Sinorhizobium meliloti

From MicrobeWiki, the student-edited microbiology resource

A Microbial Biorealm page on the genus Sinorhizobium meliloti

Classification

Higher order taxa

Bacteria; Proteobacteria; Alphaproteobacteria; Rhizobiales; Rhizobiazeae; Sinorhizobium


[Others may be used. Use NCBI link to find]

Species

NCBI: Taxonomy

Sinorhizobium meliloti;

Description and significance

Sinorhizobium meliloti is a gram-negative bacterium. As are other Rhizobia, S. meliloti can be found as a normal, free-living microorganisms in the soil. However, it is for their nitrogen-fixing symbiotic relationships with legumes that S. meliloti are studied. S. meliloti cells detect substances particularly made up of amino and organic acids, released by the roots of plants. The cells are drawn toward root hairs that emerge from the roots and induce the root hair tips to curl up. There is a cytoplasmic bridge formed by the microtubules and the cytoplasm of the root cells. This bridge guides infection threads extending from the roots to the cortex of the bacterial cells. Finally, the S. meliloti cells enter the cytoplasm of the root cells through endocytosis. S. meliloti transform atmospheric nitrogen into a form that may be utilized by the host in which they reside. Also, the S. meliloti is significant in that it leaves behind excess nitrogen in the soil which may potentially reduce the need for fertilizers.


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Genome structure

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Cell structure and metabolism

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Ecology

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Pathology

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Application to Biotechnology

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Current Research

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References

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

Edited by student of Rachel Larsen