Incidence and genetic diversity of raspberry bushy dwarf virus (RBDV) in Rubus spp. in Turkey

Raspberry bushy dwarf virus (RBDV), recently renamed to Idaeovirus rubi, is one of the most common viruses infecting Rubus species worldwide but there is still a limited number of genome sequences available in the GenBank database and the majority of the sequences include partial sequences of RNA-1 and RNA-2. The distribution and incidence of RBDV in main raspberry and blackberry growing provinces in Turkey were monitored during 2015–2019 and 537 Rubus spp. samples were tested by both DAS-ELISA and RT-PCR. Among the tested samples, 36 samples tested positive for RBDV by DAS-ELISA and 67 samples by RT-PCR. There was relatively low nucleotide diversity among the Turkish isolates. Turkish isolates shared 93%–97.7%, 84.3%–98.9%, and 85%–99.2% nucleotide sequence identities with available sequences in the GenBank, in partial RNA-1, movement protein (MP) and coat protein (CP) genes, respectively. In the phylogenetic tree constructed for RNA-1, MP, and CP sequences, all Turkish raspberry isolates were clustered in a distinct clade. However, the blackberry isolates showed considerable variation in nucleotide sequences and were placed in three distinct groups. The divergent blackberry isolates showed high variability in MP (84.5%–89.3%) and CP (85.5%–89.7%) regions and were placed in a distinct group. The rest of blackberry isolates clustered together with sweet cherry RBDV isolates adjacent to the grapevine clade or together with raspberry isolates. The comparative analysis conducted on three RNA segments of RBDV highlighted the high sequence diversity of Turkish RBDV isolates. This study also emphasizes the importance of regular monitoring of RBDV infections in Turkey, with special regard to those Rubus spp. and grapevine accessions employed in conservation and selection programmes. In particular, the presence of new RBDV genetic variants and infection of Rubus species must be taken into account to choose a correct detection protocol and management strategy.     

Intracellular delivery of trehalose renders mesenchymal stromal cells viable and immunomodulatory competent after cryopreservation

Cytotechnology - Trehalose is a nontoxic disaccharide and a promising cryoprotection agent for medically applicable cells. In this study, the efficiency of combining trehalose with reversible...     

A unique enzyme of acetic acid bacteria, PQQ-dependent alcohol dehydrogenase, is also present in Frateuria aurantia

A membrane-bound, pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenase (ADH) was purified from Frateuria aurantia LMG 1558^T. Although F. aurantia belongs to a group of γ-Proteobacteria, the characteristics of its PQQ-ADH were similar to the enzyme characteristics of the typical high-acetic acid-resistant bacterium Gluconacetobacter europaeus from the group of α-Proteobacteria. The PQQ-dependent ADH was solubilized from the membranes and purified after anionic, cationic, and affinity chromatography with specific activity of 117 U/mg. The purified enzyme was estimated to be composed of two subunits of ca. 72 and 45 kDa, as judged by SDS-polyacrylamide gel electrophoresis. The purified enzyme had maximum activity at pH 4.5 and showed the highest substrate specificity to ethanol, isoamyl alcohol, 1-butanol, and 1-propanol. The deduced sequences of cloned genes adhA and adhB encoding subunits I and II of PQQ-ADH showed 80 % amino acid (AA) identity to AdhA and 68 % AA identity to AdhB of Ga. europaeus V3 (LMG 18494). Because of the high similarity between genes encoding subunits I and II of PQQ-ADH and its homologous genes found in a distantly related taxonomic group of acetic acid bacteria, the results suggest the possibility of horizontal gene transfer between these two groups of genera.     

Pre-treatment with salicylic acid induces phenolic responses of Norway spruce (<Emphasis Type="Italic">Picea abies</Emphasis>) bark to bark beetle (<Emphasis Type="Italic">Ips typographus</Emphasis>) attack

Keymessage

The temporal gradations of the investigated phenolics in Norway spruce bark after bark beetle (Ips typographus) attack followed the general eco-physiological concept. Treatment with salicylic acid inhibits bark beetle colonisation, alleviates the phenolic responses and activates the synthesis of condensed tannins on later sampling dates.

Abstract

Conifer bark is the target of numerous organisms due to its assimilated transport and nutrient storage functions. In the presented study, 100 mM salicylic acid (SA) was applied onto Norway spruce stems prior to being infested with bark beetles (Ips typographus L.), to study the temporal gradation of changes in condensed tannins (CT) and total phenolics (tPH) and their significance for mediating stress-tolerance. A significant accumulation of CT was monitored in untreated trees in response to progressive bark beetle infestation occurring from May onwards. In SA-treated infested trees, the CT values remained at control levels until May, but after the re-treatment of infested trees in June, the concentrations of CT rose significantly in comparison to the controls. The tPH values dropped 16 days after SA-treatment, independent of infestation, and later on remained at control level until July. In contrast, tPH contents accumulated in untreated infested trees in May, eased in June and increased again in July, when the trees were affected by the second generation of bark beetles. To sum up, in May and July when the highest beetle-flight activity was monitored the metabolic shift of phenolics within untreated infested trees differed significantly from the response of SA-treated trees. In addition, on SA-treated trees less entrance holes were monitored over the whole period of sampling when compared to untreated infested trees. These results provide evidence that SA-treatment alleviates the phenolic responses, activates the synthesis of condensed tannins and inhibits bark beetle colonisation.

     

<Emphasis Type="Italic">Yersinia enterocolitica</Emphasis> type III secretion: Evidence for the ability to transport proteins that are folded prior to secretion

Background  

Pathogenic Yersinia species (Y. enterocolitica, Y. pestis, Y. pseudotuberculosis) share a type three secretion system (TTSS) which allows translocation of effector proteins (called Yops) into host cells. It is believed that proteins are delivered through a hollow needle with an inner diameter of 2–3 nm. Thus transport seems to require substrates which are essentially unfolded. Recent work from different groups suggests that the Yersinia TTSS cannot accommodate substrates which are folded prior to secretion. It was suggested that folding is prevented either by co-translational secretion or by the assistance of specific Yop chaperones (called Sycs).     

Invasiveness of transformed human breast epithelial cell lines is related to cathepsin B and inhibited by cysteine proteinase inhibitors

The activities'of the lysosomal cysteine proteinases cathepsin B and L are regulated by their endogenous inhibitors, stefins A and B, and cystatin C, and their imbalance may be associated with increased invasiveness and development of the malignant cell phenotype. The aim of this study was to investigate mRNA, protein and activity levels of the above proteins in relation to in vitro invasiveness and to the reported in vivo tumorigenicity of four human breast tumor cell lines: the spontaneously immortalized cell line MCF10A, its c-Ha-ras transfectant MCF10AT, and two tumorigenic derivative cell lines, MCF10AT-Ca1a and MCF10AT-Ca1d. Invasiveness did not correlate with tumorigenicity, since the MCF10AT cell was the most invasive and the remaining three were at about half of its level. Cathepsin B expression paralleled the in vitro invasiveness through matrigel at all levels of expression, but cathepsin L did not. Stefin levels were elevated several-fold in the tumorigenic cell lines, but not in MCF10AT. The hypothesis that cathepsin B plays an active role in the invasion of breast cancer cell lines was confirmed by the fact that synthetic cysteine proteinase inhibitors, particularly those selective for cathepsin B, significantly reduced the invasion of the MCF10AT cells.     

The response of giant phospholipid vesicles to pore-forming peptide melittin

The interaction between the pore-forming peptide melittin (MLT) and giant phospholipid vesicles was explored experimentally. Micromanipulation and direct optical observation of a vesicle (loaded with sucrose solution and suspended in isomolar glucose solution) enabled the monitoring of a single vesicle response to MLT. Time dependences of the vesicle size, shape and the composition of the inner solution were examined at each applied concentration of MLT (in the range from 1 to 60 μg/ml). The response varied with MLT concentration from slight perturbation of the membrane to disintegration of the vesicle. A model for MLT-vesicle interaction is proposed that explains the observed phenomena in the entire span of MLT concentrations and is consistent with deduced underlying mechanisms of MLT action: trans-membrane positioning and dimerization of MLT, the lipid flow from the outer to the inner membrane leaflet induced by MLT translocation, formation of pores and the consequent transport of small molecules through the membrane. The results of the theoretical analysis stress the role of dimers in the MLT-membrane interaction and demonstrate that the MLT-induced membrane permeability for sugar molecules in this experimental set-up depends on both MLT concentration and time.     

Intermediate Monocytes but Not TIE2-Expressing Monocytes Are a Sensitive Diagnostic Indicator for Colorectal Cancer

We have conducted the first study to determine the diagnostic potential of the CD14++CD16+ intermediate monocytes as compared to the pro-angiogenic subset of CD14++CD16+TIE2+ TIE2-expressing monocytes (TEMs) in cancer. These monocyte populations were investigated by flow cytometry in healthy volunteers (N?=?32) and in colorectal carcinoma patients with localized (N?=?24) or metastatic (N?=?37) disease. We further determined blood levels of cytokines associated with monocyte regulation. The results revealed the intermediate monocyte subset to be significantly elevated in colorectal cancer patients and to show the highest frequencies in localized disease. Multivariate regression analysis identified intermediate monocytes as a significant independent variable in cancer prediction. With a cut-off value at 0.37% (intermediate monocytes of total leukocytes) the diagnostic sensitivity and specificity ranged at 69% and 81%, respectively. In contrast, TEM levels were elevated in localized cancer but did not differ significantly between groups and none of the cytokines correlated with monocyte subpopulations. Of interest, in vitro analyses supported the observation that intermediate monocytes were more potently induced by primary as opposed to metastatic cancer cells which may relate to the immunosuppressive milieu established in the advanced stage of metastatic disease. In conclusion, intermediate monocytes as compared to TIE2-expressing monocytes are a more sensitive diagnostic indicator of colorectal cancer.     

Comparison of various methods of estimating radon dose at underground workplaces in wineries

Levels of radon were surveyed in the air at underground workplaces of eight major Slovenian wineries. Geometric mean and geometric standard deviation values, respectively, obtained with different devices were 81 Bq m⁻³ and 2.3 with alpha scintillation cells, 114 Bq m⁻³ and 2.0 by exposing etched track detectors for 1–5 months, and 183 Bq m⁻³ and 2.6 from 1–4-weeks continuous measurements. The equilibrium factor was 0.25–0.67, and the unattached fraction of radon short-lived decay products was in the range 0.09–0.20. Effective doses were calculated and compared based on radon data obtained with different techniques.