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. 1984 Mar;81(5):1566-9.
doi: 10.1073/pnas.81.5.1566.

Rhizobium free-living nitrogen fixation occurs in specialized nongrowing cells

R A Ludwig  1
Affiliations

Rhizobium free-living nitrogen fixation occurs in specialized nongrowing cells

R A Ludwig. Proc Natl Acad Sci U S A. 1984 Mar.

Abstract

A model for free-living N(2) fixation by Rhizobium sp. RC3200 is presented that asserts that this process occurs in nongrowing cells. Cultures containing mixed populations of cell types, N(2)-fixing and vegetative, grow cooperatively. In nitrogen-limited liquid suspension cultures, cooperative growth occurs by means of ammonium that is produced and exported by nongrowing, N(2)-fixing cells and transported to vegetative cells. This model implies prokaryotic differentiation: the creation of metabolically specialized cells, terminally nonviable, that functionally cooperate in a higher cell order. Here, the switch to a Rhizobium N(2)-fixing cell state is regulated by both O(2) and utilizable nitrogen.

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References

    1. Proc Natl Acad Sci U S A. 1980 Oct;77(10):5817-21 - PubMed
    1. J Bacteriol. 1980 Mar;141(3):1209-16 - PubMed
    1. J Bacteriol. 1983 Mar;153(3):1196-201 - PubMed
    1. Anal Biochem. 1980 Sep 15;107(2):337-40 - PubMed
    1. Anal Biochem. 1977 May 1;79(1-2):544-52 - PubMed

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