The bacterium Zymomonas mobilis naturally produces ethanol at near theoretical maximum yields, making it of interest for industrial ethanol production. Zymomonas mobilis requires the vitamin pantothenate for growth. Here we characterized the genetic basis for the Z. mobilis pantothenate auxotrophy. We found that this auxotrophy is due to the absence of a single gene, panD, encoding aspartate-decarboxylase. Heterologous expression of Escherichia coli PanD in Z. mobilis or supplementation of the growth medium with the product of PanD activity, β-alanine, eliminated the need for exogenous pantothenate. We also determined that Z. mobilis IlvC, an enzyme better known for branched-chain amino acid synthesis, is required for pantothenate synthesis in Z. mobilis, as it compensates for the absence of PanE, another pantothenate synthesis pathway enzyme. In addition to contributing to an understanding of the nutritional requirements of Z. mobilis, our results have led to the design of a more cost-effective growth medium.
Individual species within microbial communities can combine their attributes to produce services that benefit society, such as the transformation of renewable resources into valuable chemicals. Under defined genetic and environmental conditions, fermentative Escherichia coli and phototrophic Rhodopseudomonas palustris exchange essential carbon and nitrogen, respectively, to establish a mutualistic relationship. In this relationship, each species produces H2 biofuel as a byproduct of its metabolism. However, the extent to which each species contributes to H2 production and the factors that influence their relative contributions were previously unknown. By comparing H2 yields in cocultures pairing R. palustris with either wild-type E. coli or a formate hydrogenlyase mutant that is incapable of H2 production, we determined the relative contribution of each species to total H2 production. Our results indicate that E. coli contributes between 32 and 86% of the H2 produced in coculture depending on the level of ammonium excreted by the R. palustris partner. The level of ammonium excretion influenced the time over which E. coliwas exposed to formate, the types of E. colifermentation products available to R. palustris, and the pH of the medium, all of which affected the contribution of each species to H2 production.
15Individual species within microbial communities can combine their attributes to produce services 16 that benefit society, such as the transformation of renewable resources into valuable chemicals. 17Under defined genetic and environmental conditions, fermentative Escherichia coli and 18phototrophic Rhodopseudomonas palustris exchange essential carbon and nitrogen, respectively, 19to establish a mutualistic relationship. In this relationship, each species produces H2 biofuel as a 20 byproduct of their metabolism. However, the extent to which each species contributes to H2 21 production and the factors that influence their relative contributions were previously unknown. 22By comparing H2 yields in cocultures pairing R. palustris with either wild-type E. coli or a 23 formate hydrogenlyase mutant that is incapable of H2 production, we determined the relative 24 contribution of each species to total H2 production. Our results indicate that E. coli contributes 25 between 32% and 86% of the H2 produced in coculture depending on the level of ammonium 26 excreted by the R. palustris partner. An R. palustris strain that stimulated rapid E. coli growth 27 through a high level of ammonium excretion resulted in earlier accumulation of formate and 28 acidic conditions that allowed E. coli to be the major contributor to H2 production. 29 30
Background/Objective: Patients with multiple chronic conditions require specialty consultations both within and across institutions for effective co-management of comorbidities. Poor communication during the referral process increases physician workload, patient burden and risks. Successful co-management relies on bi-directional information flow that supports interpersonal communication and establishment of clear tasks and responsibilities among physicians. However, flow of health information is often limited to specific health network access, phone calls, or faxes. Interpersonal communication is dependent on limited encounter notes. In this preliminary study, our objective was to understand how consultants’ notes support physician collaboration within and across health care institutions. Project Methods: To assess consultants’ notes, outpatient charts were randomly selected from the Indiana Network for Patient Care database representing consultations with five different specialties within the IU Health network, including referrals from within and outside of IU Health. The Quality of Consult Assessment tool was adapted to assess content of notes, emphasizing clinical recommendations, distribution of tasks and responsibilities, and communication plans. Results: Our sample included ten charts for patients who had comorbidities. All notes contained clinical recommendations that included an assessment and plan. 70% of notes contained explicit responsibilities of the consultants. Conversely, only one contained explicit responsibilities for referrers. Charts denoted reliance on support staff to send messages between referrers, consultants, and patients via phone and fax. Phone calls and faxes were more prominent in referrals across institutions. Conclusion and Impact: Our preliminary findings indicate that current clinical documentation supports specialty referrals for transitions of care rather than co-management of care. Difficulties in accessing patient charts across institutions leads to a lack of clinical context and workflow inefficiencies when attempting to co-manage care. These findings demonstrate negative implications in health outcomes for patients with multiple comorbidities that require more care coordination within and across institutions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.