High-consequence infectious diseases: the conception and development of a multi-disciplinary, interprofessional simulation training programme

BACKGROUND

High-consequence infectious diseases (HCIDs) represent a group of acute infectious diseases with the potential to impact healthcare systems and public health profoundly. Effective management requires a system-based strategy focused on early detection, initiation of infection prevention and control measures, and appropriate use of personal protective equipment (PPE). Inadequate training in the safe use of HCID PPE, and lack of familiarity with key processes such as HCID waste and spills management, exacerbates the risk posed to healthcare workers (HCWs). Enhanced training opportunities are required to ensure that staff are equipped with the necessary knowledge and capabilities to protect themselves from pathogen exposure and infection.

AIM

To create a bespoke interprofessional HCID simulation training programme.

METHODS

A detailed learning needs analysis was undertaken, which identified multiple areas amenable to educational intervention. A full-day HCID simulation programme was developed, providing HCWs the opportunity to practice and gain proficiency in various domains.

FINDINGS

Six interprofessional participants took part in the HCID simulation programme pilot. All six (100%) participants felt that the stated learning objectives had been achieved, and five and one participants found the programme to be extremely useful (83%) or very useful (17%), respectively. Following refinement based on pilot feedback, a further six courses have been run for 38 participants, of whom 97% found the programme to be extremely useful or very useful.

CONCLUSION

The development of a training intervention in the low-frequency, high-risk field of HCIDs had a positive impact. Given the disproportionate impact on HCWs at times of HCID outbreaks, more investment is needed to keep the workforce upskilled.

Bedside physician led US-guided supra-clavicular lymph node biopsy and ROSE (rapid on-site evaluation): SVC obstruction swift management in lung cancer

Superior vena cava obstruction (SVCO) is an oncological emergency and can often be linked to an underlying lung malignancy. Due to the potential life-threatening risks associated with SVCO, it necessitates urgent diagnosis and management. In this report, we discuss 3 case studies where the use of ultrasound-guided supraclavicular lymph node biopsy was used to obtain a biopsy from patients with SVCO, followed by rapid on-site evaluation (ROSE). The benefits of this technique ensure a more rapid histological diagnosis, while also involving a less invasive procedure for the patient. The histological diagnosis is essential in improving patient outcomes when treating those with SVCO as the recommended treatments vary depending on the underlying type of lung malignancy. Having this information can help the clinician swiftly employ the optimal treatment pathway for the patient.

The putative vacuolar processing enzyme gene TaVPE3cB is a candidate gene for wheat stem pith-thickness

KEY MESSAGE

The vacuolar processing enzyme gene TaVPE3cB is identified as a candidate gene for a QTL of wheat pith-thickness on chromosome 3B by BSR-seq and differential expression analyses. The high pith-thickness (PT) of the wheat stem could greatly enhance stem mechanical strength, especially the basal internodes which support the heavier upper part, such as upper stems, leaves and spikes. A QTL for PT in wheat was previously discovered on 3BL in a double haploid population of 'Westonia' × 'Kauz'. Here, a bulked segregant RNA-seq analysis was applied to identify candidate genes and develop associated SNP markers for PT. In this study, we aimed at screening differentially expressed genes (DEGs) and SNPs in the 3BL QTL interval. Sixteen DEGs were obtained based on BSR-seq and differential expression analyses. Twenty-four high-probability SNPs in eight genes were identified by comparing the allelic polymorphism in mRNA sequences between the high PT and low PT samples. Among them, six genes were confirmed to be associated with PT by qRT-PCR and sequencing. A putative vacuolar processing enzyme gene TaVPE3cB was screened out as a potential PT candidate gene in Australian wheat 'Westonia'. A robust SNP marker associated with TaVPE3cB was developed, which can assist in the introgression of TaVPE3cB.b in wheat breeding programs. In addition, we also discussed the function of other DEGs which may be related to pith development and programmed cell death (PCD). A five-level hierarchical regulation mechanism of stem pith PCD in wheat was proposed.

Physiological and cannabinoid responses of hemp (Cannabis sativa) to rock phosphate dust under tropical conditions

Growing a high-value crop such as industrial hemp (Cannabis sativa L.) in post-mining environments is economically and environmentally attractive but faces a range of biotic and abiotic challenges. An opportunity to investigate the cultivation of C. sativa presented itself as part of post-mining activities on Christmas Island (Australia) to profitably utilise disused phosphate (PS) quarries. Challenges to plant growth and cadmium (Cd) uptake were addressed in this study using potted plants under fully controlled conditions in a growth chamber. A complete nutritional spectrum, slow-release fertiliser was applied to all plants as a control treatment, and two levels of rock PS dust, a waste product of PS mining that contains 35% phosphorus (P) and 40ppm of naturally occurring Cd, were applied at 54 and 162gL-1 . After 12weeks, control plants (no PS dust) significantly differed in phenological development, with no flower production, lower aboveground biomass and reduced photosynthesis efficiency than those with P applied as rock dust. Compared with the controls, the 54gL-1 level of P dust increased shoot biomass by 38%, while 162gL-1 increased shoot biomass by 85%. The concentration of Δ9 -tetrahydrocannabinol also increased with the higher P levels. Cd uptake from PS dust by C. sativa was substantial and warrants further investigation. However, there was no increase in Cd content between the 54 and 162gL-1 application rates in seed and leaf. Results indicate that hemp could become a high-value crop on Christmas Island, with the readily available rock PS dust providing a source of P.

Current Progress and Future Prospect of Wheat Genetics Research towards an Enhanced Nitrogen Use Efficiency

To improve the yield and quality of wheat is of great importance for food security worldwide. One of the most effective and significant approaches to achieve this goal is to enhance the nitrogen use efficiency (NUE) in wheat. In this review, a comprehensive understanding of the factors involved in the process of the wheat nitrogen uptake, assimilation and remobilization of nitrogen in wheat were introduced. An appropriate definition of NUE is vital prior to its precise evaluation for the following gene identification and breeding process. Apart from grain yield (GY) and grain protein content (GPC), the commonly recognized major indicators of NUE, grain protein deviation (GPD) could also be considered as a potential trait for NUE evaluation. As a complex quantitative trait, NUE is affected by transporter proteins, kinases, transcription factors (TFs) and micro RNAs (miRNAs), which participate in the nitrogen uptake process, as well as key enzymes, circadian regulators, cross-talks between carbon metabolism, which are associated with nitrogen assimilation and remobilization. A series of quantitative genetic loci (QTLs) and linking markers were compiled in the hope to help discover more efficient and useful genetic resources for breeding program. For future NUE improvement, an exploration for other criteria during selection process that incorporates morphological, physiological and biochemical traits is needed. Applying new technologies from phenomics will allow high-throughput NUE phenotyping and accelerate the breeding process. A combination of multi-omics techniques and the previously verified QTLs and molecular markers will facilitate the NUE QTL-mapping and novel gene identification.

Bradyrhizobium archetypum sp. nov., Bradyrhizobium australiense sp. nov. and Bradyrhizobium murdochi sp. nov., isolated from nodules of legumes indigenous to Western Australia

The genus Bradyrhizobium is considered as the probable ancestor lineage of all rhizobia, broadly spread in a variety of ecosystems and with remarkable diversity. A polyphasic study was performed to characterize and clarify the taxonomic position of eight bradyrhizobial strains isolated from indigenous legumes to Western Australia. As expected for the genus, the 16S rRNA gene sequences were highly conserved, but the results of multilocus sequence analysis with four housekeeping genes (dnaK, glnII, gyrB and recA) confirmed three new distinct clades including the following strains: (1) WSM 1744^T, WSM 1736 and WSM 1737; (2) WSM 1791^T and WSM 1742; and (3) WSM 1741^T, WSM 1735 and WSM 1790. The highest ANI values of the three groups in relation to the closest type strains were 92.4, 92.3 and 93.3 %, respectively, below the threshold of species circumscription. The digital DNA-DNA hybridization analysis also confirmed new species descriptions, with less than 52 % relatedness with the closest type strains. The phylogeny of the symbiotic gene nodC clustered the eight strains into the symbiovar retamae, together with seven Bradyrhizobium type strains, sharing from 94.2-98.1 % nucleotide identity (NI), and less than 88.7 % NI with other related strains and symbiovars. Morpho-physiological, phylogenetics, genomic and symbiotic traits were determined for the new groups and our data support the description of three new species, Bradyrhizobium archetypum sp. nov., Bradyrhizobium australiense sp. nov. and Bradyrhizobium murdochi sp. nov., with WSM 1744^T (=CNPSo 4013^T=LMG 31646^T), WSM 1791^T (=CNPSo 4014^T=LMG 31647^T) and WSM 1741^T (=CNPSo 4020^T=LMG 31651^T) designated as type strains, respectively.

Transitioning from phosphate mining to agriculture: Responses to urea and slow release fertilizers for Sorghum bicolor

Globally, land-use transition from mining to agriculture is becoming increasingly attractive and necessary for many reasons. However, low levels of necessary plant nutrients, and high levels of heavy metals, can hamper plant growth, affecting yield, and potentially, food safety. In post-phosphate mining substrates, for example, nitrogen (N) is a key limiting nutrient, and, although legumes are planted prior to cereals, N supplementation is still necessary. We undertook two field trials on Christmas Island, Australia, to determine whether Sorghum bicolor could be grown successfully in a post-phosphate mining substrate. The first trial investigated N (urea) demand (amount of N required for adequate crop growth) for S. bicolor, and whether N addition could reduce the naturally occurring cadmium (Cd) concentrations in the crop. The second trial examined whether slow release nitrogen fertilizers (SRF) could replace urea to increase biomass and reduce Cd concentrations. Our first trial demonstrated that S. bicolor has a high N demand, with the highest biomass being recorded in the 160kg/ha urea treatment. However, plants treated with 80, 120 and 160kg/ha were not significantly different from one another. After 7weeks of growth, leaf Cd concentrations were significantly lower for all urea treatments compared with the control plants. However, after 23weeks, seed Cd concentrations did not differ across treatments. Our second trial demonstrated that the application of SRF (Macracote® and Sulsync®) and 160kg/ha urea significantly increased biomass above the control plants. There was, however, no treatment response in terms of Cd or N concentrations in the seed at final harvest. Thus, we have shown that N is currently critical for S. bicolor, even following legume cropping, and that high biomass and a significant reduction in Cd can be attained with appropriate levels of urea. Our work has important implications for cereal growth and food safety in post-mining agriculture.

Symbiotic Burkholderia Species Show Diverse Arrangements of nif/fix and nod Genes and Lack Typical High-Affinity Cytochrome cbb3 Oxidase Genes

Genome analysis of fourteen mimosoid and four papilionoid beta-rhizobia together with fourteen reference alpha-rhizobia for both nodulation (nod) and nitrogen-fixing (nif/fix) genes has shown phylogenetic congruence between 16S rRNA/MLSA (combined 16S rRNA gene sequencing and multilocus sequence analysis) and nif/fix genes, indicating a free-living diazotrophic ancestry of the beta-rhizobia. However, deeper genomic analysis revealed a complex symbiosis acquisition history in the beta-rhizobia that clearly separates the mimosoid and papilionoid nodulating groups. Mimosoid-nodulating beta-rhizobia have nod genes tightly clustered in the nodBCIJHASU operon, whereas papilionoid-nodulating Burkholderia have nodUSDABC and nodIJ genes, although their arrangement is not canonical because the nod genes are subdivided by the insertion of nif and other genes. Furthermore, the papilionoid Burkholderia spp. contain duplications of several nod and nif genes. The Burkholderia nifHDKEN and fixABC genes are very closely related to those found in free-living diazotrophs. In contrast, nifA is highly divergent between both groups, but the papilionoid species nifA is more similar to alpha-rhizobia nifA than to other groups. Surprisingly, for all Burkholderia, the fixNOQP and fixGHIS genes required for cbb3 cytochrome oxidase production and assembly are missing. In contrast, symbiotic Cupriavidus strains have fixNOQPGHIS genes, revealing a divergence in the evolution of two distinct electron transport chains required for nitrogen fixation within the beta-rhizobia.

High-quality permanent draft genome sequence of Ensifer medicae strain WSM244, a microsymbiont isolated from Medicago polymorpha growing in alkaline soil

Ensifer medicae WSM244 is an aerobic, motile, Gram-negative, non-spore-forming rod that can exist as a soil saprophyte or as a legume microsymbiont of Medicago species. WSM244 was isolated in 1979 from a nodule recovered from the roots of the annual Medicago polymorpha L. growing in alkaline soil (pH 8.0) in Tel Afer, Iraq. WSM244 is the only acid-sensitive E. medicae strain that has been sequenced to date. It is effective at fixing nitrogen with M. polymorpha L., as well as with more alkaline-adapted Medicago spp. such as M. littoralis Loisel., M. scutellata (L.) Mill., M. tornata (L.) Mill. and M. truncatula Gaertn. This strain is also effective with the perennial M. sativa L. Here we describe the features of E. medicae WSM244, together with genome sequence information and its annotation. The 6,650,282 bp high-quality permanent draft genome is arranged into 91 scaffolds of 91 contigs containing 6,427 protein-coding genes and 68 RNA-only encoding genes, and is one of the rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project proposal.

Bradyrhizobium neotropicale sp. nov., isolated from effective nodules of Centrolobium paraense

Root nodule bacteria were isolated from Centrolobium paraense Tul. grown in soils from the Amazon region, State of Roraima (Brazil). 16S rRNA gene sequence analysis of seven strains (BR 10247(T), BR 10296, BR 10297, BR 10298, BR 10299, BR 10300 and BR 10301) placed them in the genus Bradyrhizobium with the closest neighbours being the type strains of Bradyrhizobium paxllaeri (98.8 % similarity), Bradyrhizobium icense (98.8 %), Bradyrhizobium lablabi (98.7 %), Bradyrhizobium jicamae (98.6 %), Bradyrhizobium elkanii (98.6 %), Bradyrhizobium pachyrhizi (98.6 %) and Bradyrhizobium retamae (98.3 %). This high similarity, however, was not confirmed by the intergenic transcribed spacer (ITS) 16S-23S rRNA region sequence analysis nor by multi-locus sequence analysis. Phylogenetic analyses of five housekeeping genes (dnaK, glnII, gyrB, recA and rpoB) revealed Bradyrhizobium iriomotense EK05(T) ( = LMG 24129(T)) to be the most closely related type strain (95.7 % sequence similarity or less). Chemotaxonomic data, including fatty acid profiles [major components being C16 : 0 and summed feature 8 (18 : 1ω6c/18 : 1ω7c)], DNA G+C content, slow growth rate and carbon compound utilization patterns, supported the placement of the novel strains in the genus Bradyrhizobium. Results of DNA-DNA relatedness studies and physiological data (especially carbon source utilization) differentiated the strains from the closest recognized species of the genus Bradyrhizobium. Symbiosis-related genes for nodulation (nodC) and nitrogen fixation (nifH) placed the novel species in a new branch within the genus Bradyrhizobium. Based on the current data, these seven strains represent a novel species for which the name Bradyrhizobium neotropicale sp. nov. is proposed. The type strain is BR 10247(T) ( = HAMBI 3599(T)).

Bradyrhizobium ingae sp. nov., isolated from effective nodules of Inga laurina grown in Cerrado soil

Root-nodule bacteria were isolated from Inga laurina (Sw.) Willd. growing in the Cerrado Amazon region, State of Roraima, Brazil. The 16S rRNA gene sequences of six strains (BR 10250(T), BR 10248, BR 10249, BR 10251, BR 10252 and BR 10253) showed low similarities with currently described species of the genus Bradyrhizobium. Phylogenetic analyses of sequences of five housekeeping genes (dnaK, glnII, gyrB, recA and rpoB) revealed Bradyrhizobium iriomotense EK05(T) to be the closest type strain (97.4% sequence similarity or less). Chemotaxonomic data, including fatty acid profiles [with the major components C16:0 and summed feature 8 (C18:1ω6c/C18:1ω7c)], the slow growth rate and carbon compound utilization patterns supported the assignment of our strains to the genus Bradyrhizobium. Results from DNA-DNA hybridizations and physiological traits differentiated our strains from the closest related species of the genus Bradyrhizobium with validly published names. Sequences of symbiosis-related genes for nodulation (nodC) and nitrogen fixation (nifH) grouped together with those of B. iriomotense EK05(T) and Bradyrhizobium sp. strains BR 6610 (used as a commercial inoculant for Inga marginata in Brazil) and TUXTLAS-10 (previously observed in Central America). Based on these data, the six strains represent a novel species, for which the name Bradyrhizobium ingae sp. nov. is proposed. The type strain is BR 10250(T) ( = HAMBI 3600(T)).

Bradyrhizobium manausense sp. nov., isolated from effective nodules of Vigna unguiculata grown in Brazilian Amazonian rainforest soils

Root nodule bacteria were trapped within cowpea (Vigna unguiculata) in soils with different cultivation histories collected from the Amazonian rainforest in northern Brazil. Analysis of the 16S rRNA gene sequences of six strains (BR 3351(T), BR 3307, BR 3310, BR 3315, BR 3323 BR and BR 3361) isolated from cowpea nodules showed that they formed a distinct group within the genus Bradyrhizobium, which was separate from previously identified type strains. Phylogenetic analyses of three housekeeping genes (glnII, recA and rpoB) revealed that Bradyrhizobium huanghuaihaiense CCBAU 23303(T) was the most closely related type strain (96% sequence similarity or lower). Chemotaxonomic data, including fatty acid profiles (predominant fatty acids being C16 : 0 and summed feature 8), the slow growth rate and carbon compound utilization patterns supported the assignment of the strains to the genus Bradyrhizobium. The results of DNA-DNA hybridizations, antibiotic resistance and physiological tests differentiated these novel strains from the most closely related species of the genus Bradyrhizobium with validly published names. Symbiosis-related genes for nodulation (nodC) and nitrogen fixation (nifH) grouped the novel strains of the genus Bradyrhizobium together with Bradyrhizobium iriomotense strain EK05(T), with 94% and 96% sequence similarity, respectively. Based on these data, these six strains represent a novel species for which the name Brabyrhizobium manausense sp. nov. (BR 3351(T) = HAMBI 3596(T)), is proposed.

Genome sequence of the Ornithopus/Lupinus-nodulating Bradyrhizobium sp. strain WSM471

Bradyrhizobium sp. strain WSM471 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from an effective nitrogen- (N₂) fixing root nodule formed on the annual legume Ornithopus pinnatus (Miller) Druce growing at Oyster Harbour, Albany district, Western Australia in 1982. This strain is in commercial production as an inoculant for Lupinus and Ornithopus. Here we describe the features of Bradyrhizobium sp. strain WSM471, together with genome sequence information and annotation. The 7,784,016 bp high-quality-draft genome is arranged in 1 scaffold of 2 contigs, contains 7,372 protein-coding genes and 58 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program.

Genome sequence of the lupin-nodulating Bradyrhizobium sp. strain WSM1417

Bradyrhizobium sp. strain WSM1417 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from an effective nitrogen (N₂) fixing root nodule of Lupinus sp. collected in Papudo, Chile, in 1995. However, this microsymbiont is a poorly effective N₂ fixer with the legume host Lupinus angustifolius L.; a lupin species of considerable economic importance in both Chile and Australia. The symbiosis formed with L. angustifolius produces less than half of the dry matter achieved by the symbioses with commercial inoculant strains such as Bradyrhizobium sp. strain WSM471. Therefore, WSM1417 is an important candidate strain with which to investigate the genetics of effective N₂ fixation in the lupin-bradyrhizobia symbioses. Here we describe the features of Bradyrhizobium sp. strain WSM1417, together with genome sequence information and annotation. The 8,048,963 bp high-quality-draft genome is arranged in a single scaffold of 2 contigs, contains 7,695 protein-coding genes and 77 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program.

Genome sequence of the Trifolium rueppellianum -nodulating Rhizobium leguminosarum bv. trifolii strain WSM2012

Rhizobium leguminosarum bv. trifolii WSM2012 (syn. MAR1468) is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from an ineffective root nodule recovered from the roots of the annual clover Trifolium rueppellianum Fresen growing in Ethiopia. WSM2012 has a narrow, specialized host range for N2-fixation. Here we describe the features of R. leguminosarum bv. trifolii strain WSM2012, together with genome sequence information and annotation. The 7,180,565 bp high-quality-draft genome is arranged into 6 scaffolds of 68 contigs, contains 7,080 protein-coding genes and 86 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program.

Genome sequence of the clover-nodulating Rhizobium leguminosarum bv. trifolii strain TA1

Rhizobium leguminosarum bv. trifolii strain TA1 is an aerobic, motile, Gram-negative, non-spore-forming rod that is an effective nitrogen fixing microsymbiont on the perennial clovers originating from Europe and the Mediterranean basin. TA1 however is ineffective with many annual and perennial clovers originating from Africa and America. Here we describe the features of R. leguminosarum bv. trifolii strain TA1, together with genome sequence information and annotation. The 8,618,824 bp high-quality-draft genome is arranged in a 6 scaffold of 32 contigs, contains 8,493 protein-coding genes and 83 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program.

Genome sequence of the South American clover-nodulating Rhizobium leguminosarum bv. trifolii strain WSM597

Rhizobium leguminosarum bv. trifolii strain WSM597 is an aerobic, motile, Gram-negative, non-spore-forming rod isolated from a root nodule of the annual clover Trifolium pallidum L. growing at Glencoe Research Station near Tacuarembó, Uruguay. This strain is generally ineffective for nitrogen (N₂) fixation with clovers of Mediterranean, North American and African origin, but is effective on the South American perennial clover T. polymorphum Poir. Here we describe the features of R. leguminosarum bv. trifolii strain WSM597, together with genome sequence information and annotation. The 7,634,384 bp high-quality-draft genome is arranged in 2 scaffolds of 53 contigs, contains 7,394 protein-coding genes and 87 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program.

Complete genome sequence of Mesorhizobium australicum type strain (WSM2073(T))

Mesorhizobium australicum strain WSM2073^T was isolated from root nodules on the pasture legume Biserrula pelecinus growing in Australia in 2000. This aerobic, motile, gram negative, non-spore-forming rod is poorly effective in N₂ fixation on B. pelecinus and has gained the ability to nodulate B. pelecinus following in situ lateral transfer of a symbiosis island from the original inoculant strain for this legume, Mesorhizobium ciceri bv. biserrulae WSM1271. We describe that the genome size of M. australicum strain WSM2073^T is 6,200,534 bp encoding 6,013 protein-coding genes and 67 RNA-only encoding genes. This genome does not contain any plasmids but has a 455.7 kb genomic island from Mesorhizobium ciceri bv. biserrulae WSM1271 that has been integrated into a phenylalanine-tRNA gene.

Complete genome sequence of Rhizobium leguminosarum bv. trifolii strain WSM1325, an effective microsymbiont of annual Mediterranean clovers

Rhizobium leguminosarum bv trifolii is a soil-inhabiting bacterium that has the capacity to be an effective nitrogen fixing microsymbiont of a diverse range of annual Trifolium (clover) species. Strain WSM1325 is an aerobic, motile, non-spore forming, Gram-negative rod isolated from root nodules collected in 1993 from the Greek Island of Serifos. WSM1325 is produced commercially in Australia as an inoculant for a broad range of annual clovers of Mediterranean origin due to its superior attributes of saprophytic competence, nitrogen fixation and acid-tolerance. Here we describe the basic features of this organism, together with the complete genome sequence, and annotation. This is the first completed genome sequence for a microsymbiont of annual clovers. We reveal that its genome size is 7,418,122 bp encoding 7,232 protein-coding genes and 61 RNA-only encoding genes. This multipartite genome contains 6 distinct replicons; a chromosome of size 4,767,043 bp and 5 plasmids of size 828,924 bp, 660,973 bp, 516,088 bp, 350,312 bp and 294,782 bp.

Complete genome sequence of Rhizobium leguminosarum bv trifolii strain WSM2304, an effective microsymbiont of the South American clover Trifolium polymorphum

Rhizobium leguminosarum bv trifolii is the effective nitrogen fixing microsymbiont of a diverse range of annual and perennial Trifolium (clover) species. Strain WSM2304 is an aerobic, motile, non-spore forming, Gram-negative rod, isolated from Trifolium polymorphum in Uruguay in 1998. This microsymbiont predominated in the perennial grasslands of Glencoe Research Station, in Uruguay, to competitively nodulate its host, and fix atmospheric nitrogen. Here we describe the basic features of WSM2304, together with the complete genome sequence, and annotation. This is the first completed genome sequence for a nitrogen fixing microsymbiont of a clover species from the American center of origin. We reveal that its genome size is 6,872,702 bp encoding 6,643 protein-coding genes and 62 RNA only encoding genes. This multipartite genome was found to contain 5 distinct replicons; a chromosome of size 4,537,948 bp and four circular plasmids of size 1,266,105 bp, 501,946 bp, 308,747 bp and 257,956 bp.

Complete genome sequence of the Medicago microsymbiont Ensifer (Sinorhizobium) medicae strain WSM419

Ensifer (Sinorhizobium) medicae is an effective nitrogen fixing microsymbiont of a diverse range of annual Medicago (medic) species. Strain WSM419 is an aerobic, motile, non-spore forming, Gram-negative rod isolated from a M. murex root nodule collected in Sardinia, Italy in 1981. WSM419 was manufactured commercially in Australia as an inoculant for annual medics during 1985 to 1993 due to its nitrogen fixation, saprophytic competence and acid tolerance properties. Here we describe the basic features of this organism, together with the complete genome sequence, and annotation. This is the first report of a complete genome sequence for a microsymbiont of the group of annual medic species adapted to acid soils. We reveal that its genome size is 6,817,576 bp encoding 6,518 protein-coding genes and 81 RNA only encoding genes. The genome contains a chromosome of size 3,781,904 bp and 3 plasmids of size 1,570,951 bp, 1,245,408 bp and 219,313 bp. The smallest plasmid is a feature unique to this medic microsymbiont.

Ferroplasma cupricumulans sp. nov., a novel moderately thermophilic, acidophilic archaeon isolated from an industrial-scale chalcocite bioleach heap

A new species of Archaea was isolated from an industrial mineral sulphide bioleach heap. Strain BH2, a non-motile pleomorphic coccus, was capable of chemomixotrophic growth on ferrous sulphate and yeast extract. Growth was not supported in the absence of yeast extract. Phylogenetic analysis based on the 16S rRNA gene showed that strain BH2 was most closely related to the species Ferroplasma acidiphilum; however, it showed only 95% sequence similarity with this species. Strain BH2 had a temperature optimum of 53.6 degrees C and a temperature range for growth between 22 and 63 degrees C. Thus, it is the first moderately thermophilic member of the genus Ferroplasma. The optimum pH for the growth of the strain occurred between pH 1.0 and 1.2 and the lowest pH at which growth was observed was 0.4. Based on 16S rRNA gene sequence analysis and other physiological characteristics, strain BH2 constitutes a new species within the genus Ferroplasma. The name Ferroplasma cupricumulans is proposed for the new species and strain BH2 (DSM 16651) is proposed as the type strain.

Electrocardiographic findings in athletes: the prevalence of left ventricular hypertrophy and conduction defects

OBJECTIVES

To determine whether there are electrocardiographic differences or distinctive abnormalities between athletes and sedentary subjects, and to verify the relationship between vagal activity measured by heart rate variability (SD of all normal-to-normal intervals [SDNN]) and possible electrocardiographic abnormalities.

SUBJECTS AND METHODS

Resting electrocardiograms and heart rate variability measurements were performed separately during a single visit on 100 athletes and 50 nonathlete control subjects aged 18 to 55 years. The athletes were from the following various sports disciplines: long-distance running, mountain biking, cross-country skiing, biathlon, speed skating, swimming and triathlon.

RESULTS AND CONCLUSIONS

There were significantly longer RR intervals, PR intervals and QT intervals in athletes than in control subjects (all P<0.05). The QRS complex and QTc did not show significant differences (both P>0.05). The prevalence of left ventricular hypertrophy (LVH) and incomplete right bundle branch block (IRBBB) was 10% and 7%, respectively, in athletes, but these conditions were absent in control subjects; among athletes, 2% presented with both conditions. LVH and IRBBB were more common among long-distance runners (six of 14 and four of 14, respectively) and could be attributed to normal, long term adaptation to intense, repeated exercise. LVH was related to age (P=0.04), whereas IRBBB was influenced by the number of years of training in the respective sports discipline (P=0.03). The mean SDNN value was significantly more elevated in athletes (P=0.0001), reflecting a higher parasympathetic tone than in sedentary control subjects. However, there was no relationship between vagal activity and LVH or IRBBB (both P>0.05).