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Background and AimsThe programmed softening occurring during fruit development requires scission of cell wall polysaccharides, especially pectin. Proposed mechanisms include the action of wall enzymes or hydroxyl radicals. Enzyme activities found in fruit extracts include pectate lyase (PL) and endo-polygalacturonase (EPG), which, in vitro, cleave de-esterified homogalacturonan in mid-chain by β-elimination and hydrolysis, respectively. However, the important biological question of whether PL exhibits action in vivo had not been tested.MethodsWe developed a method for specifically and sensitively detecting in-vivo PL products, based on Driselase digestion of cell wall polysaccharides and detection of the characteristic unsaturated product of PL action.Key ResultsIn model in-vitro experiments, pectic homogalacturonan that had been partially cleaved by commercial PL was digested to completion with Driselase, releasing an unsaturated disaccharide (‘ΔUA–GalA’), taken as diagnostic of PL action. ΔUA–GalA was separated from saturated oligogalacturonides (EPG products) by electrophoresis, then subjected to thin-layer chromatography (TLC), resolving ΔUA–GalA from higher homologues. The ΔUA–GalA was confirmed as 4-deoxy-β-l-threo-hex-4-enopyranuronosyl-(1→4)-d-galacturonic acid by NMR spectroscopy. Driselase digestion of cell walls from ripe fruits of date (Phoenix dactylifera), pear (Pyrus communis), rowan (Sorbus aucuparia) and apple (Malus pumila) yielded ΔUA–GalA, demonstrating that PL had been acting in vivo in these fruits prior to harvest. Date-derived ΔUA–GalA was verified by negative-mode mass spectrometry, including collision-induced dissociation (CID) fragmentation. The ΔUA–GalA:GalA ratio from ripe dates was roughly 1:20 (mol mol–1), indicating that approx. 5 % of the bonds in endogenous homogalacturonan had been cleaved by in-vivo PL action.ConclusionsThe results provide the first demonstration that PL, previously known from studies of fruit gene expression, proteomic studies and in-vitro enzyme activity, exhibits enzyme action in the walls of soft fruits and may thus be proposed to contribute to fruit softening.

Introduction:The Sultanate of Oman is rich in diversity of the most important crops like wheat, which not only has a global significance but is also regarded as one of the strategic crops in the country. The country has an ancient cultivation history of both bread wheat (Triticum aestivumL.s.l.) and durum wheat (Triticum turgidumsub sp.durum) because of its characteristic location on the eastern edge of the Arabian Peninsula. Wheat landraces constitute the prime genetic resources of cultivated wheat not only in Oman but also in several MENA (the Middle East and North Africa) countries. Indigenous landraces have paramount significance for their potential utilization in crop improvement and conservation programs. Hence, the present study was undertaken to subject 17 indigenous durum wheat accessions for analyses of diversity to select parents for hybridization in national crop improvement programs.Materials and Methods:The trial was conducted consecutively for two cropping seasons (2017-2018 and 2018-2019) during winter from November to March on the layouts of a loamy soil site under sprinkler irrigation system in Augmented Design with five check varieties replicated five times randomized and distributed throughout the experimental area under spacing and crop husbandry practices as per national recommendations. The data on 9 quantitative (Plant descriptors) and 6 qualitative traits on the presence (score 1) or absence (score 0) of pigmentation on 6 plant parts were collected. These traits were subjected to both Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) to comprehend the contribution of these characters towards diversity and form prime diverse clusters from 17 indigenous durum wheat landraces to select appropriate parents for crossing.Results:The results indicated that indigenous durum wheat accessions were significantly different (p>0.05) with respect to all the quantitative characters except the number of tillers. Of 36 combinations of associations among 9 agro-morphological characters’ studied, only six correlations involving four charactersviz. tiller no., spikelets/ spike, grains/spike, and grain length were found significant (pConclusion:The indigenous durum wheat landraces / accessions were found to be more diverse and potential for use in the national crop improvement programs for higher productivity.

A 12-year-old girl with right cerebellar pilocytic astrocytoma and left Ventricular – Peritoneal (VP) shunt presented with prolonged progressive painful abdominal distention, constipation, significant weight loss and intermittent fever. Laboratory investigations including blood and CerebroSpinal Fluid (CSF) tests revealed a VP shunt infection with Brucella abortus + Brucella melitensis. Abdominal Computed Tomography (CT) scans revealed a large abdominopelvic cyst with enhancing wall suspicious for infected pseudocyst. Ovarian tumor markers including AFP, CA-125, CA 19-9 and CEA were negative. Brucella was detected in cyst fluid by Real Time -Polymerase Chain Reaction (RT -PCR). The patient had her infected shunt removed, with establishment of External Ventricular Drainage (EVD) and treatment with antibiotics. A final diagnosis of neurobrucellosis was made and she responded well to 6 months therapy of oral doxycycline, oral rifampicin and oral cotrimoxazole. This case highlights a rare occurrence of neurobrucella in patients with VP shunts and excellent response to source control and antimicrobial therapy.

Overexpression of the BRE (brain and reproductive organ-expressed) gene defines a distinct pediatric and adult acute myeloid leukemia (AML) subgroup. Here we identify a promoter enriched for active chromatin marks in BRE intron 4 causing strong biallelic expression of a previously unknown C-terminal BRE transcript. This transcript starts with BRE intron 4 sequences spliced to exon 5 and downstream sequences, and if translated might code for an N terminally truncated BRE protein. Remarkably, the new BRE transcript was highly expressed in over 50% of 11q23/KMT2A (lysine methyl transferase 2A)-rearranged and t(8;16)/KAT6A-CREBBP cases, while it was virtually absent from other AML subsets and normal tissues. In gene reporter assays, the leukemia-specific fusion protein KMT2A-MLLT3 transactivated the intragenic BRE promoter. Further epigenome analyses revealed 97 additional intragenic promoter marks frequently bound by KMT2A in AML with C-terminal BRE expression. The corresponding genes may be part of a context-dependent KMT2A-MLLT3-driven oncogenic program, because they were higher expressed in this AML subtype compared with other groups. C-terminal BRE might be an important contributor to this program because in a case with relapsed AML, we observed an ins(11;2) fusing CHORDC1 to BRE at the region where intragenic transcription starts in KMT2A-rearranged and KAT6A-CREBBP AML.Leukemia advance online publication, 24 October 2017; doi:10.1038/leu.2017.280.

It is quite challenging to recover heavy crude oil due to its high viscosity and long chain hydrocarbon contents. In this study the isolation of thermophilic bacterial consortia from crude oil contaminated soil samples and their ability to degrade heavy crude oil were investigated. Thermophilic spore forming bacteria were inoculated with heavy oil in minimal salt media. Maximum growth was observed on 21st day of incubation at 40 °C. Samples were analyzed for biosurfactant production, where a substantial decrease in surface tension and interfacial tension was not observed. A well-assay was used to check the potential of bacterial consortia for oil-clearing zones on oil agar plate with bacterial cultures and their cell-free filtrates. 16S rRNA sequencing of 27 isolates from oil contaminated soil showed that isolates belonged to three classes: Alpha-proteobacteria, gamma-proteobacteria and Bacilli. Scanning electron microscopy showed that the oil utilizing bacteria were rod-shaped with rough surface and fimbria. Gas chromatography analysis of treated oil after 21 days showed that bacterial consortia efficiently degraded heavy crude oil to light hydrocarbons ranging from C11–C27, from initial C37+ carbon chain of untreated controls. These bacterial consortia showed potential in heavy crude oil biodegradation by breaking it down to smaller hydrocarbon composition.

Cellular immunotherapy has proven to be effective in the treatment of hematological cancers by donor lymphocyte infusion after allogeneic hematopoietic stem cell transplantation and more recently by targeted therapy with chimeric antigen or T-cell receptor-engineered T cells. However, dependent on the tissue distribution of the antigens that are targeted, anti-tumor responses can be accompanied by undesired side effects. Therefore, detailed tissue distribution analysis is essential to estimate potential efficacy and toxicity of candidate targets for immunotherapy of hematological malignancies. We performed microarray gene expression analysis of hematological malignancies of different origins, healthy hematopoietic cells and various non-hematopoietic cell types from organs that are often targeted in detrimental immune responses after allogeneic stem cell transplantation leading to graft-versus-host disease. Non-hematopoietic cells were also cultured in the presence of IFN-γ to analyze gene expression under inflammatory circumstances. Gene expression was investigated by Illumina HT12.0 microarrays and quality control analysis was performed to confirm the cell-type origin and exclude contamination of non-hematopoietic cell samples with peripheral blood cells. Microarray data were validated by quantitative RT-PCR showing strong correlations between both platforms. Detailed gene expression profiles were generated for various minor histocompatibility antigens and B-cell surface antigens to illustrate the value of the microarray dataset to estimate efficacy and toxicity of candidate targets for immunotherapy. In conclusion, our microarray database provides a relevant platform to analyze and select candidate antigens with hematopoietic (lineage)-restricted expression as potential targets for immunotherapy of hematological cancers.

Monoclonal antibodies (MAbs) and polyclonal antibodies (PCs) were produced to antigens of an Australian population of cereal cyst nematode (CCN), Heterodera avenae. MAb IACR CCNj-49.2 recognised an antigen with a molecular weight of approximately 200 kDa, which was immunolocalised apparently in granules in the nematode gut. A procedure to extract CCN antigens from soil samples, under laboratory conditions was devised, and 50 g samples of soil containing 5 CCN cysts were processed by two sets of flotation techniques to recover the nematodes. Milling using Ballotini glass beads was then used to release the antigens from the CCN cysts recovered in the float. A double antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA) was the better ELISA format used to identify and quantify the CCN population from the processed soil samples containing up to 20% of organic matter. The threshold limit of detection was estimated by serial dilutions of the soil extracts. It was approximately equivalent to 0.5 eggs or 3.6 eggs per g of soil in a DAS-ELISA, when using respectively the PC or the MAb as the trapping antibody. The assay could be made more sensitive in soils with lower contents of organic matter.