Biomaterial Database

Root exudates in relation to growth and nitrogenase activity of Rhizobium japonicum. 1981

S A Odunfa, and D Werner

Root exudates of cowpea and soybean were collected in aerated water cultures. The ability of these exudates to support nitrogenase activity of R. japonicum was studied on defined media. When a complete nitrogenase-inducing medium was supplemented with concentrated root exudate, there was an increased nitrogenase activity. When the cowpea root exudate was substituted for glutamine or sodium succinate in the medium, nitrogenase activity was not detected. Growth was good when the root exudate was substituted for sodium succinate but was poor when the exudate replaced glutamine. There was nitrogenase activity in R. japonicum when the cowpea root exudate was substituted for arabinose in the 20E medium. Gas chromatographic analyses of cowpea root exudates revealed that ribose, arabinose, glucose, and sucrose were the main constituents. The significance of this finding in the asymbiotic nitrogen fixation by Rhizobium spp. is discussed.

UI	MeSH Term	Description	Entries
D007887	Fabaceae	The large family of plants characterized by pods. Some are edible and some cause LATHYRISM or FAVISM and other forms of poisoning. Other species yield useful materials like gums from ACACIA and various LECTINS like PHYTOHEMAGGLUTININS from PHASEOLUS. Many of them harbor NITROGEN FIXATION bacteria on their roots. Many but not all species of "beans" belong to this family.	Afzelia,Amorpha,Andira,Baptisia,Callerya,Ceratonia,Clathrotropis,Colophospermum,Copaifera,Delonix,Euchresta,Guibourtia,Legumes,Machaerium,Pithecolobium,Stryphnodendron,Leguminosae,Pea Family,Pithecellobium,Tachigalia,Families, Pea,Family, Pea,Legume,Pea Families
D009591	Nitrogenase	An enzyme system that catalyzes the fixing of nitrogen in soil bacteria and blue-green algae (CYANOBACTERIA). EC 1.18.6.1.	Dinitrogenase,Vanadium Nitrogenase,Nitrogenase, Vanadium
D010946	Plants, Medicinal	Plants whose roots, leaves, seeds, bark, or other constituent parts possess therapeutic, tonic, purgative, curative or other pharmacologic attributes, when administered to man or animals.	Herbs, Medicinal,Medicinal Herbs,Healing Plants,Medicinal Plants,Pharmaceutical Plants,Healing Plant,Herb, Medicinal,Medicinal Herb,Medicinal Plant,Pharmaceutical Plant,Plant, Healing,Plant, Medicinal,Plant, Pharmaceutical,Plants, Healing,Plants, Pharmaceutical
D003470	Culture Media	Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.	Media, Culture
D005973	Glutamine	A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.	D-Glutamine,L-Glutamine,D Glutamine,L Glutamine
D001089	Arabinose		L-Arabinose,L Arabinose
D012231	Rhizobium	A genus of gram-negative, aerobic, rod-shaped bacteria that activate PLANT ROOT NODULATION in leguminous plants. Members of this genus are nitrogen-fixing and common soil inhabitants.
D013386	Succinates	Derivatives of SUCCINIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a 1,4-carboxy terminated aliphatic structure.	Succinic Acids,Acids, Succinic
D019802	Succinic Acid	A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawley's Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851)	Potassium Succinate,Succinate,1,2-Ethanedicarboxylic Acid,1,4-Butanedioic Acid,Ammonium Succinate,Butanedioic Acid,1,2 Ethanedicarboxylic Acid,1,4 Butanedioic Acid,Succinate, Ammonium,Succinate, Potassium