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. 1978 Jun;61(6):980–983. doi: 10.1104/pp.61.6.980

Initial Organic Products of Fixation of [13N]Dinitrogen by Root Nodules of Soybean (Glycine max) 1

John C Meeks 1,2,3,2, C Peter Wolk 1,2,3,3, Norbert Schilling 1,2,3, Paul W Shaffer 1,2,3, Yael Avissar 1,2,3, Wan-Shen Chien 1,2,3
PMCID: PMC1092024  PMID: 16660438

Abstract

When detached soybean Glycine max (L.) Merr. cv. Hark, nodules assimilate [13N]N2, the initial organic product of fixation is glutamine; glutamate becomes more highly radioactive than glutamine within 1 minute; 13N in alanine becoms detectable at 1 minute of fixation and increases rapidly between 1 and 2 minutes. After 15 minutes of fixation, the major 13N-labeled organic products in both detached and attached nodules are glutamate and alanine, plus, in the case of attached nodules, an unidentified substance, whereas [13N]glutamine comprises only a small fraction of organic 13N, and very little 13N is detected in asparagine. The fixation of [13N]N2 into organic products was inhibited more than 99% by C2H2 (10%, v/v). The results support the idea that the glutamine synthetase-glutamate synthase pathway is the primary route for assimilation of fixed nitrogen in soybean nodules.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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