title: Phylogeny and evolutionary genetics of Frankia strains based on 16S rRNA and nifD-K gene sequences.
abstract: 16S rRNA and nifD-nifK sequences were used to study the molecular phylogeny and evolutionary genetics of Frankia strains isolated from Hippöphae salicifolia D. Don growing at different altitudes (ecologically classified as riverside and hillside isolates) of the Eastern Himalayan region of North Sikkim, India. Genetic information for the small subunit rRNA (16S rRNA) revealed that the riverside Frankia isolates markedly differed from the hillside isolates suggesting that the riverside isolates are genetically compact. Further, for enhanced resolutions, the partial sequence of nifD (3' end), nifK (5' end) and nifD-K IGS region have been investigated. The sequences obtained, failed to separate riverside isolates and hillside isolates, thus suggesting a possible role of genetic transfer events either from hillside to riverside or vice versa. The evolutionary genetic analyses using evogenomic extrapolations of gene sequence data obtained from 16S rRNA and nifD-K provided differing equations with the pace of evolution being more appropriately, intermediate. Values of recombination frequency (R), nucleotide diversity per site (Pi), and DNA divergence estimates supported the existence of an intermixed zone where spatial isolations occurred in sync with the temporal estimates. J. Basic Microbiol. 2015, 54, 1-9.
authors: Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India.
authors: Arun Kumar
authors: AK
authors: Mishra
authors: Department of Botany, Banaras Hindu University, Varanasi, India.
authors: Pawan Kumar
authors: PK
authors: Singh
authors: Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India.|Microbial Culture Collection (MCC), National Centre for Cell Science (NCCS), Pune, India.
authors: Prashant
authors: P
authors: Singh
authors: Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India.
authors: Anumeha
authors: A
authors: Singh
authors: Department of Botany, GGV, Bilaspur, Chhattisgarh, India.
authors: Satya Shila
authors: SS
authors: Singh
authors: Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India.
authors: Amrita
authors: A
authors: Srivastava
authors: National Bureau of Agriculturally Important Microorganisms, Maunath Bhanjan, India.
authors: Alok Kumar
authors: AK
authors: Srivastava
authors: Department of Biotechnology, Gauhati University, Guwahati, Assam, India.
authors: Hridip Kumar
authors: HK
authors: Sarma
mesh_terms: D021901:DNA, Intergenic; D019143:Evolution, Molecular; D040161:Frankia / Q000145:classification / Q000235:genetics* / Q000254:growth & development; D005798:Genes, Bacterial; D020459:Genes, rRNA; D031281:Hippophae / Q000382:microbiology; D007194:India; D009591:Nitrogenase / Q000235:genetics; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D053204:Root Nodules, Plant / Q000382:microbiology; D017422:Sequence Analysis, DNA
chemical_list: D021901:DNA, Intergenic; D012336:RNA, Ribosomal, 16S; D009591:Nitrogenase
keywords: 16S rRNA gene sequences; Frankia; nifD-K IGS sequences and evolutionary genetics