Increased metabolic potential of Rhizobium spp. is associated with bacterial competitiveness

2007 ◽  
Vol 53 (8) ◽  
pp. 957-967 ◽  
Author(s):  
Jerzy Wielbo ◽  
Monika Marek-Kozaczuk ◽  
Agnieszka Kubik-Komar ◽  
Anna Skorupska
Keyword(s):  
Rhizobium Leguminosarum ◽  
Growth Promotion ◽  
High Rate ◽  
Energy Sources ◽  
Metabolic Potential ◽  
Wide Range ◽  
Nodulation Competitiveness ◽  
Gusa Gene ◽  
Rhizobium Spp ◽  
Metabolic Properties

Of 105 rhizobial isolates obtained from nodules of commonly cultivated legumes, we selected 19 strains on the basis of a high rate of symbiotic plant growth promotion. Individual strains within the species Rhizobium leguminosarum bv. trifolii , R. leguminosarum bv. viciae , and Rhizobium etli displayed variation not only in plasmid sizes and numbers but also in the chromosomal 16S–23S internal transcribed spacer. The strains were tagged with gusA gene and their competitiveness was examined in relation to an indigenous population of rhizobia under greenhouse conditions. A group of 9 strains was thus isolated that were competitive in relation to native rhizobia in pot experiments. Nineteen selected competitive and uncompetitive strains were examined with respect to their ability to utilize various carbon and energy sources by means of commercial Biolog GN2 microplate test. The ability of the selected strains to metabolize a wide range of nutrients differed markedly and the competitive strains were able to utilize more carbon and energy sources than uncompetitive ones. A major difference concerned the utilization of amino and organic acids, which were metabolized by most of the competitive and only a few uncompetitive strains, whereas sugars and their derivatives were commonly utilized by both groups of strains. A statistically significant correlation between the ability to metabolize a broad range of substrates and nodulation competitiveness was found, indicating that metabolic properties may be an essential trait in determining the competitiveness of rhizobia.

Associated microflora of medicinal ferns: biotechnological potentials and possible applications

2016 ◽  
Vol 5 (03) ◽  
pp. 4927 ◽  
Author(s):  
Shubhi Srivastava ◽  
Paul A. K.
Keyword(s):  
Secondary Metabolites ◽  
Growth Promotion ◽  
Biological Activities ◽  
Hydrolytic Enzymes ◽  
In Vitro Production ◽  
Wide Range ◽  
Negative Effect ◽  
Bacteria And Fungi

Plant associated microorganisms that colonize the upper and internal tissues of roots, stems, leaves and flowers of healthy plants without causing any visible harmful or negative effect on their host. Diversity of microbes have been extensively studied in a wide variety of vascular plants and shown to promote plant establishment, growth and development and impart resistance against pathogenic infections. Ferns and their associated microbes have also attracted the attention of the scientific communities as sources of novel bioactive secondary metabolites. The ferns and fern alleles, which are well adapted to diverse environmental conditions, produce various secondary metabolites such as flavonoids, steroids, alkaloids, phenols, triterpenoid compounds, variety of amino acids and fatty acids along with some unique metabolites as adaptive features and are traditionally used for human health and medicine. In this review attention has been focused to prepare a comprehensive account of ethnomedicinal properties of some common ferns and fern alleles. Association of bacteria and fungi in the rhizosphere, phyllosphere and endosphere of these medicinally important ferns and their interaction with the host plant has been emphasized keeping in view their possible biotechnological potentials and applications. The processes of host-microbe interaction leading to establishment and colonization of endophytes are less-well characterized in comparison to rhizospheric and phyllospheric microflora. However, the endophytes are possessing same characteristics as rhizospheric and phyllospheric to stimulate the in vivo synthesis as well as in vitro production of secondary metabolites with a wide range of biological activities such as plant growth promotion by production of phytohormones, siderophores, fixation of nitrogen, and phosphate solubilization. Synthesis of pharmaceutically important products such as anticancer compounds, antioxidants, antimicrobials, antiviral substances and hydrolytic enzymes could be some of the promising areas of research and commercial exploitation.

scholarly journals Growth Promotion or Osmotic Stress Response: How SNF1-Related Protein Kinase 2 (SnRK2) Kinases Are Activated and Manage Intracellular Signaling in Plants

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1443
Author(s):  
Yoshiaki Kamiyama ◽  
Sotaro Katagiri ◽  
Taishi Umezawa
Keyword(s):  
Protein Kinase ◽  
Plant Growth ◽  
Osmotic Stress ◽  
Protein Function ◽  
Intracellular Signaling ◽  
Growth Promotion ◽  
Research Field ◽  
Dependent Manner ◽  
Related Protein ◽  
Wide Range

Reversible phosphorylation is a major mechanism for regulating protein function and controls a wide range of cellular functions including responses to external stimuli. The plant-specific SNF1-related protein kinase 2s (SnRK2s) function as central regulators of plant growth and development, as well as tolerance to multiple abiotic stresses. Although the activity of SnRK2s is tightly regulated in a phytohormone abscisic acid (ABA)-dependent manner, recent investigations have revealed that SnRK2s can be activated by group B Raf-like protein kinases independently of ABA. Furthermore, evidence is accumulating that SnRK2s modulate plant growth through regulation of target of rapamycin (TOR) signaling. Here, we summarize recent advances in knowledge of how SnRK2s mediate plant growth and osmotic stress signaling and discuss future challenges in this research field.

scholarly journals Genome analysis of Pseudomonas sp. OF001 and Rubrivivax sp. A210 suggests multicopper oxidases catalyze manganese oxidation required for cylindrospermopsin transformation

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Erika Berenice Martínez-Ruiz ◽  
Myriel Cooper ◽  
Jimena Barrero-Canosa ◽  
Mindia A. S. Haryono ◽  
Irina Bessarab ◽  
...  
Keyword(s):  
Calvin Cycle ◽  
Multicopper Oxidase ◽  
Genomic Islands ◽  
Biotechnological Applications ◽  
High Similarity ◽  
Multicopper Oxidases ◽  
Metabolic Potential ◽  
Natural Habitats ◽  
Manganese Oxidation ◽  
Wide Range

Abstract Background Cylindrospermopsin is a highly persistent cyanobacterial secondary metabolite toxic to humans and other living organisms. Strain OF001 and A210 are manganese-oxidizing bacteria (MOB) able to transform cylindrospermopsin during the oxidation of Mn2+. So far, the enzymes involved in manganese oxidation in strain OF001 and A210 are unknown. Therefore, we analyze the genomes of two cylindrospermopsin-transforming MOB, Pseudomonas sp. OF001 and Rubrivivax sp. A210, to identify enzymes that could catalyze the oxidation of Mn2+. We also investigated specific metabolic features related to pollutant degradation and explored the metabolic potential of these two MOB with respect to the role they may play in biotechnological applications and/or in the environment. Results Strain OF001 encodes two multicopper oxidases and one haem peroxidase potentially involved in Mn2+ oxidation, with a high similarity to manganese-oxidizing enzymes described for Pseudomonas putida GB-1 (80, 83 and 42% respectively). Strain A210 encodes one multicopper oxidase potentially involved in Mn2+ oxidation, with a high similarity (59%) to the manganese-oxidizing multicopper oxidase in Leptothrix discophora SS-1. Strain OF001 and A210 have genes that might confer them the ability to remove aromatic compounds via the catechol meta- and ortho-cleavage pathway, respectively. Based on the genomic content, both strains may grow over a wide range of O2 concentrations, including microaerophilic conditions, fix nitrogen, and reduce nitrate and sulfate in an assimilatory fashion. Moreover, the strain A210 encodes genes which may convey the ability to reduce nitrate in a dissimilatory manner, and fix carbon via the Calvin cycle. Both MOB encode CRISPR-Cas systems, several predicted genomic islands, and phage proteins, which likely contribute to their genome plasticity. Conclusions The genomes of Pseudomonas sp. OF001 and Rubrivivax sp. A210 encode sequences with high similarity to already described MCOs which may catalyze manganese oxidation required for cylindrospermopsin transformation. Furthermore, the analysis of the general metabolism of two MOB strains may contribute to a better understanding of the niches of cylindrospermopsin-removing MOB in natural habitats and their implementation in biotechnological applications to treat water.

scholarly journals Exploring the Relationship between Sustainable Projects and Institutional Isomorphisms: A Project Typology

2020 ◽  
Vol 12 (9) ◽  
pp. 3668 ◽  
Author(s):  
Rakan Alyamani ◽  
Suzanna Long ◽  
Mohammad Nurunnabi
Keyword(s):  
Information Exchange ◽  
External Factors ◽  
Energy Sources ◽  
Management Research ◽  
Experience Levels ◽  
Wide Range ◽  
Institutional Influences ◽  
Change Level ◽  
The Relationship ◽  
Sustainable Projects

With the increase in awareness about the wide range of issues and adverse effects associated with the use of conventional energy sources came an increase in project management research related to sustainability and sustainable development. Part of that research is devoted to the development of sustainable project typologies that classify projects based on a variety of external factors that can significantly impact these projects. This research focuses on developing a sustainable project typology that classifies sustainable projects based on the external institutional influences. The typology explores the influence of the coercive, normative, and mimetic institutional isomorphisms on the expected level of change, level of uncertainty, project team skills and experience levels, and the level of technology information exchange in sustainable projects. Two case studies are presented to demonstrate the use of the typology to classify sustainable projects based on the external institutional influences.

Sustaining Research-Based Practices in Reading

1999 ◽  
Vol 20 (5) ◽  
pp. 263-287 ◽  
Author(s):  
Janette K. Klingner ◽  
Sharon Vaughn ◽  
Marie Tejero Hughes ◽  
Maria Elena Arguelles
Keyword(s):  
Instructional Practices ◽  
High Rate ◽  
Strategic Reading ◽  
School Year ◽  
Wide Range ◽  
Sustained Use ◽  
Development Experience ◽  
Collaborative Strategic Reading ◽  
Research Based Practices ◽  
Over Time

This study examined the extent to which the reading instructional practices learned by a cohort of teachers who participated in an intensive, yearlong professional development experience during the 1994-1995 school year have been sustained and modified over time. Teachers learned three multileveled practices—partner reading, collaborative strategic reading, and making words—that promote gains in reading for students from a wide range of achievement levels. Teachers were observed and interviewed 3 years later to determine the extent to which they continued to implement the practices, the ways in which they modified them, and factors that influenced their sustained use of the practices. With the exception of one teacher, all the teachers sustained one or more of the three practices at a high rate.

MAIN FEATURES AND TRENDS OF DEVELOPMENT OF THE SERVICE MARKET

2017 ◽  
Author(s):  
Larysa Getman ◽  
Keyword(s):  
Customer Loyalty ◽  
Consumer Choice ◽  
Information Technologies ◽  
Service Sector ◽  
Supply And Demand ◽  
High Rate ◽  
Barriers To Entry ◽  
Relevant Market ◽  
Service Market ◽  
Wide Range

The article discusses approaches to the interpretation of the concept of a service, its specific differences from a physical product and the main features as an object of purchase and sale in the relevant market. Based on the analysis and systematization of existing scientific views, the main features of the service market and the features of the interaction of supply and demand in the service sector are revealed. The practice of functioning of the service market demonstrates the high dynamics of market processes, a pronounced segmentation of demand for services, a high degree of differentiation of services, a high rate of capital turnover and the important role of non-price barriers to entry into the market. The essence and value of the customer's customer loyalty for successful commercial activities and increasing the competitiveness of the manufacturer-supplier of the service has been investigated. Loyalty becomes an indicator of business performance and its ability to innovate. A customer-oriented business philosophy, where a wide range of factors of influence on the formation of customer loyalty is taken into account and used, will allow the company to count on long-term relationships with the consumer and will attract new customers through his positive experience. The possibilities and features of the application of competitive strategies by firms in the field of service activities were analyzed. The main trends in the development of the services market in the current stage, namely the processes of its digitalization, have been investigated. The buyer today is interested not only in price and quality, but also in good service. If a company meets customer service demand through the introduction of chat bots, self- service terminals, mobile applications, etc., then this contributes to the formation of a positive customer experience, which ultimately increases sales. The features and advantages of using information technologies both in business activities and in the implementation of consumer choice have been determined.

scholarly journals Virulence and Metabolic Characteristics of Salmonella enterica Serovar Enteritidis Strains with DifferentsefDVariants in Hens

2012 ◽  
Vol 78 (18) ◽  
pp. 6405-6412 ◽  
Author(s):  
Cesar A. Morales ◽  
Jean Guard ◽  
Roxana Sanchez-Ingunza ◽  
Devendra H. Shah ◽  
Mark Harrison
Keyword(s):  
Salmonella Enterica ◽  
Egg Production ◽  
The Body ◽  
Wild Type ◽  
Salmonella Enterica Serovar Enteritidis ◽  
Blood Calcium ◽  
Content Type ◽  
Metabolic Characteristics ◽  
Wide Range ◽  
Metabolic Properties

ABSTRACTSalmonella entericaserovar Enteritidis is one of a fewSalmonella entericaserotypes that has SEF14 fimbriae encoded by thesefoperon, which consists of 4 cotranscribed genes,sefABCD, regulated bysefR. A parental strain was used to construct asefDmutant and its complement, and all 3 strains were compared for gene expression, metabolic properties, and virulence characteristics in hens. Transcription ofsefDby wild type was suppressed at 42°C and absent for the mutant under conditions where the complemented mutant had 103times higher transcription. Growth of the complemented mutant was restricted in comparison to that of the mutant and wild type. Hens infected with the wild type and mutant showed decreased blood calcium and egg production, but infection with the complemented mutant did not. Thus, the absence ofsefDcorrelated with increased metabolic capacity and enhanced virulence of the pathogen. These results suggest that any contribution thatsefDmakes to egg contamination is either unknown or would be limited to early transmission from the environment to the host. Absence ofsefD, either through mutation or by suppression of transcription at the body temperature of the host, may contribute to the virulence ofSalmonella entericaby facilitating growth on a wide range of metabolites.

Genetic characterization of Rhizobium sp. strain TAL1145 that nodulates tree legumes

1994 ◽  
Vol 40 (3) ◽  
pp. 208-215 ◽  
Author(s):  
M. L. C. George ◽  
J. P. W. Young ◽  
D. Borthakur
Keyword(s):  
Rhizobium Leguminosarum ◽  
Genetic Characterization ◽  
Rhizobium Meliloti ◽  
Wild Type ◽  
Tree Legumes ◽  
Wide Range ◽  
The Common ◽  
Rrna Sequences ◽  
Rhizobium Sp

Rhizobium sp. strain TALI 145 nodulates Leucaena ieucocephaia and Phaseolus vulgaris, in addition to a wide range of tropical tree legumes. Six overlapping clones that complemented nodulation defects in leucaena and bean rhizobia were isolated and a 40-kb map of the symbiosis region was constructed. The common nod and nifA genes were situated approximately 17 kb apart, with the nodlJ genes in between. These clones enabled a derivative of TAL1145 carrying a partially deleted pSym to form ineffective nodules on both leucaena and bean, and a similar derivative of Rhizobium etli TAL182 to form ineffective nodules on bean. When two representative clones, pUHR9 and pUHR114, were each transferred to wild-type rhizobial strains, they allowed ineffective nodulation by Rhizobium meliloti on both leucaena and bean and by Rhizobium leguminosarum bv. viciae on bean. Transconjugants of R. leguminosarum bv. trifolii formed effective nodules on leucaena and ineffective nodules on bean. Tn5 mutagenesis of the symbiosis region resulted in a variety of nodulation and fixation phenotypes on leucaena and bean. On the basis of 16S rRNA sequences, TAL1145 was found to be distinct from both R. tropici and NGR234, the two groups of leucaena symbionts that were previously described.Key words: Rhizobium, Leucaena leucocephala, nodulation, nitrogen fixation.

scholarly journals The Captain’s View: A Novel Radiographic View to Assess Axial Alignment of the Calcaneus

2019 ◽  
Vol 4 (4) ◽  
pp. 2473011419S0042
Author(s):  
Brian Velasco ◽  
Bruno Moura ◽  
John Kwon
Keyword(s):  
Soft Tissues ◽  
Articular Surface ◽  
Lateral Wall ◽  
Varus Deformity ◽  
High Rate ◽  
Clear Correlation ◽  
Lateral Side ◽  
Axial Alignment ◽  
Wide Range ◽  
Fresh Frozen

Category: Hindfoot, Trauma Introduction/Purpose: The axial alignment of the calcaneus has paramount importance in the management of these fractures. The Harris view has long stood as the recommended radiograph to assess axial alignment. However, given the obliquity at which the radiograph is obtained, it doesn´t represent a true axial view and is subject to inaccuracies secondary to rotational malpositioning of the foot and mismeasurement of angulation. Multiple reports have described the axial alignment as a surgical outcome, but usually this assessment of the residual deformity have no described method. The objectives of this study are to evaluate the capacity of Harris view to assess axial alignment in a cadaveric model and to describe the use of a true AP view of the calcaneus that we have named Captain´s view. Methods: Five below knee amputated fresh-frozen cadaveric specimens were used in the study. For each specimen, the soft tissues over the lateral side were removed to access to the lateral wall. A small wedge of the cuboid was removed to visualize the center of the calcaneocuboid articular surface. LCA-guide and a cannulated drill were used to create a tunnel in the axis of the calcaneus. An oblique osteotomy was performed in order to simulate a non-comminuted fracture. Varus deformity was created by inserting solid radiolucent wedges into the osteotomy to create models of 10, 20, and 30 degrees of varus angulation. Harris and Captain views were obtained for each specimen with 0 (control), 10, 20, and 30 degrees of varus malalignment. Measurements of the deformity were made digitally on each fluoroscopic image. Results: The average degrees of varus in Harris views were 10,9 (5,5-16); 11,5 (8,2-13,6); and 18,3 (13,3-23,6) for 10,20 and 30 degrees of deformity respectively. The average degrees of varus in Captain´s view were 13,0 (7,3-20,9); 18,4 (11,7-23,5); and 28,2 (24,4-31,1) for 10,20 and 30 degrees of deformity respectively. The average degrees of error for varus deformity in Harris views were 4,1 (41%); 8,4 (42%) and 11,6 (39%) for 10,20 and 30 degrees of deformity respectively. The average degrees of error for varus deformity in Captain´s views were 4,8 (48%); 3,6 (18%) and 2,8 (8%) for 10,20 and 30 degrees of deformity respectively. Conclusion: The results of this study show a high rate of mismeasurement for both radiographic views. Despite the average angles have a clear correlation with the severity of varus, the wide range of error observed between specimens make this assessment unreliable and inaccurate. We observed an improvement of accuracy of captain´s view for more severe deformities, but not with Harris views which maintain a 40% mismeasurement in all the settings. Therefore, intraoperative Harris views should not be used in isolation to evaluate axial alignment and Captain´s view provides an additional perspective that can be useful to rule out severe deformities.

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