Production of agrocinopine A by Ipomoea batatas agrocinopine synthase in transgenic tobacco and its effect on the rhizosphere microbial community

Agrobacterium tumefaciens is a bacterial pathogen that causes crown gall disease on a wide range of eudicot plants by genetic transformation. Besides T-DNA integrated by natural transformation in vegetative tissues of plants by pathogenic Agrobacterium, previous reports have indicated that T-DNA sequences originating from ancestral Agrobacterium sp. are present in the genomes of all cultivated sweet potato (Ipomoea batatas) analyzed. Expression of Agrobacterium-derived agrocinopine synthase (ACS) gene was detected in leaf and root tissues of sweet potato, suggesting that the plant can produce agrocinopine, a sugar-phosphodiester opine considered to be utilized by Agrobacterium in crown gall. To validate the product synthesized by I. batatas ACS (IbACS), we introduced IbACS into tobacco under a constitutive promoter. High voltage paper electrophoresis followed by alkaline silver nitrate staining detected the production of an agrocinopine-like substance in IbACS1-expressing tobacco, and further MS and NMR analyses of the product confirmed that IbACS can produce agrocinopine A from natural plant substrates. The partially purified compound was biologically active in an agrocinopine A bioassay. 16S rRNA amplicon sequencing and meta-transcriptome analysis revealed that the rhizosphere microbial community of tobacco was affected by the expression of IbACS. A new species of Leifsonia (actinobacteria) was isolated as an enriched bacterium in the rhizosphere of IbACS1-expressing tobacco. This Leifsonia sp. can catabolize agrocinopine A produced in tobacco, indicating that the production of agrocinopine A attracts rhizosphere bacteria which can utilize this sugar-phosphodiester. These results suggest a potential role of IbACS conserved among sweet potato cultivars in manipulating their microbial community.

On-chip Paper Electrophoresis for Ultrafast Screening of Infectious Diseases

The outbreak of new viral strains promotes advances in universal diagnostic techniques for detecting infectious diseases with unknown viral sequence. Long double-stranded RNA (dsRNA), a hallmark of infections, serves as a virus marker for prompt detection of viruses with unknown genomes. Here, we report on-chip paper electrophoresis for ultrafast screening of infectious diseases. Negatively charged RNAs pass through the micro and nanoscale pores of cellulose in order of size under an external electric field applied to the paper microfluidic channel. Quantitative separation of long dsRNA mimicking poly I:C was analyzed from 1.67 to 33 ng·μL−1, which is close to the viral dsRNA concentration in infected cells. This paper-based capillary electrophoresis chip (paper CE chip) can provide a new diagnostic platform for ultrafast viral disease detection at the point-of-care (POC) level.

Radioiodination and biological evaluation of landiolol as a tracer for myocardial perfusion imaging: preclinical evaluation and diagnostic nuclear imaging

The present work has assessed the ability and competency of radioiodinated landiolol that is considered a potential cardio selective imaging agent. Landiolol was radiosynthesized with [131I] using chloramine-T (Ch-T) as an oxidizing agent. To give high radiochemical yield of the [131I]landiolol reaching values of 98% with high stability up to 48 h. The labeled compound was separated and purified using thin layer chromatography (TLC), paper electrophoresis and high performance liquid chromatography (HPLC). Biodistribution studies indicated that [131I]landiolol gave high heart uptake ratio of [45.0±0.19% ID/g at 2 min post injection (p.i.)]. Therefore, [131I]landiolol could be considered as a novel tracer to image heart with high heart/blood ratio within 60 min.

Radioiodination of olmesartan medoxomil and biological evaluation of the product as a tracer for cardiac imaging

The present study is oriented to synthesis of radioiodinated olmesartan medoxomil (OM) for potential cardiac imaging. Olmesartan medoxomil has been labeled with [125/131I] using chloramine-T (Ch-T) as an oxidizing agent. The key effective factors such as amount of oxidizing agent, amount of substrate, pH, reaction temperature and reaction time, have been systematically studied to get high radiochemical yield of the [125I]olmesartan medoxomil reaching values of 98.5%. The labeled compound was separated and purified using thin layer chromatography (TLC), paper electrophoresis and high performance liquid chromatography (HPLC). The biological distribution indicates the suitability of [125I]olmesartan medoxomil as a novel tracer to image heart with high heart/blood ratio within 30 min which was detected by gamma camera.

Genetic variation of the japanese quail (Coturnix Coturnix Japonica) based on biochemical polymorphism

The study aimed at characterizing the Japanese quail using biochemical markers. Blood protein polymorphism of one hundred and sixty-six (166) Japanese quails of both sexes comprising of 83 each of mottled brown and white quails were analysed using cellulose acetate paper electrophoresis. Six loci which includes hemoglobin (Hb), transferrin (Tf), albumin (Alb), carbonic anhydrase (CA), alkaline phosphatase (Alp) and esterase-1 (Es-1) were tested. All the loci tested were polymorphic with each locus having two co-dominant alleles controlling three genotypes. Allele B was predominant at Hb, Tf and Es-1 locus with frequencies 0.90, 0.55, and 0.77, respectively while Allele A was predominant at Alb and Alp locus with frequencies 0.83 and 0.58 respectively. The Allele A had generally lower frequencies than B at the CA loci having values of 0.43 - Brown, 0.38 - White and 0.40 - overall. The mean observed heterozygosity (Ho) was 0.48 with brown and white quails having Ho values of 0.47 and 0.49 respectively, and the expected heterozygosity was observed to be higher in white quails (0.39) than in the mottled brown (0.31). The genetic distance (0.0534) between white and brown quails in this study showed little genetic differentiation between the brown and the white quails. Dendogram generated from the genetic distance values indicated that the two strains had common origin.

A fully disposable paper-based electrophoresis microchip with integrated pencil-drawn electrodes for contactless conductivity detection

We describe the development of a paper electrophoresis chip integrated with pencil electrodes for contactless conductivity detection and its application in the separation of biomolecules associated with kidney dysfunctions.