BACKGROUND The chloroplast trnH-psbA spacer region has been proposed as a prime candidate for use in DNA barcoding of plants because of its high substitution rate. However, frequent inversions associated with palindromic sequences within this region have been found in multiple lineages of Angiosperms and may complicate its use as a barcode, especially if they occur within species. METHODOLOGY...

To construct a DNA-linked RNase H, which cleaves RNA site-specifically at high temperatures, the 15-mer DNA, which is complementary to the polypurine-tract sequence of human immunodeficiency virus-1 RNA (PPT-RNA), was cross-linked to the unique thiol group of Cys135 in the Thermus thermophilus RNase HI variant. The resultant DNA-linked enzyme (d15-C135/TRNH), as well as the d15-C135/ERNH, in wh...

The rbcL (ribulose-1,5-biphosphate carboxylase oxygenase) gene plays a crucial role in carbon fixation. Previous studies shed light on its evolutionary relationship among different Phyla. Here, authors have done a comparative study of rbcL genes among proteobacteria, archaea, cyanobacteria and plants based on their compositional variations (GC%, amino acid frequency, codon usage, etc.). In addi...

DNA barcoding of United Arab Emirates (UAE) native plants is of high practical and scientific value as the plants adapt to very harsh environmental conditions that challenge their identification. Fifty-one plant species belonged to 22 families, 2 monocots, and 20 eudicots; a maximum number of species being legumes and grasses were collected. To authenticate the morphological identification of t...

The carboxylation of ribulose biphosphate by the enzyme ribulosebisphosphate carboxylase/oxygenase is the mechanism for CO2 fixation and primary production in nearly all ecosystems on this planet. Although certain algal isolates and higher plants contain conserved nucleotide sequences in the large subunit of the gene (rbcL) for this enzyme, such genes from natural microbial assemblages have not...

Targeted gene replacement in plastids was used to explore whether the rbcL gene that codes for the large subunit of ribulose-1, 5-bisphosphate carboxylase/oxygenase, the key enzyme of photosynthetic CO2 fixation, might be replaced with altered forms of the gene. Tobacco (Nicotiana tabacum) plants were transformed with plastid DNA that contained the rbcL gene from either sunflower (Helianthus an...

Land plants have had the reputation of being problematic for DNA barcoding for two general reasons: (i) the standard DNA regions used in algae, animals and fungi have exceedingly low levels of variability and (ii) the typically used land plant plastid phylogenetic markers (e.g. rbcL, trnL-F, etc.) appear to have too little variation. However, no one has assessed how well current phylogenetic re...

Small regulatory RNAs (sRNAs) function as transcriptional and post-transcriptional regulators of gene expression in organisms from all domains of life. Cyanobacteria are thought to have developed a complex RNA-based regulatory mechanism. In the current study, by genome-wide analysis of differentially expressed small RNAs in Synechocystis sp. PCC 6803 under high light conditions, we discovered a...