Nomenclature Abstract for Rhizobium tropici Martínez-Romero et al. 1991 emend. Hördt et al. 2020.

Lysyl-phosphatidylglycerol (LPG) is a well-known membrane lipid in several gram-positive bacteria but is almost unheard of in gram-negative bacteria. In Staphylococcus aureus, the gene product of mprF is responsible for LPG formation. Low pH-inducible genes, termed lpiA, have been identified in the gram-negative α-proteobacteria Rhizobium tropici and Sinorhizobium medicae in screens for acid-sensitive mutants and they encode homologs of MprF. An analysis of the sequenced bacterial genomes reveals that genes coding for homologs of MprF from S. aureus are present in several classes of organisms throughout the bacterial kingdom. In this study, we show that the expression of lpiA from R. tropici in the heterologous hosts Escherichia coli and Sinorhizobium meliloti causes formation of LPG. A wild-type strain of R. tropici forms LPG (about 1% of the total lipids) when the cells are grown in minimal medium at pH 4.5 but not when grown in minimal medium at neutral pH or in complex tryptone yeast (TY) medium at either pH. LPG biosynthesis does not occur when lpiA is deleted and is restored upon complementation of lpiA-deficient mutants with a functional copy of the lpiA gene. When grown in the low-pH medium, lpiA-deficient rhizobial mutants are over four times more susceptible to the cationic peptide polymyxin B than the wild type.

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Common Bean Yield and Zinc Use Efficiency in Association with Diazotrophic Bacteria Co-Inoculations

Agronomy ◽

10.3390/agronomy11050959 ◽

2021 ◽

Vol 11 (5) ◽

pp. 959

Author(s):

Arshad Jalal ◽

Fernando Shintate Galindo ◽

Eduardo Henrique Marcandalli Boleta ◽

Carlos Eduardo da Silva Oliveira ◽

André Rodrigues dos Reis ◽

...

Keyword(s):

Common Bean ◽

Nutrient Use Efficiency ◽

Growth Yield ◽

Staple Food ◽

Human Beings ◽

Rhizobium Tropici ◽

Nutrient Use ◽

Zn Nutrition ◽

Use Efficiency ◽

Soil Zn

Enrichment of staple food with zinc (Zn) along with solubilizing bacteria is a sustainable and practical approach to overcome Zn malnutrition in human beings by improving plant nutrition, nutrient use efficiency, and productivity. Common bean (Phaseolus vulgaris L.) is one of a staple food of global population and has a prospective role in agronomic Zn biofortification. In this context, we evaluated the effect of diazotrophic bacterial co-inoculations (No inoculation, Rhizobium tropici, R. tropici + Azospirillum brasilense, R. tropici + Bacillus subtilis, R. tropici + Pseudomonas fluorescens, R. tropici + A. brasilense + B. subtilis, and R. tropici + A. brasilense + P. fluorescens) in association with soil Zn application (without and with 8 kg Zn ha−1) on Zn nutrition, growth, yield, and Zn use efficiencies in common bean in the 2019 and 2020 crop seasons. Soil Zn application in combination with R. tropici + B. subtilis improved Zn accumulation in shoot and grains with greater shoot dry matter, grain yield, and estimated Zn intake. Zinc use efficiency, recovery, and utilization were also increased with co-inoculation of R. tropici + B. subtilis, whereas agro-physiological efficiency was increased with triple co-inoculation of R. tropici + A. brasilense + P. fluorescens. Therefore, co-inoculation of R. tropici + B. subtilis in association with Zn application is recommended for biofortification and higher Zn use efficiencies in common bean in the tropical savannah of Brazil.

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Enhanced Extracellular Synthesis of Gold Nanoparticles by Soluble Extracts from Escherichia coli Transformed with Rhizobium tropici Phytochelatin Synthase Gene

Metals ◽

10.3390/met11030472 ◽

2021 ◽

Vol 11 (3) ◽

pp. 472

Author(s):

Qunying Yuan ◽

Manjula Bomma ◽

Zhigang Xiao

Keyword(s):

Gold Nanoparticles ◽

Gold Nanoparticle ◽

Synthesis Method ◽

Nanoparticle Synthesis ◽

Morphological Properties ◽

Phytochelatin Synthase ◽

Rhizobium Tropici ◽

Whole Cells ◽

E Coli ◽

Recombinant Cells

Phytochelatins, the enzymatic products of phytochelatin synthase, play a principal role in protecting the plants from heavy metal and metalloid toxicity due to their ability to scavenge metal ions. In the present study, we investigated the capacity of soluble intracellular extracts from E. coli cells expressing R. tropici phytochelatin synthase to synthesize gold nanoparticle. We discovered that the reaction mediated by soluble extracts from the recombinant E. coli cells had a higher yield of gold nanoparticles, compared to that from the control cells. The compositional and morphological properties of the gold nanoparticles synthesized by the intracellular extracts from recombinant cells and control cells were similar. In addition, this extracellular nanoparticle synthesis method produced purer gold nanoparticles, avoiding the isolation of nanoparticles from cellular debris when whole cells are used to synthesize nanoparticles. Our results suggested that phytochelatins can improve the efficiency of gold nanoparticle synthesis mediated by bacterial soluble intracellular extracts, and the potential of extracellular nanoparticle synthesis platform for the production of nanoparticles in large quantity and pure form is worth further investigation.

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P Metabolism in the Bean-Rhizobium tropici Symbiosis

PLANT PHYSIOLOGY ◽

10.1104/pp.113.4.1233 ◽

1997 ◽

Vol 113 (4) ◽

pp. 1233-1242 ◽

Cited By ~ 65

Author(s):

T. S. Al-Niemi ◽

M. L. Kahn ◽

T. R. McDermott

Keyword(s):

Rhizobium Tropici

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Rhizobium tropici Genes Involved in Free-Living Salt Tolerance are Required for the Establishment of Efficient Nitrogen-Fixing Symbiosis with Phaseolus vulgaris

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2002.15.3.225 ◽

2002 ◽

Vol 15 (3) ◽

pp. 225-232 ◽

Cited By ~ 110

Author(s):

Joaquina Nogales ◽

Rosario Campos ◽

Hanaa BenAbdelkhalek ◽

José Olivares ◽

Carmen Lluch ◽

...

Keyword(s):

Salt Tolerance ◽

Phaseolus Vulgaris ◽

Environmental Changes ◽

Nitrogenase Activity ◽

Regulation Of Gene Expression ◽

Elongation Factor ◽

Regulatory System ◽

Trna Synthetase ◽

Nitrogen Fixing ◽

Rhizobium Tropici

Characterization of nine transposon-induced mutants of Rhizobium tropici with decreased salt tolerance (DST) allowed the identification of eight gene loci required for adaptation to high external NaCl. Most of the genes also were involved in adaptation to hyperosmotic media and were required to overcome the toxicity of LiCl. According to their possible functions, genes identified could be classified into three groups. The first group included two genes involved in regulation of gene expression, such as ntrY, the sensor element of the bacterial ntrY/ntrX two-component regulatory system involved in regulation of nitrogen metabolism, and greA, which encodes a transcription elongation factor. The second group included genes related to synthesis, assembly, or maturation of proteins, such as alaS coding for alanine-tRNA synthetase, dnaJ, which encodes a molecular chaperone, and a nifS homolog probably encoding a cysteine desulfurase involved in the maturation of Fe-S proteins. Genes related with cellular build-up and maintenance were in the third group, such as a noeJ-homolog, encoding a mannose-1-phosphate guanylyltransferase likely involved in lipopolysaccharide biosynthesis, and kup, specifying an inner-membrane protein involved in potassium uptake. Another gene was identified that had no homology to known genes but that could be conserved in other rhizobia. When inoculated on Phaseolus vulgaris growing under nonsaline conditions, all DST mutants displayed severe symbiotic defects: ntrY and noeJ mutants were impaired in nodulation, and the remaining mutants formed symbiosis with very reduced nitrogenase activity. The results suggest that bacterial ability to adapt to hyper-osmotic and salt stress is important for the bacteroid nitrogen-fixing function inside the legume nodule and provide genetic evidence supporting the suggestion that rhizobia face severe environmental changes after their release into plant cells.

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Secondary Metabolites of Rhizobium tropici CIAT 899 Added to Bradyrhizobium spp. Inoculant Promote Soybean Growth and Increase Yield

Journal of soil science and plant nutrition ◽

10.1007/s42729-021-00611-z ◽

2021 ◽

Author(s):

Catharine Abreu Bomfim ◽

Lucas Gabriel Ferreira Coelho ◽

Ieda Carvalho Mendes ◽

Helson Mario Martins Vale ◽

Francisco Javier Ollero ◽

...

Keyword(s):

Secondary Metabolites ◽

Rhizobium Tropici ◽

Bradyrhizobium Spp

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Regulation of hsnT, nodF and nodE genes in Rhizobium tropici CIAT 899 and their roles in the synthesis of Nod factors and in the symbiosis

Microbiology ◽

10.1099/mic.0.000824 ◽

2019 ◽

Vol 165 (9) ◽

pp. 990-1000

Author(s):

Douglas Fabiano Gomes ◽

Leandro Datola Tullio ◽

Pablo del Cerro ◽

Andre Shigueyoshi Nakatani ◽

Amanda Alves Paiva Rolla-Santos ◽

...

Keyword(s):

Nod Factors ◽

Rhizobium Tropici

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Inoculante e bioestimulante no desempenho do feijão comum cultivado no ecótono Cerrado-Pantanal

Research Society and Development ◽

10.33448/rsd-v9i5.3380 ◽

2020 ◽

Vol 9 (5) ◽

pp. e188953380

Author(s):

Denise Prevedel Capristo ◽

Francisco Eduardo Torres ◽

Caio Cézar Guedes Corrêa ◽

Flávia Alves da Silva ◽

Angelita dos Santos Zanuncio ◽

...

Keyword(s):

Rhizobium Tropici ◽

Mato Grosso ◽

Mato Grosso Do Sul

O objetivo do estudo foi avaliar o efeito de doses de inoculante e suas interações com bioestimulante no feijão comum. O experimento foi realizado na área experimental da Universidade Estadual de Mato Grosso do Sul, em Aquidauana-MS, utilizando a cultivar TAA Dama do grupo comercial Carioca. O delineamento experimental foi em blocos casualizados, em esquema fatorial 2x5, com quatro repetições. O primeiro fator constitui-se da presença ou ausência de bioestimulante. O segundo fator as doses de inoculante (0 mL, 150 mL, 300 mL, 600 mL, 1200 mL a cada 50 kg de sementes). Foram avaliados o número de nódulos por planta, atividade nodular, matéria verde e seca de nódulos, matéria verde e seca da parte aérea e da raiz, comprimento e densidade da raiz, teor de nitrogênio e fósforo foliar, altura de inserção de primeira vagem, altura de plantas, número de ramificações, número de grãos por vagem, massa de cem grãos e produtividade de grãos. A aplicação do bioestimulante isolado ou em associação com Rhizobium tropici no feijão comum não promove aumento de produtividade de grãos na cultura, ao contrário da prática da inoculação com o referido rizóbio. A dose recomendada do inoculante a base de R. tropici proporciona incrementos na produtividade do feijão comum. O aumento da dose é apenas desperdício.

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COMPONENTES DE RENDIMENTO E PRODUTIVIDADE DO FEIJOEIRO COMUM SUBMETIDO À INOCULAÇÃO E CO-INOCULAÇÃO COM ESTIRPES DE Rhizobium tropici E Azospirillum brasilense

Scientia Agraria ◽

10.5380/rsa.v17i1.47409 ◽

2016 ◽

Vol 17 (1) ◽

Author(s):

João Henrique Schossler ◽

Leandro Meert ◽

Diego Ary Rizzardi ◽

Leandro Michalovicz

Keyword(s):

Azospirillum Brasilense ◽

Rhizobium Tropici

O objetivo do trabalho foi avaliar a influência da inoculação e co-inoculação com bactérias do gênero Rhizobium e Azospirillum sobre os componentes de produção e produtividade do feijoeiro comum. O experimento foi realizado no ano de agrícola de 2015/2016 em delineamento de blocos casualizados com 5 repetições e 4 tratamentos: T1= Testemunha (sem inoculação); T2= Inoculação com Rhizobium tropici; T3= Inoculação com Azospirillum brasilense e T4= Co-inoculação com Rhizobium tropici + Azospirillum brasilense. Os componentes de produção avaliados foram: altura de plantas (cm), diâmetro do colmo (cm), número de vagens por planta, número de grãos por vagem, massa de cem grãos (g) e produtividade (kg ha-1). Os tratamentos com inoculação apresentaram plantas maiores e maior número de vagens por planta do que a testemunha. A inoculação, independente do microrganismo utilizado, aumentou a altura das plantas e o número de vagens por planta. A co-inoculação com Rhizobium tropici + Azospirillum brasilense apresentou a maior massa de cem grãos (25,33 g) e a maior produtividade (2448,45 kg ha-1).

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