Whole-Genome Characterization of Alfalfa Mosaic Virus Obtained from Metagenomic Analysis of Vinca minor and Wisteria sinensis in Iran: with Implications for the Genetic Structure of the Virus

Alfalfa mosaic virus (AMV), an economically important pathogen, is present worldwide with a very wide host range. This work reports for the first time the infection of Vinca minor and Wisteria sinensis with AMV using RNA sequencing and reverse transcription polymerase chain reaction confirmation. De novo assembly and annotating of contigs revealed that RNA1, RNA2, and RNA3 genomic fragments consist of 3,690, 2,636, and 2,057 nucleotides (nt) for IR-VM and 3,690, 2,594, and 2,057 nt for IR-WS. RNA1 and RNA3 segments of IR-VM and IR-WS closely resembled those of the Chinese isolate HZ, with 99.23-99.26% and 98.04-98.09% nt identity, respectively. Their RNA2 resembled that of Canadian isolate CaM and American isolate OH-2-2017, with 97.96-98.07% nt identity. The P2 gene revealed more nucleotide diversity compared with other genes. Genes in the AMV genome were under dominant negative selection during evolution, and the P1 and coat protein (CP) proteins were subject to the strongest and weakest purifying selection, respectively. In the population genetic analysis based on the CP gene sequences, all 107 AMV isolates fell into two main clades (A, B) and isolates of clade A were further divided into three groups with significant subpopulation differentiation. The results indicated moderate genetic variation within and no clear geographic or genetic structure between the studied populations, implying moderate gene flow can play an important role in differentiation and distribution of genetic diversity among populations. Several factors have shaped the genetic structure and diversity of AMV: selection, recombination/reassortment, gene flow, and random processes such as founder effects.

Study of Antimicrobial Activity of Vegetable Alcoholic Extracts Obtained from Vinca Minor L.

Important natural antimicrobial compounds derived from Vinca minor L. plant contain a wide variety of secondary metabolites which are useful for brain health (increasing blood circulation in the brain, supporting brain metabolism, preventing memory loss and problems with concentration and premature aging of the cell), and externally they play a role in tissue repair and skin lesion healing. The testing of the antimicrobial activity of the alcoholic plant extracts obtained from Vinca minor plant was performed on two types of pathogenic germs: a Gram-positive strain, Staphylococcus aureus ATCC 25923 and a Gram-negative strain, Escherichia Coli ATCC 25922, as well as on a yeast strain pathogenic, Candida albicans ATCC 900288. Quantitative evaluation of antimicrobial activity was performed by a variant of the Kirby-Bauer diffusimetric method, a simple and fast method that allows the determination of the spectrum of sensitivity / resistance to antibiotics of the microorganism. Experimental studies have shown that all samples of alcoholic extract of 70 percent concentration, in volumes of 7µL, exerted a total antibacterial inhibitory action against the reference strains E. coli ATCC 25922 and C. albicans ATCC 10231 and moderate against the strain S. aureus ATCC 25923, results that agree with the literature. Regarding the alcoholic plant extracts with a concentration of 40 percent ethyl alcohol, obtained from the leaf and stem of Vinca minor plant, they did not show antimicrobial activity, which suggests that 40 percent ethyl alcohol does not extract bioactive compounds with antimicrobial activity.

Symbol der Unsterblichkeit

SummaryVinca minor L., das kleine Immergrün, ist Trostspender am Grab und Heilpflanze in der Homöopathie und Spagyrik.

Spectrophotometric Studies of Indolic Compounds from Vinca Minor L.

The most medically representative plant in the Apocynaceae family is Vinca minor. Vinca minor is a perennial, herbaceous plant, commonly known as Saschiu. In the present research we aimed to isolate the indole compounds from Vinca minor L. and to carry out some physico-chemical studies on these compounds: UV-VIS spectroscopy and the determination of the polyphenols content using Folin-Ciocâlteu method. The spectrophotometric study of the alcoholic plant extracts obtained from the leaf and stem of Vinca minor was performed using the UV-VIS spectrophotometric method and a VWR UV-630PC double beam spectrophotometer. Both samples of plant alcoholic extracts obtained from the leaf and from the stem of Vinca minor L. had the specific absorption maxima detected in the range 225-350 nm and the absorbance maximum in both cases was 3.5 (u.a- absorbency units). The total content of polyphenols was determined by the Folin-Ciocâlteu method from alcoholic extracts of different concentrations: 40 percent, 70 percent, 96 percent (T40, T70, T96, F40, F70, F96) obtained from the leaf and stem of Vinca minor plant using the spectrophotometer model JASCO- 550 UV VIS. Regarding the alcoholic extracts obtained from the leaf of Vinca minor L., the concentrations of polyphenols were between 812.50 mg / 100g pv and 1737.50 mg / 100g pv and and in the case of alcoholic extracts obtained from the strain, the results were between 1525.00-3962.50 mg GAE / 100 g pv, results that were in accordance with the literature.

Identifying Genes Involved in Alkaloid Biosynthesis in Vinca minor through Transcriptomics and Gene Co-Expression Analysis

The lesser periwinkle Vinca minor accumulates numerous monoterpene indole alkaloids (MIAs) including the vasodilator vincamine. While the biosynthetic pathway of MIAs has been largely elucidated in other Apocynaceae such as Catharanthus roseus, the counterpart in V. minor remains mostly unknown, especially for reactions leading to MIAs specific to this plant. As a consequence, we generated a comprehensive V. minor transcriptome elaborated from eight distinct samples including roots, old and young leaves exposed to low or high light exposure conditions. This optimized resource exhibits an improved completeness compared to already published ones. Through homology-based searches using C. roseus genes as bait, we predicted candidate genes for all common steps of the MIA pathway as illustrated by the cloning of a tabersonine/vincadifformine 16-O-methyltransferase (Vm16OMT) isoform. The functional validation of this enzyme revealed its capacity of methylating 16-hydroxylated derivatives of tabersonine, vincadifformine and lochnericine with a Km 0.94 ± 0.06 µM for 16-hydroxytabersonine. Furthermore, by combining expression of fusions with yellow fluorescent proteins and interaction assays, we established that Vm16OMT is located in the cytosol and forms homodimers. Finally, a gene co-expression network was performed to identify candidate genes of the missing V. minor biosynthetic steps to guide MIA pathway elucidation.