Ecology and physiology of non-Frankia actinobacteria from actinorhizal plants


Actinorhizal plants are well-known for their symbiotic association with the actinobacteria Frankia. However, little is known about their association with other diverse non-Frankia actinobacteria. These bacteria are found within same microniche as Frankia, and have attracted interest in regard to their ecophysiological roles in these environments. Most of these actinobacteria isolated from actinorhizal plants are classified as members of the Streptomyces, Micromonospora, Nocardia, and Actinoplanes genera. Analysis of the physiological properties of these actinobacteria demonstrated their metabolic versatility including biosynthetic potential to produce phytohormones and antimicrobials, and their capacity to act as “helper” bacteria to facilitate plant nodulation. Three genomes from these non-Frankia actinobacteria have been sequenced. Initial analysis of the first two genome sequences available indicates differences in their genome plasticity and genetic content reflecting genome stability variation between the two genomes.

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Journal Title

Plasticity in Plant-Growth-Promoting and Phytopathogenic Bacteria



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Document Type

Book Chapter


© Springer Science+Business Media New York 2014