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Draft Genome Sequence of the Type Strain Pseudomonas umsongensis DSM 16611
Get PDFHere, we report the draft genome sequence of Pseudomonas umsongensis type strain DSM 16611. The assembly consists of 14 contigs containing 6,701,403 bp with a GC content of 59.73%
Two mutations in mitochondrial ATP6 gene of ATP synthase, related to human cancer, affect ROS, calcium homeostasis and mitochondrial permeability transition in yeast
Get PDFThe relevance of mitochondrial DNA (mtDNA) mutations in cancer process is still unknown. Since the mutagenesis of mitochondrial genome in mammals is not possible yet, we have exploited budding yeast S. cerevisiae as a model to study the effects of tumor-associated mutations in the mitochondrial MTATP6 gene, encoding subunit 6 of ATP synthase, on the energy metabolism. We previously reported that four mutations in this gene have a limited impact on the production of cellular energy. Here we show that two mutations, Atp6-P163S and Atp6-K90E (human MTATP6-P136S and MTATP6-K64E, found in prostate and thyroid cancer samples, respectively), increase sensitivity of yeast cells both to compounds inducing oxidative stress and to high concentrations of calcium ions in the medium, when Om45p, the component of porin complex in outer mitochondrial membrane (OM), was fused to GFP. In OM45-GFP background, these mutations affect the activation of yeast permeability transition pore (yPTP, also called YMUC, yeast mitochondrial unspecific channel) upon calcium induction. Moreover, we show that calcium addition to isolated mitochondria heavily induced the formation of ATP synthase dimers and oligomers, recently proposed to form the core of PTP, which was slower in the mutants. We show the genetic evidence for involvement of mitochondrial ATP synthase in calcium homeostasis and permeability transition in yeast. This paper is a first to show, although in yeast model organism, that mitochondrial ATP synthase mutations, which accumulate during carcinogenesis process, may be significant for cancer cell escape from apoptosis
Mutations in the Non-Catalytic Subunit Dpb2 of DNA Polymerase Epsilon Affect the Nrm1 Branch of the DNA Replication Checkpoint
Get PDFDiverse roles of Dpb2, the non-catalytic subunit of DNA polymerase ε
Get PDFTimely progression of living cells through the cell cycle is precisely regulated. This involves a series of phosphorylation events which are regulated by various cyclins, activated in coordination with the cell cycle progression. Phosphorylated proteins govern cell growth, division as well as duplication of the genetic material and transcriptional activation of genes involved in these processes. A subset of these tightly regulated genes, which depend on the MBF transcription factor and are mainly involved in DNA replication and cell division, is transiently activated at the transition from G1 to S phase. A Saccharomyces cerevisiae mutant in the Dpb2 non-catalytic subunit of DNA polymerase ε (Polε) demonstrates abnormalities in transcription of MBF-dependent genes even in normal growth conditions. It is, therefore, tempting to speculate that Dpb2 which, as described previously, participates in the early stages of DNA replication initiation, has an impact on the regulation of replication-related genes expression with possible implications for genomic stability
Ocena jakości handlowych mąk całoziarnowych - pszennej orkiszowej, pszennej zwyczajnej i żytniej oraz uzyskanych z nich zakwasów spontanicznych Quality Assessment of Commercial Wholegrain Flours Produced from Spelt Wheat, Common Wheat and Rye, and of Spontaneous Sourdough Prepared with Them
Get PDFCelem pracy była próba wyprodukowania zakwasów spontanicznych z całoziarnowej mąki z pszenicy zwyczajnej, pszenicy orkisz oraz z mąki żytniej. W badanych mąkach oznaczono zawartość: wody, popiołu, wybranych składników mineralnych, białka ogółem, tłuszczu surowego, błonnika pokarmowego, wybranych mikotoksyn oraz fosforanów mio-inozytolu. Oznaczono ponadto kwasowość tłuszczową, kwasowość potencjalną, liczbę opadania (LO) oraz ilość glutenu i indeks glutenowy. Ze wszystkich całoziarnowych mąk sporządzono zakwasy, które kontrolowano przez 4 dni poprzez oznaczanie kwasowości czynnej (pH) i kwasowości potencjalnej.
Całoziarnowe mąki z pszenicy orkisz odznaczały się większą zawartością białka, związków tłuszczowych i związków mineralnych, ale mniejszą zawartością błonnika całkowitego w porównaniu z mąkami uzyskanymi z pszenicy zwyczajnej i żyta. Wszystkie mąki całoziarnowe (z wyjątkiem orkiszowej MO1) charakteryzowały się podobną zawartością fosforanów mio-inozytolu w formie IP6 i IP2, jedynie mąka żytnia odznaczała się dodatkowo formami IP5 i IP3. W żadnej z badanych mąk pszennych nie oznaczono zawartości mikotoksyn, tj. DON i zearalenonu, z wyjątkiem mąki z pszenicy orkisz MO1, w której zidentyfikowano śladowe jego ilości. Zakwasy otrzymane z mąk całoziarnowych z pszenicy orkisz po 72 h fermentacji w temp. 30 ºC charakteryzowały się większą kwasowością w porównaniu z zakwasami z mąki z pszenicy zwyczajnej, a bardziej zbliżoną do zakwasów żytnich. Zatem wszystkie otrzymane zakwasy można stosować do produkcji chlebów ze 100-procentowej mąki całoziarnowej z żyta, pszenicy orkisz i pszenicy zwyczajnej, w miejsce stosowanego dotychczas w praktyce zakwasu żytniego.
The objective of the study was an attempt to produce spontaneous sourdoughs from wholegrain flours made from common wheat, spelt wheat, and rye. In the flours analyzed, the following was determined: water content, ash, selected mineral components, total protein, raw fat, dietary fibre, selected mycotoxins, and myo-inositol phosphates. Moreover, there were determined fat acidity, potential acidity, falling number as well as the content of gluten and gluten index. Using every type of the wholegrain flours tested, sourdoughs were produced; they were, further, monitored for 4 days by determining the active acidity (pH) and titratable acidity.
In comparison to flours made from common wheat and rye, the wholegrain spelt wheat flours were distinguished by higher contents of protein, fat, and mineral compounds; however, they had less total fibre. All the wholegrain flours (except MO1 spelt flour) were characterized by a similar content of myoinositol phosphates in the form of IP6 and IP2, but only the rye flour was additionally distinguished by the IP5 and IP3 forms. Mycotoxins, i.e. DON and zearalenone, were not found in any wheat flours except for the MO1 spelt flour, in which trace amounts of zearalenone were identified. Sourdoughs produced from the wholegrain spelt flour after the 72 h fermentation at 30 ºC were characterized by a greater acidity compared to those produced from the wheat flour and their acidity was more similar to that of the rye sourdoughs. Thus, all the types of sourdough obtained can be used to produce bread from 100 % wholegrain flour made from rye, spelt, and common wheat
U7 snRNP is recruited to histone pre-mRNA in a FLASH-dependent manner by two separate regions of the stem-loop binding protein
Get PDFCleavage of histone pre-mRNAs at the 3' end requires stem-loop binding protein (SLBP) and U7 snRNP that consists of U7 snRNA and a unique Sm ring containing two U7-specific proteins: Lsm10 and Lsm11. Lsm11 interacts with FLASH and together they bring a subset of polyadenylation factors to U7 snRNP, including the CPSF73 endonuclease that cleaves histone pre-mRNA. SLBP binds to a conserved stem-loop structure upstream of the cleavage site and acts by promoting an interaction between the U7 snRNP and a sequence element located downstream from the cleavage site. We show that both human and Drosophila SLBPs stabilize U7 snRNP on histone pre-mRNA via two regions that are not directly involved in recognizing the stem-loop structure: helix B of the RNA binding domain and the C-terminal region that follows the RNA binding domain. Stabilization of U7 snRNP binding to histone pre-mRNA by SLBP requires FLASH but not the polyadenylation factors. Thus, FLASH plays two roles in 3' end processing of histone pre-mRNAs: It interacts with Lsm11 to form a docking platform for the polyadenylation factors, and it cooperates with SLBP to recruit U7 snRNP to histone pre-mRNA
Draft Genome Sequence of the Type Strain Sphingopyxis witflariensis DSM 14551
Get PDFHere, we present the draft genome sequence of Sphingopyxis witflariensis strain DSM 14551. The assembly consists of 38 contigs and contains 4,306,761 bp, with a GC content of 63.3%
Ammonia Reduces Intracellular Asymmetric Dimethylarginine in Cultured Astrocytes Stimulating Its y+LAT2 Carrier-Mediated Loss
Get PDFPreviously we had shown that ammonia stimulates nitric oxide (NO) synthesis in astrocytes by increasing the uptake of the precursor amino acid, arginine via the heteromeric arginine/glutamine transporter y+LAT2. Ammonia also increases the concentration in the brain of the endogenous inhibitor of nitric oxide synthases (NOS), asymmetric dimethylarginine (ADMA), but distribution of ADMA surplus between the intraastrocytic and extracellular compartments of the brain has not been studied. Here we tested the hypothesis that ammonia modulates the distribution of ADMA and its analog symmetric dimethylarginine (SDMA) between the two compartments of the brain by competition with arginine for the y+LAT2 transporter. In extension of the hypothesis we analyzed the ADMA/Arg interaction in endothelial cells forming the blood-brain barrier. We measured by high-performance liquid chromatography (HPLC) and mass spectrometry (MS) technique the concentration of arginine, ADMA and SDMA in cultured cortical astrocytes and in a rat brain endothelial cell line (RBE-4) treated with ammonia and the effect of silencing the expression of a gene coding y+LAT2. We also tested the expression of ADMA metabolism enzymes: protein arginine methyltransferase (PRMT) and dimethylarginine dimethyl aminohydrolase (DDAH) and arginine uptake to astrocytes. Treatment for 48 h with 5 mM ammonia led to an almost 50% reduction of ADMA and SDMA concentration in both cell types, and the effect in astrocytes was substantially attenuated by silencing of the Slc7a6 gene. Moreover, the y+LAT2-dependent component of ammonia-evoked arginine uptake in astrocytes was reduced in the presence of ADMA in the medium. Our results suggest that increased ADMA efflux mediated by upregulated y+LAT2 may be a mechanism by which ammonia interferes with intra-astrocytic (and possibly intra-endothelial cell) ADMA content and subsequently, NO synthesis in both cell types
Total testosterone to dihydrotestosterone ratio assessed by LC-MS/MS predicts a worse metabolic profile not only in PCOS patients
Get PDFObjectives:
Total testosterone/dihydrotestosterone ratio (TT/DHT) was found to determine metabolic risk in polycystic ovary syndrome (PCOS). The aim of this study was to analyze whether (TT/DHT) may be helpful in predicting metabolic risk not only in PCOS patients but also in healthy women.
Material and methods:
Total testosterone (TT), dihydrotestosterone (DHT), androstendione and dehydroepiandrosterone sulphate (DHEA-S) were measured by LC-MS/MS in 36 women with PCOS and in 29 age-matched controls without clinical hyperandrogenism. In all participants, anthropometric data, lipids, adipose tissue percent (%fat), HOMA-IR were also assessed.
Results:
The studied groups were not different in terms of age, BMI, waist circumference, %fat and HOMA-IR. In the patients group, mean TT and androstendione levels were significantly higher as compared to controls (1.4 nmol/L vs. 1.0 nmol/L, P < 0.001) and (6.6 nmol/L vs. 4.9 nmol/L, P < 0.01), respectively. In the patients group, mean TT/DHT ratio was significantly higher compared to controls (3.6 vs. 2.7, P < 0.01) and correlated with BMI (r = 0.37, P < 0.05), waist circumference (r = 0.44, P < 0.01), %fat (r = 0.30, P < 0.05), as well as with insulin levels (r = 0.38, P < 0.05) and HOMA-IR (r = 0.44, P < 0.05). The association between TT/DHT ratio and unfavorable metabolic parameters was also seen in controls.
Conclusion:
Total testosterone/dihydrotestosterone ratio assessed by LC-MS/MS correlates with a worse metabolic profile not only in PCOS patients, but also in healthy women
Evaluation of Anti-cancer Activity of Stilbene and Methoxydibenzo[b,f] oxepin Derivatives
Get PDFBackground: Stilbenes, 1,2-diphenylethen derivatives, including resveratrol and combretastatins, show anticancer features especially against tumor angiogenesis. Fosbretabulin, CA-4, in combination with carboplatin, is in the last stages of clinical tests as an inhibitor of thyroid cancer. The mode of action of these compounds involves suppression of angiogenesis through interfering with tubulin (de)polymerization. Objective: We have previously synthesized five E-2-hydroxystilbenes and seven dibenzo[b,f]oxepins in Z configuration, with methyl or nitro groups at varied positions. The aim of the present work was to evaluate the anticancer activity and molecular mechanism(s) of action of these compounds. Results: Two healthy, EUFA30 and HEK293, and two cancerous, HeLa and U87, cell lines were treated with four newly synthetized stilbenes and seven oxepins. Two of these compounds, JJR5 and JJR6, showed the strongest cytotoxic effect against cancerous cells tested and these two were selected for further investigations. They induced apoptosis with sub-G1 or S cell cycle arrest and PARP cleavage, with no visible activation of caspases 3 and 7. Proteomic differential analysis of stilbene-treated cells led to the identification of proteins involved almost exclusively in cell cycle management, apoptosis, DNA repair, and stress response, e. g. oxidative stress. Conclusions: Among newly synthesized stilbene derivatives we selected two as potent anticancer compounds triggering late apoptosis/necrosis in cancerous cells through sub-G1 phase cell cycle arrest. They changed cyclin expression, induced DNA repair mechanisms, enzymes involved in apoptosis, and oxidative stress response. Compounds JJR5 and JJR6 can be a base for structure modification(s) to obtain even more active derivatives