Project description:The halophilic γ-proteobacterium Halomonas elongata DSM 2581(T) thrives at high salinity by synthesizing and accumulating the compatible solute ectoine. Ectoine levels are highly regulated according to external salt levels but the overall picture of its metabolism and control is not well understood. Apart from its critical role in cell adaptation to halophilic environments, ectoine can be used as a stabilizer for enzymes and as a cell protectant in skin and health care applications and is thus produced annually on a scale of tons in an industrial process using H. elongata as producer strain. This paper presents the complete genome sequence of H. elongata (4,061,296 bp) and includes experiments and analysis identifying and characterizing the entire ectoine metabolism, including a newly discovered pathway for ectoine degradation and its cyclic connection to ectoine synthesis. The degradation of ectoine (doe) proceeds via hydrolysis of ectoine (DoeA) to Nα-acetyl-L-2,4-diaminobutyric acid, followed by deacetylation to diaminobutyric acid (DoeB). In H. elongata, diaminobutyric acid can either flow off to aspartate or re-enter the ectoine synthesis pathway, forming a cycle of ectoine synthesis and degradation. Genome comparison revealed that the ectoine degradation pathway exists predominantly in non-halophilic bacteria unable to synthesize ectoine. Based on the resulting genetic and biochemical data, a metabolic flux model of ectoine metabolism was derived that can be used to understand the way H. elongata survives under varying salt stresses and that provides a basis for a model-driven improvement of industrial ectoine production.
Project description:Halomonas strain GFAJ-1 was reported in Science magazine to be a remarkable microbe for which there was "arsenate in macromolecules that normally contain phosphate, most notably nucleic acids." The draft genome of the bacterium was determined (NCBI accession numbers AHBC01000001 through AHBC01000103). It appears to be a typical gamma proteobacterium.
Project description:BackgroundAntimicrobial Stewardship (AMS), the set of actions to ensure appropriate antimicrobial use, is increasingly considered a multidisciplinary endeavour. However, it is unclear how Dutch hospital-based nurses envision their contribution to AMS.ObjectiveTo explore the views and visions of Dutch bedside nurses on their role regarding appropriate antimicrobial use.MethodsA qualitative study using semi-structured interviews was conducted. Fourteen bedside nurses in nine different Dutch hospitals participated. Data were analysed using a thematic content analysis.ResultsNurses considered their role regarding appropriate use of antibiotics as an integral part of their daily nursing practice. They envisioned their future role as an expansion of their current practice, improving or intensifying this contribution. Prompting review of antimicrobial treatment by nurses was seen as regular practice. Ward rounds were considered the best moment to exert their nursing role, by showing leadership in communicating about different aspects of AMS. Patient advocacy ("striving for the best possible care for their patient") appears to be a driver of the nursing contribution. Nurses perceived a shared responsibility with prescribers on certain aspects of the antimicrobial treatment and wished for a clarification of this role. Education and cognitive reminders such as antibiotic checklist to be used in ward rounds, can support the uptake of the nurses' role.ConclusionNurses envision their future role in AMS as an enhanced, elaborated and empowered version of their current daily practice. Education, formal acknowledgment and increased awareness of the nursing role, may advance the contributing role nurses already have.
Project description:Halomonas axialensis is a halophilic bacterial species discovered near a deep-sea hydrothermal vent. Here, we report the first single closed genome sequence of the original strain, Halomonas axialensis strain Althf1. The genome was assembled by Nanopore sequencing and consisted of a single chromosome of 3.6 Mbp with 56.8% G+C content.
Project description:Halomonas axialensisACH-L-8, a deep-sea strain isolated from the South China Sea, has the ability to degrade aldehydes. Here, we present an annotated draft genome sequence of this species, which could provide fundamental molecular information on the aldehydes-degrading mechanism.
Project description:Halomonas sp. strain SL1, a halophilic gammaproteobacterium, was isolated from samples from the Great Salt Lake in Utah. We report here the draft genome sequence of SL1, which has an estimated total sequence length of 3.6 Mb.
Project description:We report the genome sequence of Halomonas sp. strain A3H3, a bacterium with a high tolerance to arsenite, isolated from multicontaminated sediments of the l'Estaque harbor in Marseille, France. The genome is composed of a 5,489,893-bp chromosome and a 157,085-bp plasmid.
Project description:Halomonas sp. strain KAO is an aerobic, Mn(II)-oxidizing, halophilic bacterium. The draft genome of the isolate contains 47 contigs encompassing 3.7 Mb and a GC content of 64.22%. This sequence will provide essential information for future studies of Mn(II) oxidation, particularly under halophilic conditions.
Project description:Increasing atmospheric partial pressure of CO2 (pCO2) is a major threat to coral reefs, but some argue that the threat is mitigated by factors such as the variability in the response of coral calcification to acidification, differences in bleaching susceptibility, and the potential for rapid adaptation to anthropogenic warming. However the evidence for these mitigating factors tends to involve experimental studies on corals, as opposed to coral reefs, and rarely includes the influence of multiple variables (e.g., temperature and acidification) within regimes that include diurnal and seasonal variability. Here, we demonstrate that the inclusion of all these factors results in the decalcification of patch-reefs under business-as-usual scenarios and reduced, although positive, calcification under reduced-emission scenarios. Primary productivity was found to remain constant across all scenarios, despite significant bleaching and coral mortality under both future scenarios. Daylight calcification decreased and nocturnal decalcification increased sharply from the preindustrial and control conditions to the future scenarios of low (reduced emissions) and high (business-as-usual) increases in pCO2. These changes coincided with deeply negative carbonate budgets, a shift toward smaller carbonate sediments, and an increase in the abundance of sediment microbes under the business-as-usual emission scenario. Experimental coral reefs demonstrated highest net calcification rates and lowest rates of coral mortality under preindustrial conditions, suggesting that reef processes may not have been able to keep pace with the relatively minor environmental changes that have occurred during the last century. Taken together, our results have serious implications for the future of coral reefs under business-as-usual environmental changes projected for the coming decades and century.
Project description:Halomonas meridiana strain Slthf1 (ATCC BAA-801) is a Gram-negative bacterium that was isolated from a thermal vent in 1998. Here, we report the complete genome sequence of this strain, which has a 3.6-Mbp genome, containing 3,400 protein-coding sequences.