A Novel Membrane-Associated Protein Aids Bacterial Colonization of Maize.

The soil environment affected by plant roots and their exudates, termed the rhizosphere, significantly impacts crop health and is an attractive target for engineering desirable agricultural traits. Engineering microbes in the rhizosphere is one approach to improving crop yields that directly minimizes the number of genetic modifications made to plants. Soil microbes have the potential to assist with nutrient acquisition, heat tolerance, and drought response if they can persist in the rhizosphere in the correct numbers.

Payment model impact on the resilience of rural communities: Exploratory study.

Objective: To explore rural physician perspectives on how remuneration impacted their experiences of contributing to community resilience during the COVID-19 pandemic.

Design: Exploratory, qualitative subanalysis.

Setting: Twenty-two rural communities in 4 Canadian provinces.

Expanding the synthetic biology toolbox of Cupriavidus necator for establishing fatty acid production.

The Gram-negative betaproteobacterium Cupriavidus necator is a chemolithotroph that can convert carbon dioxide into biomass. Cupriavidus necator has been engineered to produce a variety of high-value chemicals in the past. However, there is still a lack of a well-characterized toolbox for gene expression and genome engineering.

Scripting a new dialogue between diazotrophs and crops.

Diazotrophs are bacteria and archaea that can reduce atmospheric dinitrogen (N) into ammonium. Plant-diazotroph interactions have been explored for over a century as a nitrogen (N) source for crops to improve agricultural productivity and sustainability. This scientific quest has generated much information about the molecular mechanisms underlying the function, assembly, and regulation of nitrogenase, ammonium assimilation, and plant-diazotroph interactions.

Stepwise genetic engineering of Pseudomonas putida enables robust heterologous production of prodigiosin and glidobactin A.

Polyketide synthases (PKS) and nonribosomal peptide synthetases (NRPS) comprise biosynthetic pathways that provide access to diverse, often bioactive natural products. Metabolic engineering can improve production metrics to support characterization and drug-development studies, but often native hosts are difficult to genetically manipulate and/or culture. For this reason, heterologous expression is a common strategy for natural product discovery and characterization.

Genome Engineering of Yarrowia lipolytica with the PiggyBac Transposon System.

A mutant excision/integration piggyBac transposase can be used to seamlessly excise a chromosomally integrated, piggyBac-compatible selection marker cassette from the Yarrowia lipolytica genome. This piggyBac transposase-based genome engineering process allows for both positive selection of targeted homologous recombination events and scarless or footprint-free genome modifications after precise marker recovery. Residual non-native sequences left in the genome after marker excision can be minimized (0-4 nucleotides) or customized (user-defined except for a TTAA tetranucleotide).

A comparative analysis of single cell and droplet-based FACS for improving production phenotypes: Riboflavin overproduction in Yarrowia lipolytica.

Evolutionary approaches to strain engineering inherently require the identification of suitable selection techniques for the product and phenotype of interest. In this work, we undertake a comparative analysis of two related but functionally distinct methods of high-throughput screening: traditional single cell fluorescence activated cell sorting (single cell FACS) and microdroplet-enabled FACS (droplet FACS) using water/oil/water (w/o/w) emulsions. To do so, we first engineer and evolve the non-conventional yeast Yarrowia lipolytica for high extracellular production of riboflavin (vitamin B2), an innately fluorescent product.