nifH gene Study of Mesorhizobium ciceri isolated From Iran

Subject Areas : Molecular Microbiology

Elham  Moazemian ¹ (Department of microbiology, Islamic Azad University, Science & Research, Fars Branch, Fars, Iran)
Mohammad  Kargar ² (Department of Microbiology, Islamic Azad University, Jahrom Branch, Jahrom, Iran)
Ahmad  Asgharzadeh ³ (Water & Soil Research Institute, Iran)
Sayed Mehdi  Hoseini Mazinani ⁴ (National Institute for Genetic Engineering and Biotechnology, Iran)

Received: 2009-04-14 Accepted : 2009-05-15 Published : 2009-04-01

Keywords: Mesorhizobium ciceri, nifHDK operon, nitrogen fixation, Cicer arietinum,

Abstract :

Background and objectives: Cicer arietinum is the world`s third ranking and Iran`s first ranking legume in terms of amount of production. Mesorhizobium ciceri is the most important bacteria that has symbiosis with this plant and fixes nitrogen for this legume. The symbiotic Rhizobium of this plant are quite effective in fixing nitrogen molecule. Therefore the study of this phenomenon is great important. Atmospheric nitrogen fixation requires nitrogenase enzyme. nifH, nifD and nifK genes encode three polypeptides of the nitrogenase complex.      Material and methods: After isolation of bacteria and culture, total DNA was isolated by using a standard protocol and it was used as template. The nifH gene was amplified from genomic DNA by PCR method with appropriate primers.     Results:   Using two sets of primers nifH1/nifH2 and nifH4/nifD1, amplified products of the expected size were obtained on DNA extracted from M. ciceri. The amplified products obtained with the nifH gene was purified and sequenced. The nucleotide sequences of nifH gene of M.ciceri was performed.     Conclusion: It shown 90% homology with the nifH gene in M.loti. This gene has also shown high homology with nifH gene in other Rhizobium species.