Feed Your Friends: Do Plant Exudates Shape the Root Microbiome?

Plant health in natural environments depends on interactions with complex and dynamic communities comprising macro- and microorganisms. While many studies have provided insights into the composition of rhizosphere microbiomes (rhizobiomes), little is known about whether plants shape their rhizobiomes. Here, we discuss physiological factors of plants that may govern plant-microbe interactions, focusing on root physiology and the role of root exudates. Given that only a few plant transport proteins are known to be involved in root metabolite export, we suggest novel families putatively involved in this process. Finally, building off of the features discussed in this review, and in analogy to well-known symbioses, we elaborate on a possible sequence of events governing rhizobiome assembly

Metal fluoride inhibition of a P-type H⁺ pump:stabilization of the phosphoenzyme intermediate contributes to post-translational pump activation

The plasma membrane H(+)-ATPase is a P-type ATPase responsible for establishing electrochemical gradients across the plasma membrane in fungi and plants. This essential proton pump exists in two activity states: an autoinhibited basal state with a low turnover rate and a low H(+)/ATP coupling ratio and an activated state in which ATP hydrolysis is tightly coupled to proton transport. Here we characterize metal fluorides as inhibitors of the fungal enzyme in both states. In contrast to findings for other P-type ATPases, inhibition of the plasma membrane H(+)-ATPase by metal fluorides was partly reversible, and the stability of the inhibition varied with the activation state. Thus, the stability of the ATPase inhibitor complex decreased significantly when the pump transitioned from the activated to the basal state, particularly when using beryllium fluoride, which mimics the bound phosphate in the E2P conformational state. Taken together, our results indicate that the phosphate bond of the phosphoenzyme intermediate of H(+)-ATPases is labile in the basal state, which may provide an explanation for the low H(+)/ATP coupling ratio of these pumps in the basal state

Developing and piloting a cross-sectoral hospital pharmacist intervention for patients in transition between hospital and general practice

Background: Healthcare is challenged by a rapidly growing group of patients with multi-morbidity and polypharmacy. Increasing activity and specialization puts pressure on healthcare sectors. Medication errors in cross-sectoral transition of patients are often seen. The aim of the study was to explore drug-related problems (DRPs) in the transition of patients between sectors and to develop and pilot-test a cross-sectoral hospital pharmacist intervention to overcome some of these problems. Methods: DRPs in cross-sectoral transitions were explored from four perspectives; the literature, the primary and secondary healthcare sector and the patients. An intervention was developed from the findings through co-creation between pharmacists, doctors and a nurse. The intervention was piloted and evaluated from data on the included patients and the activities performed. Results: DRPs in transitions from general practice (GP) to hospital were caused by inadequate focus on updating the Shared Medication Record (SMR). For patients being discharged, DRPs were described with multiple facets; for example, missing information on medication changes, lacking patient involvement and problems with dose-dispensed medicine or electronic prescriptions. An intervention with a pharmacist in a shared employment between Hospital Pharmacy and GP was developed and piloted. The intervention included medication reconciliation and updating SMR for patients referred to hospital; and medication review, overview of medication changes and follow-up telephone calls for patients discharged from hospital. The intervention identified and solved several DRPs; in this way, medication errors were avoided. Access to health records in both sectors was important in the identification and resolution of DRPs. Conclusion: DRPs in cross-sectoral transitions are multifaceted and the experiences depend on the point of view. The cross-sectoral hospital pharmacist intervention identified and solved several DRPs and medication errors were avoided. The intervention made sense to both healthcare sectors and patients. Shared employment and unique access to health records in both sectors showed to be of importance in the identification and resolution of DRPs. Plain language summary Development and pilot-test of a pharmacist intervention for patients in transition between hospital and general practice Background: Healthcare is challenged by a rapidly growing group of patients with multiple chronic diseases treated with several drugs at the same time. The aim of the study was to explore drug-related problems in the transition of patients between the hospital and patients’ general practitioner and to develop and pilot-test a pharmacist intervention to overcome some of these problems. Methods: Drug-related problems in patient transitions were explored from the perspectives of the hospital, the general practitioner, the patients and the literature. An intervention was developed from the findings by pharmacists, doctors and a nurse. The intervention was pilot-tested and evaluated from the descriptions of the included patients and activities performed. Results: Drug-related problems in transitions from general practice to hospital were caused by inadequate focus on updating the Shared Medication Record. For patients being discharged, drug-related problems were related to for example missing information on medication changes sparse involvement of the patient in their own treatment problems with medicine dispensed on a dose dispensing machine at the local pharmacy. An intervention with a pharmacist in a shared employment between Hospital Pharmacy and general practice was developed and piloted. The intervention included talking to the patient about their medication and updating the Shared Medication Record for patients referred to hospital medication review, overview of medication changes and follow-up telephone calls for patients discharged from hospital to general practice. The intervention identified and solved several drug-related problems. Access to health records in both the general practice and at the hospital was important in the identification of drug-related problems. Conclusions: Drug-related problems in cross-sectoral transitions are multifaceted. The pharmacist intervention identified and solved several drug-related problems. The intervention made sense to the general practitioner, hospital and patients. Shared employment and unique access to health records in both the general practice and at the hospital showed to be of importance in the identification of drug-related problems

Specific activation of the plant P-type plasma membrane H⁺-ATPase by lysophospholipids depends on the autoinhibitory N- and C-terminal domains

Eukaryotic P-type plasma membrane H(+)-ATPases are primary active transport systems that are regulated at the post-translation level by cis-acting autoinhibitory domains, which can be relieved by protein kinase-mediated phosphorylation or binding of specific lipid species. Here we show that lysophospholipids specifically activate a plant plasma membrane H(+)-ATPase (Arabidopsis thaliana AHA2) by a mechanism that involves both cytoplasmic terminal domains of AHA2, whereas they have no effect on the fungal counterpart (Saccharomyces cerevisiae Pma1p). The activation was dependent on the glycerol backbone of the lysophospholipid and increased with acyl chain length, whereas the headgroup had little effect on activation. Activation of the plant pump by lysophospholipids did not involve the penultimate residue, Thr-947, which is known to be phosphorylated as part of a binding site for activating 14-3-3 protein, but was critically dependent on a single autoinhibitory residue (Leu-919) upstream of the C-terminal cytoplasmic domain in AHA2. A corresponding residue is absent in the fungal counterpart. These data indicate that plant plasma membrane H(+)-ATPases evolved as specific receptors for lysophospholipids and support the hypothesis that lysophospholipids are important plant signaling molecules