Genomic Analysis of Nitrogen Fixation

  • Ina P. O’Carroll
  • Patricia C. Dos SantosEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 766)


Advances in sequencing technology in the past decade have enabled the sequencing of genomes of thousands of organisms including diazotrophs. Genomics have enabled thorough analysis of the gene organization of nitrogen-fixing species, the identification of new genes involved in nitrogen fixation, and the identification of new diazotrophic species. This chapter reviews key characteristics of nitrogen-fixing genomes and methods to identify and analyze genomes of new diazotrophs using genome scanning. This chapter refers to Azotobacter vinelandii, a well-studied nitrogen-fixing organism, as a model for studying nitrogen-fixing genomes. We discuss the main nitrogen fixation genes as well as accessory genes that contribute to diazotrophy. We also review approaches that can be used to modify genomes in order to study nitrogen fixation at the genetic, biochemical, and biophysical level.

Key words

Genome sequencing genome scanning genomics Azotobacter vinelandii nitrogen fixation 


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© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.HIV Drug Resistance ProgramNational Cancer Institute at FrederickFrederickUSA
  2. 2.Department of ChemistryWake Forest UniversityWiston-SalemUSA

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