Biochemical investigation of the tryptophan biosynthetic enzyme anthranilate phosphoribosyltransferase in plants.

While mammals require the essential amino acid tryptophan (Trp) in their diet, plants and microorganisms synthesize Trp de novo. The five-step Trp pathway starts with the shikimate pathway product, chorismate. Chorismate is converted to the aromatic compound anthranilate, which is then conjugated to a phosphoribosyl sugar in the second step by anthranilate phosphoribosyltransferase (PAT1). As a single-copy gene in plants, all fixed carbon flux to indole and Trp for protein synthesis, specialized metabolism, and auxin hormone biosynthesis proceeds through PAT1. While bacterial PAT1s have been studied extensively, plant PAT1s have escaped biochemical characterization. Using a structure model, we identified putative active site residues that were variable across plants and kinetically characterized six PAT1s (Arabidopsis thaliana (thale cress), Citrus sinensis (sweet orange), Pistacia vera (pistachio), Juglans regia (English walnut), Selaginella moellendorffii (spike moss), and Physcomitrium patens (spreading earth-moss)). We probed the catalytic efficiency, substrate promiscuity, and regulation of these six enzymes and found that the C. sinensis PAT1 is highly specific for its cognate substrate, anthranilate. Investigations of site-directed mutants of the A. thaliana PAT1 uncovered an active site residue that contributes to promiscuity. While Trp inhibits bacterial PAT1 enzymes, the six plant PAT1s that we tested were not modulated by Trp. Instead, the P. patens PAT1 was inhibited by tyrosine, and the S. moellendorffii PAT1 was inhibited by phenylalanine. This structure-informed biochemical examination identified variations in activity, efficiency, specificity, and enzyme-level regulation across PAT1s from evolutionarily diverse plants.

Through the eyes of hospital-based healthcare professionals: exploring their lived experience during the COVID-19 pandemic.

OBJECTIVE: The spread of the COVID-19 virus has caused an unforeseen strain on the healthcare system and particularly on healthcare workers (HCW). In this study, 1 year after the COVID-19 pandemic began, we used photovoice, a visual photographic approach, to understand HCW needs, concerns and resilience and to determine improvement strategies aligned with the HCW-described challenges. METHODS: Using a qualitative design, HCW were recruited from a single Western Canadian hospital, voluntarily submitting a photographic image and narrative that depicts their experiences. An artist artistically enhanced the photovoice submissions, which were then displayed at the hospital-based art gallery for public display. A survey was used to collect feedback from gallery viewers. Inductive thematic analysis was completed identifying themes from the photovoice narratives and survey comments, aiding the identification of recommendations. RESULTS: There were 25 submissions, and 1281 individuals viewed the art exhibit. Six themes emerged: (1) hopeful and resilient, (2) pandemic fatigue-negative mental and physical states, (3) personal protective equipment is our armour but masks who we are, (4) human connection, (5) responsibility, preparation and obligation and (6) technology surge. According to survey results from the art exhibit, the use of photovoice was a creative method that personalised the HCW experience and validated viewers' perceptions of the difficulties faced by HCW. Ten improvement strategies that were aligned with the described challenges were identified. CONCLUSION: The ongoing COVID-19 pandemic continues to strain HCW. Photovoice has great potential in the professional clinical setting to provide unique insights that narrative language alone cannot capture. Future research exploring the longitudinal impact of COVID-19, reviewing photographs at different timepoints could be beneficial. Using this method as a creative outlet intervention and evaluating participation artistic experience may offer additional insights to further support both HCW and patients.

Patient feedback identifies "Rheum" to improve clinic visit preparedness.

Healthcare providers and administrators are incorporating patient feedback to drive local health system improvement. Improvement interventions, including patient feedback, guided a novel approach for rheumatology patient appointment preparedness. We tested the interventions in a single rheumatology clinic. A comprehensive patient questionnaire was developed by assessing patients' clinic access using patient journey mapping. The questionnaire was administered to a random cohort of 125 rheumatology patients about their feedback on pre-clinic practices. From the responses, modifications were made to existing administrative practices within the clinic. The modified practices were tested with an additional cohort of 10 patients aligned to one rheumatologist, assessing overall patients' preparedness and clinic visit cycle time. It was identified from the questionnaire that during appointment booking, inconsistent pre-clinic planning information was communicated to patients and the appointment package did not support patient preparedness, resulting in extending clinic visits. Standardization of the appointment phone call script, updating the appointment package, and inclusion of a clinic visit preparation checklist, reduced the clinic visit cycle time by 10 minutes for new patients, and 5 minutes for existing patients. The participating clinic rheumatologist also perceived improved patient preparedness and clinic visit flow based on the modified practices. In this study, patient feedback was used to identify patient-centred interventions to improve patient preparedness at clinic visits. The interventions developed were simple and easy to incorporate into practice. Systematic collection of and strategies based on patient feedback was determined to be a valid, meaningful method for incorporating clinical quality improvement. KEY POINTS : • Structured patient feedback can inform quality improvement practices in a rheumatological clinic setting. • A patient journey map outlining healthcare clinic access can help to understand patient experiences and needs. • Simple, patient-centred interventions, such as an appointment package and a consistent telephone reminder script, improved patient preparedness and reduced average clinic cycle time.