Open AccessImproved Eco-Friendly Recombinant Anabaena sp. Strain PCC7120 with Enhanced Nitrogen Biofertilizer Potential
Author(s) -
Akhilesh Kumar Chaurasia,
Shree Kumar Apte
Publication year - 2011
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.01714-10
Subject(s) - strain (injury) , nitrogen fixation , anabaena , biofertilizer , photosynthesis , biology , recombinant dna , nitrogenase , nitrogen , cyanobacteria , botany , microbiology and biotechnology , chemistry , gene , bacteria , biochemistry , genetics , anatomy , organic chemistry
Photosynthetic, nitrogen-fixingAnabaena strains are native to tropical paddy fields and contribute to the carbon and nitrogen economy of such soils. Genetic engineering was employed to improve the nitrogen biofertilizer potential ofAnabaena sp. strain PCC7120. Constitutive enhanced expression of an additional integrated copy of thehetR gene from a light-inducible promoter elevated HetR protein expression and enhanced functional heterocyst frequency in the recombinant strain. The recombinant strain displayed consistently higher nitrogenase activity than the wild-type strain and appeared to be in homeostasis with compatible modulation of photosynthesis and respiration. The enhanced combined nitrogen availability from the recombinant strain positively catered to the nitrogen demand of rice seedlings in short-term hydroponic experiments and supported better growth. The engineered strain is stable, eco-friendly, and useful for environmental application as nitrogen biofertilizer in paddy fields.