Isolation, cloning, and characterization of a partial novel aro A gene in common reed (Phragmites australis)

Abstract

Context: Among the essential amino acids, phenylalanine, tryptophan, and tyrosine are aromatic amino acids which are synthesized by the shikimate pathway in plants and bacteria. Herbicide glyphosate can inhibit the biosynthesis of these amino acids. So, identification of the gene tolerant to glyphosate is very important. It has been shown that the common reed or Phragmites australis Cav. (Poaceae) is relatively tolerant to glyphosate. Objective: The aim of the current research is identification, cloning, sequencing, and registering of partial aro A gene of the common reed P. australis. Materials and methods: The partial aro A gene of common reed (P. australis) was cloned in Escherichia coli and the amino acid sequence was identified/determined for the first time. Results: This is the first report for isolation, cloning, and sequencing of a part of aro A gene from the common reed. A 670 bp fragment including two introns (86 bp and 289 bp) was obtained. The open reading frame (ORF) region in part of gene was encoded for 98 amino acids. Alignment showed high similarity among this region with Zea mays (L.) (Poaceae) (94.6%), Eleusine indica L. Gaertn (Poaceae) (94.2%), and Zoysia japonica Steud. (Poaceae) (94.2%). The alignment of amino acid sequence of the investigated part of the gene showed a homology with aro A from several other plants. This conserved region forms the enzyme active site. Conclusion: The alignment results of nucleotide and amino acid residues with related sequences showed that there are some differences among them. The relative glyphosate tolerance in the common reed may be related to these differences.