The effect of plastic additives on growth and function.

Plastic waste has the potential for significant consequences on various ecosystems; yet, there are gaps in our understanding of the interaction of bacteria with polymer additives. We studied the impact of representative additive molecules to the viability and cell function of Shewanella oneidensis MR-1. Specifically, we explored the toxicity of three bisphenols (bisphenol A (BPA), bisphenol S (BPS), and tetrabromo bisphenol A (TBBPA)) and two diesters (dibutyl sebacate (DBS) and diisobutyl phthalate (DIBP)) in order to evaluate the generalizability of toxicity based on similar molecular structures.

Asgard archaea capable of anaerobic hydrocarbon cycling.

Large reservoirs of natural gas in the oceanic subsurface sustain complex communities of anaerobic microbes, including archaeal lineages with potential to mediate oxidation of hydrocarbons such as methane and butane. Here we describe a previously unknown archaeal phylum, Helarchaeota, belonging to the Asgard superphylum and with the potential for hydrocarbon oxidation. We reconstruct Helarchaeota genomes from metagenomic data derived from hydrothermal deep-sea sediments in the hydrocarbon-rich Guaymas Basin.

Syntrophus aciditrophicus uses the same enzymes in a reversible manner to degrade and synthesize aromatic and alicyclic acids.

Syntrophy is essential for the efficient conversion of organic carbon to methane in natural and constructed environments, but little is known about the enzymes involved in syntrophic carbon and electron flow. Syntrophus aciditrophicus strain SB syntrophically degrades benzoate and cyclohexane-1-carboxylate and catalyses the novel synthesis of benzoate and cyclohexane-1-carboxylate from crotonate. We used proteomic, biochemical and metabolomic approaches to determine what enzymes are used for fatty, aromatic and alicyclic acid degradation versus for benzoate and cyclohexane-1-carboxylate synthesis.

Complete Genome Sequence of Strain G11, a Model Sulfate-Reducing, Hydrogenotrophic, and Syntrophic Partner Organism.

Here, we report the draft genome of the Gram-negative, sulfate-reducing bacterium strain G11. Isolated from a rumen fluid enrichment, this culture has been a model syntrophic partner due to its metabolic flexibility. The assembly yielded a single circular chromosome of 3,414,943 bp and a 57% G+C content.

Membrane Complexes of Involved in Syntrophic Butyrate Degradation and Hydrogen Formation.

Syntrophic butyrate metabolism involves the thermodynamically unfavorable production of hydrogen and/or formate from the high potential electron donor, butyryl-CoA. Such redox reactions can occur only with energy input by a process called reverse electron transfer. Previous studies have demonstrated that hydrogen production from butyrate requires the presence of a proton gradient, but the biochemical machinery involved has not been clearly elucidated.

Pyrophosphate-Dependent ATP Formation from Acetyl Coenzyme A in Syntrophus aciditrophicus, a New Twist on ATP Formation.

Unlabelled: Syntrophus aciditrophicus is a model syntrophic bacterium that degrades key intermediates in anaerobic decomposition, such as benzoate, cyclohexane-1-carboxylate, and certain fatty acids, to acetate when grown with hydrogen-/formate-consuming microorganisms. ATP formation coupled to acetate production is the main source for energy conservation by S. aciditrophicus However, the absence of homologs for phosphate acetyltransferase and acetate kinase in the genome of S.

Complete genome sequence of Methanospirillum hungatei type strain JF1.

Methanospirillum hungatei strain JF1 (DSM 864) is a methane-producing archaeon and is the type species of the genus Methanospirillum, which belongs to the family Methanospirillaceae within the order Methanomicrobiales. Its genome was selected for sequencing due to its ability to utilize hydrogen and carbon dioxide and/or formate as a sole source of energy. Ecologically, M.

Proteomic analysis reveals metabolic and regulatory systems involved in the syntrophic and axenic lifestyle of Syntrophomonas wolfei.

Microbial syntrophy is a vital metabolic interaction necessary for the complete oxidation of organic biomass to methane in all-anaerobic ecosystems. However, this process is thermodynamically constrained and represents an ecosystem-level metabolic bottleneck. To gain insight into the physiology of this process, a shotgun proteomics approach was used to quantify the protein landscape of the model syntrophic metabolizer, Syntrophomonas wolfei, grown axenically and syntrophically with Methanospirillum hungatei.

The importance of hydrogen and formate transfer for syntrophic fatty, aromatic and alicyclic metabolism.

We used a combination of genomic, transcriptional and enzymatic analyses to determine the mechanism of interspecies electron transfer by two model syntrophic microorganisms, Syntrophomonas wolfei and Syntrophus aciditrophicus. Both organisms contain multiple hydrogenase and formate dehydrogenase genes, but lack genes for outer membrane cytochromes and nanowire formation. Syntrophically grown cells and cell-free extracts of S.

Identification and characterization of the first cholesterol-dependent cytolysins from Gram-negative bacteria.

The cholesterol-dependent cytolysins (CDCs) are pore-forming toxins that have been exclusively associated with a wide variety of bacterial pathogens and opportunistic pathogens from the Firmicutes and Actinobacteria, which exhibit a Gram-positive type of cell structure. We have characterized the first CDCs from Gram-negative bacterial species, which include Desulfobulbus propionicus type species Widdel 1981 (DSM 2032) (desulfolysin [DLY]) and Enterobacter lignolyticus (formerly Enterobacter cloacae) SCF1 (enterolysin [ELY]). The DLY and ELY primary structures show that they maintain the signature motifs of the CDCs but lack an obvious secretion signal.

Genomic insights into syntrophy: the paradigm for anaerobic metabolic cooperation.

Syntrophy is a tightly coupled mutualistic interaction between hydrogen-/formate-producing and hydrogen-/formate-using microorganisms that occurs throughout the microbial world. Syntrophy is essential for global carbon cycling, waste decomposition, and biofuel production. Reverse electron transfer, e.

The genome of Syntrophomonas wolfei: new insights into syntrophic metabolism and biohydrogen production.

Syntrophomonas wolfei is a specialist, evolutionarily adapted for syntrophic growth with methanogens and other hydrogen- and/or formate-using microorganisms. This slow-growing anaerobe has three putative ribosome RNA operons, each of which has 16S rRNA and 23S rRNA genes of different length and multiple 5S rRNA genes. The genome also contains 10 RNA-directed, DNA polymerase genes.

Syntrophy in anaerobic global carbon cycles.

Syntrophy is an essential intermediary step in the anaerobic conversion of organic matter to methane where metabolically distinct microorganisms are tightly linked by the need to maintain the exchanged metabolites at very low concentrations. Anaerobic syntrophy is thermodynamically constrained, and is probably a prime reason why it is difficult to culture microbes as these approaches disrupt consortia. Reconstruction of artificial syntrophic consortia has allowed uncultured syntrophic metabolizers and methanogens to be optimally grown and studied biochemically.