here, using multiple omics approaches, we elucidate the metabolic mechanisms that facilitate gluconeogenic fast-growth phenotypes in Pseudomonas putida and Comamonas testosteroni, two species with distinct metabolic networks. In contrast to the genetic constraint of , which lacks the enzymes required for both sugar uptake and a complete oxidative pentose phosphate (PP) pathway, sugar metabolism in P.

Effects of Phosphonate Herbicides on the Secretions of Plant-Beneficial Compounds by Two Plant Growth-Promoting Soil Bacteria: A Metabolomics Investigation.

Plant growth-promoting rhizobacteria (PGPR) that colonize plant roots produce a variety of plant-beneficial compounds, including plant-growth regulators, metal-scavenging compounds, and antibiotics against plant pathogens. Adverse effects of phosphonate herbicides, the most extensively used herbicides, on the growth and metabolism of PGPR species have been widely reported. However, the potential consequence of these effects on the biosynthesis and secretion of PGPR-derived beneficial compounds still remains to be investigated.

Syntrophic splitting of central carbon metabolism in host cells bearing functionally different symbiotic bacteria.

Insects feeding on the nutrient-poor diet of xylem plant sap generally bear two microbial symbionts that are localized to different organs (bacteriomes) and provide complementary sets of essential amino acids (EAAs). Here, we investigate the metabolic basis for the apparent paradox that xylem-feeding insects are under intense selection for metabolic efficiency but incur the cost of maintaining two symbionts for functions mediated by one symbiont in other associations. Using stable isotope analysis of central carbon metabolism and metabolic modeling, we provide evidence that the bacteriomes of the spittlebug Clastoptera proteus display high rates of aerobic glycolysis, with syntrophic splitting of glucose oxidation.

Advancements in C isotope tracking of synergistic substrate co-utilization in Pseudomonas species and implications for biotechnology applications.

Pseudomonads are well-known to thrive in diverse and complex nutritional habitats, and these capabilities make Pseudomonas species attractive as whole-cell biocatalysts. Industrial bioconversion processes often rely on complex uptake and synergistic metabolic systems due to the presence of varied carbon substrates in nutrient feedstocks. Isotope labeling experiments (ILEs) are emerging techniques used to elucidate cell metabolism following feeding on isotopically enriched substrates and are pivotal to the understanding of carbon partitioning during co-utilization.

The Metabolome of Associations between Xylem-Feeding Insects and their Bacterial Symbionts.

Metabolomics has increasingly led to important insights in chemical ecology by identifying environmentally relevant small molecules that mediate inter-organismal interactions. Nevertheless, the application of metabolomics to investigate interactions between phytophagous insects and their microbial symbionts remains underutilized. Here, we investigated the metabolomes of the bacteriomes (organs bearing symbiotic bacteria) isolated from natural populations of five species of xylem-feeding insects.

Multi-omics analysis unravels a segregated metabolic flux network that tunes co-utilization of sugar and aromatic carbons in .

species thrive in different nutritional environments and can catabolize divergent carbon substrates. These capabilities have important implications for the role of these species in natural and engineered carbon processing. However, the metabolic phenotypes enabling to utilize mixed substrates remain poorly understood.

A Cyclic Metabolic Network in Pseudomonas protegens Pf-5 Prioritizes the Entner-Doudoroff Pathway and Exhibits Substrate Hierarchy during Carbohydrate Co-Utilization.

The genetic characterization of Pf-5 was recently completed. However, the inferred metabolic network structure has not yet been evaluated experimentally. Here, we employed C-tracers and quantitative flux analysis to investigate the intracellular network for carbohydrate metabolism.

Quantitation of carbohydrate monomers and dimers by liquid chromatography coupled with high-resolution mass spectrometry.

As remnants of plant wastes or plant secretions, carbohydrates are widely found in various environmental matrices. Carbohydrate-containing feedstocks represent important carbon sources for engineered bioproduction of commodity compounds. Routine monitoring and quantitation of heterogenous carbohydrate mixtures requires fast, accurate, and precise analytical methods.