Engineered Root Bacteria Release Plant-Available Phosphate from Phytate.

Microorganisms that release plant-available phosphate from natural soil phosphate stores may serve as biological alternatives to costly and environmentally damaging phosphate fertilizers. To explore this possibility, we engineered a collection of root bacteria to release plant-available orthophosphate from phytate, an abundant phosphate source in many soils. We identified 82 phylogenetically diverse phytase genes, refactored their sequences for optimal expression in Proteobacteria, and then synthesized and engineered them into the genomes of three root-colonizing bacteria. Liquid culture assays revealed 41 engineered strains with high levels of phytate hydrolysis. Among these, we identified 12 strains across three bacterial hosts that confer a growth advantage on the model plant Arabidopsis thaliana when phytate is the sole phosphate source. These data demonstrate that DNA synthesis approaches can be used to generate plant-associated strains with novel phosphate-solubilizing capabilities.IMPORTANCE Phosphate fertilizers are essential for high-yield agriculture yet are costly and environmentally damaging. Microbes that release soluble phosphate from naturally occurring sources in the soil are appealing, as they may reduce the need for such fertilizers. In this study, we used synthetic biology approaches to create a collection of engineered root-associated microbes with the ability to release phosphate from phytate. We demonstrate that these strains improve plant growth under phosphorus-limited conditions. This represents a first step in the development of phosphate-mining bacteria for future use in crop systems.

Evaluation of the National Database of Nursing Quality Indicators (NDNQI) Training Program on Pressure Ulcers.

The National Database of Nursing Quality Indicators (NDNQI) Pressure Ulcer Training Program was developed to improve nursing accuracy and reliability in identifying and staging pressure ulcers and differentiating hospital- and unit-acquired from community-acquired pressure ulcers. Of 5,200 individuals who completed the training program within 5 months of release, 937 provided written evaluation comments. Four major themes emerged from content analysis of the evaluation remarks: pressure ulcer and other wound pictures; accuracy and clarity of content; program design and technology; and the educational/informational experience. Reviewers most frequently commented on their positive learning experience. Program components that enhanced the educational experience included the array of pressure ulcer pictures at each stage and pictures of other wounds. Clarity of content, program design, and technological problems were barriers to reviewer satisfaction. Findings suggest the NDNQI Pressure Ulcer Training Program was effective for educating staff nurses on pressure ulcer identification and staging.