Project description:Several environmental bacteria encode plastic-degrading enzymes, a potential evolutionary response to the rapid introduction of plastic across global ecosystems. Given the widespread use of plastic in healthcare, we hypothesised that clinical bacterial isolates may also degrade plastic, rendering plastic-containing medical devices susceptible to degradation and failure and potentially offering these pathogens a carbon source that could be used to persist in the hospital-built environment. Here, we mined the genomes of prevalent pathogens and identified several enzymes in different pathogens with homology to known plastic-degrading enzymes. Synthesising and expressing a potential plastic-degrading enzyme derived from a Pseudomonas aeruginosa wound isolate in a heterologous host, we were able to demonstrate potent plastic degrading activity. We subsequently found that the original P. aeruginosa clinical isolate could reduce the weight of a medically relevant plastic, polycaprolactone (PCL), by 78% in 7 days, and critically could use it as a sole carbon source to grow. We uncovered a direct link to virulence, demonstrating that encoding a plastic degrading enzyme can significantly enhance biofilm formation and pathogenicity in vivo. We also demonstrate that this augmented biofilm phenotype is conserved in another P. aeruginosa PCL-degrading clinical isolate we identified in a screening. We reveal that the mechanism underpinning this enhanced biofilm formation is the incorporation of the plastic breakdown products into the extracellular matrix, leading to enhanced biofilm levels. The level of PCL degradation we show by a clinical isolate and its ability to promote a key virulence and persistence determinant such as biofilm formation indicates that the integrity of any PCL containing medical device, such as sutures or implants, and the condition of patients receiving such devices could be severely compromised by pathogens with this capacity. Given the central role of plastic in healthcare, this should be considered in the future of medical interventions and practice and hospital designs implementing this material

Project description:Oxygen deficient zones (ODZs) are major sites of net natural oceanic nitrous oxide (N2O) production and emissions. In order to understand changes in the magnitude of N2O production in response to global change, knowledge on the individual contributions of the major microbial pathways (nitrification and denitrification) to N2O production and their regulation is needed. In the ODZ of the coastal area off Peru, the sensitivity of N2O production to oxygen and organic matter was investigated using 15N-tracer experiments in combination with qPCR and microarray analysis of total and active functional genes targeting archaeal amoA and nirS as marker genes for nitrification and denitrification, respectively. Denitrification was responsible for the highest N2O production with mean 8.7 nmol L-1 d-1 but up to 118 Â± 27.8 nmol L-1 d-1 just below the oxic-anoxic interface. Highest N2O production from AO of 0.16 Â± 0.003 nmol L-1 d-1 occurred in the upper oxycline at O2 concentrations of 10 - 30 Âµmol L-1 which coincided with highest archaeal amoA transcripts/genes. Oxygen responses of N2O production varied with substrate, but production and yields were generally highest below 10 Âµmol L-1 O2. Particulate organic matter additions increased N2O production by denitrification up to 5-fold suggesting increased N2O production during times of high particulate organic matter export. High N2O yields from ammonium oxidation of 2.1% were measured, but the overall contribution to N2O production stays an order of magnitude behind denitrification as an N2O source. Hence, these findings show that denitrification is the most important N2O production process in low oxygen conditions fueled by organic carbon supply which implies a positive feedback of the total oceanic N2O sources in response to increasing oceanic deoxygenation. [SUBMITTER_CITATION]: Frey, C., Bange, H. W., Achterberg, E. P., Jayakumar, A., Löscher, C. R., Arévalo-Martínez, D. L., León-Palmero, E., Sun, M., Sun, X., Xie, R. C., Oleynik, S., and Ward, B. B.: Regulation of nitrous oxide production in low-oxygen waters off the coast of Peru, Biogeosciences, 17, 2263-2287

			Action	DRS
	SRR10256989_1.fastq.gz	Fastqsanger.gz
	SRR10256989_2.fastq.gz	Fastqsanger.gz
	SRR10256990_1.fastq.gz	Fastqsanger.gz
	SRR10256990_2.fastq.gz	Fastqsanger.gz
	SRR10256991_1.fastq.gz	Fastqsanger.gz

Dataset Information

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets