nifH

“Candidatus Macondimonas diazotrophica”, a novel gammaproteobacterial genus dominating crude-oil-contaminated coastal sediments

Modeling crude-oil biodegradation in sediments remains a challenge due in part to the lack of appropriate model organisms. Here we report the metagenome-guided isolation of a novel organism that represents a phylogenetically narrow (97% 16S rRNA gene …

Diazotroph community characterization via a highthroughput nifH amplicon sequencing and analysis pipeline

The dinitrogenase reductase gene (nifH) is the most widely established molecular marker for the study of nitrogen-fixing prokaryotes in nature. A large number of PCR primer sets have been developed for nifH amplification, and the effective deployment …

The Use of Degenerate Primers in qPCR Analysis of Functional Genes Can Cause Dramatic Quantification Bias as Revealed by Investigation of nifH Primer Performance

The measurement of functional gene abundance in diverse microbial communities often employs quantitative PCR (qPCR) with highly degenerate oligonucleotide primers. While degenerate PCR primers have been demonstrated to cause template-specific bias in …

Assessment of Nitrogenase Diversity in the Environment

Diazotrophic microorganisms are taxonomically and metabolically diverse and they populate a wide variety of habitats. Diazotroph diversity is typically quantified through the analysis of nitrogenase nifH gene sequences recovered from environmental …

A comprehensive aligned nifH gene database: A multipurpose tool for studies of nitrogen-fixing bacteria

We describe a nitrogenase gene sequence database that facilitates analysis of the evolution and ecology of nitrogen-fixing organisms. The database contains 32 954 aligned nitrogenase nifH sequences linked to phylogenetic trees and associated sequence …

A comprehensive evaluation of PCR primers to amplify the nifH gene of nitrogenase

The nifH gene is the most widely sequenced marker gene used to identify nitrogen-fixing Bacteria and Archaea. Numerous PCR primers have been designed to amplify nifH, but a comprehensive evaluation of nifH PCR primers has not been performed. We …

A global census of nitrogenase diversity

The global diversity of nitrogen-fixing microorganisms was assessed through construction and analysis of an aligned database of 16,989 nifH sequences. We conclude that the diversity of diazotrophs is still poorly described and that many organisms …