Dataset Information

A Simplified Protocol for Reversing Phenotypic Conversion of Ralstonia solanacearum during Experimentation.

ABSTRACT:

Background

Ralstonia solanacearum has the problem of losing the virulence in laboratory conditions, during prolonged experimentation. Since pure colonies of R. solanacearum contain cell fractions differing in virulence, it was considered worthwhile to find a way of selecting the cells with lower attenuation. Therefore, a methodology for inducing virulent-type colonies occurrence in Ralstonia solanacearum was developed.

Methods

Nutrient gradient was created by swabbing R. solanacearum culture in a slanted KMTTC medium, and Phyllanthus emblica extract was given by well diffusion. Live-dead cell imaging using BacLight, effects of ascorbic acid on cell viability, and production of virulence factors (exopolysaccharides, cellulase, and pectinase) supported this hypothesis. The tagging of R. solanacearum with green fluorescent protein and further confocal scanning laser microscopic visualization confirmed the colonization in vascular bundles of tomato.

Results

P. emblica extract suppressed R. solanacearum initially in well diffusion, but further developed virulent-type colonies around the wells. Nutrient deprivation was found to have synergistic effects with P. emblica extract. The converted fluidal (virulent type) colonies could be able to colonize vascular bundles and cause wilting symptoms.

Conclusion

This method will be useful in the laboratories working on biocontrol of R. solanacearum for maintaining virulent-type colonies. Moreover, it could form the basis for studies on the stability of phenotypic conversion and cell fractions in R. solanacearum.

SUBMITTER: Sahu PK

PROVIDER: S-EPMC7344456 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Publications

A Simplified Protocol for Reversing Phenotypic Conversion of <i>Ralstonia solanacearum</i> during Experimentation.

Sahu Pramod Kumar PK Singh Shailendra S Gupta Amrita A Singh Udai B UB Paul Surinder S Paul Diby D Kuppusamy Pandiyan P Singh Harsh V HV Saxena Anil Kumar AK

International journal of environmental research and public health 20200615 12

<h4>Background</h4><i>Ralstonia solanacearum</i> has the problem of losing the virulence in laboratory conditions, during prolonged experimentation. Since pure colonies of <i>R. solanacearum</i> contain cell fractions differing in virulence, it was considered worthwhile to find a way of selecting the cells with lower attenuation. Therefore, a methodology for inducing virulent-type colonies occurrence in <i>Ralstonia solanacearum</i> was developed.<h4>Methods</h4>Nutrient gradient was created by ...[more]

PMID: 32549351

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