Isolation and characterization of Rhizobium etli mutants altered in degradation of asparagine.

نویسندگان

  • A Huerta-Zepeda
  • L Ortuño
  • G Du Pont
  • S Durán
  • A Lloret
  • H Merchant-Larios
  • J Calderón
چکیده

Rhizobium etli mutants unable to grow on asparagine as the nitrogen and carbon source were isolated. Two kinds of mutants were obtained: AHZ1, with very low levels of aspartase activity, and AHZ7, with low levels of asparaginase and very low levels of aspartase compared to the wild-type strain. R. etli had two asparaginases differentiated by their thermostabilities, electrophoretic mobilities, and modes of regulation. The AHZ mutants nodulated as did the wild-type strain and had nitrogenase levels similar to that of the wild-type strain.

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عنوان ژورنال:
  • Journal of bacteriology

دوره 179 6  شماره 

صفحات  -

تاریخ انتشار 1997