LEAF-NODULE SYMBIOSIS. I. ENDOPHYTE OF PSYCHOTRIA BACTERIOPHILA
Journal of Bacteriology
|September 1, 1964
Summary
The leaf-nodule endophyte of Psychotria bacteriophila, identified as Klebsiella rubiacearum, efficiently fixes nitrogen (N2) under anaerobic conditions. This process is linked to pyruvate and hydrogen metabolism in pure cultures.
Area of Science:
- Microbiology
- Plant Science
- Biochemistry
Background:
- Leaf nodules in *Psychotria bacteriophila* harbor a symbiotic endophyte.
- Understanding the identity and function of this endophyte is crucial for plant-microbe interactions.
Purpose of the Study:
- To isolate and identify the leaf-nodule endophyte of *Psychotria bacteriophila*.
- To investigate the nitrogen-fixing capabilities of the isolated endophyte.
Main Methods:
- Isolation of the endophyte from seedlings and leaves on nitrogen-free agar.
- Characterization using morphological, serological, and cultural methods.
- Assessing nitrogen fixation (N2) efficiency in pure cultures under anaerobic conditions.
Main Results:
- The endophyte was successfully isolated and identified as belonging to the *Klebsiella-Aerobacter* group, provisionally named *Klebsiella rubiacearum*.
- Pure cultures demonstrated efficient nitrogen fixation (4.54 µg N fixed/mg glucose) under anaerobic conditions.
- Nitrogen fixation was found to be closely associated with pyruvate and hydrogen metabolism.
Conclusions:
- The leaf-nodule endophyte of *Psychotria bacteriophila* is *Klebsiella rubiacearum*.
- *Klebsiella rubiacearum* is capable of significant nitrogen fixation.
- Pyruvate and hydrogen metabolism are key factors in the nitrogen fixation process of this endophyte.
Keywords:
CARBOHYDRATE METABOLISMCOLORIMETRYEXPERIMENTAL LAB STUDYHYDROGENKLEBSIELLAMETABOLISMNITROGEN FIXATIONPHOTOMICROGRAPHYPYRUVATESSYMBIOSISTREESMore Related Videos
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