Membrane Lipids and Osmolytes in the Response of the Acidophilic Basidiomycete Phlebiopsis gigantea to Heat, Cold, and Osmotic Shocks.

Previously, we found for the first time the participation of osmolytes in adaptation to acidic conditions in three acidophilic fungi. Because trehalose can protect membranes, we hypothesized a relationship between osmolyte and membrane systems in adaptation to stressors. In the mycelium of Phlebiopsis gigantea, the level of osmolytes reaches 8% of the dry mass, while trehalose and arabitol make up 60% and 33% of the sum, respectively. Cold shock does not change the composition of osmolytes, heat shock causes a twofold increase in the trehalose level, and osmotic shock leads to a marked increase in the amount of trehalose and arabitol. Predominance of phospholipids (89% of the sum) and low proportions of sterols and sphingolipids are characteristic features of the membrane lipids' composition. Phosphatidic acids, along with phosphatidylethanolamines and phosphatidylcholines, are the main membrane lipids. The composition of the membrane lipids remains constant under all shocks. The predominance of linoleic (75% of the sum) and palmitic (20%) acids in phospholipids results in a high degree of unsaturation (1.5). Minor fluctuations in the fatty acid composition are observed under all shocks. The results demonstrate that maintaining or increasing the trehalose level provides stability in the membrane lipid composition during adaptation.

Current status of phosphoinotiside-3 kinase inhibitors in blood cancers.

PURPOSE OF REVIEW: Treatment of non-Hodgkin lymphoma (NHL) and chronic lymphocytic leukemia (CLL) underwent paradigm shifts, with targeted agents rapidly displacing chemotherapy. Phosphoinotiside-3 kinase (PI3K) is essential for survival and proliferation of neoplastic B cells and has proven a tractable target in NHL, with four agents receiving FDA approval in the last decade. This review summarizes key data and challenges associated with use of PI3K inhibitors in routine practice. RECENT FINDINGS: Idelalisib and duvelisib are active in CLL and indolent NHL, including in patients with high-risk features. Despite differential targeting of PI3K isoforms, they exhibit comparable efficacy and adverse event profile including autoimmune events (transaminitis, colitis, pneumonitis), mediated by Treg/Th17 imbalance. Although copanlisib, a pan-PI3K inhibitor, is associated with a distinct safety profile (hyperglycemia, hypertension), preclinical studies indicate that umbralisib, a dual inhibitor of PI3Kδ and casein kinase 1ε, may have less effect on Tregs. However, both drugs may still cause immune-mediated toxicities. SUMMARY: With close monitoring and management of adverse events, PI3K inhibitors continue to have a role in therapy of R/R CLL and NHL. Strategies to mitigate adverse events and increase efficacy of PI3K inhibitors include time-limited combination approaches, intermittent dosing schedules.

Membrane lipid and osmolyte readjustment in the alkaliphilic micromycete Sodiomyces tronii under cold, heat and osmotic shocks.

Previously, we showed for the first time that alkaliphilic fungi, in contrast to alkalitolerant fungi, accumulated trehalose under extremely alkaline conditions, and we have proposed its key role in alkaliphilia. We propose that high levels of trehalose in the mycelium of alkaliphiles may promote adaptation not only to alkaline conditions, but also to other stressors. Therefore, we studied changes in the composition of osmolytes, and storage and membrane lipids under the action of cold (CS), heat (HS) and osmotic (OS) shocks in the obligate alkaliphilic micromycete Sodiomyces tronii. During adaptation to CS, an increase in the degree of unsaturation of phospholipids was observed while the composition of osmolytes, membrane and storage lipids remained the same. Under HS conditions, a twofold increase in the level of trehalose and an increase in the proportion of phosphatidylethanolamines were observed against the background of a decrease in the proportion of phosphatidic acids. OS was accompanied by a decrease in the amount of membrane lipids, while their ratio remained unchanged, and an increase in the level of polyols (arabitol and mannitol) in the fungal mycelium, which suggests their role for adaptation to OS. Thus, the observed consistency of the composition of membrane lipids suggests that trehalose can participate in adaptation not only to extremely alkaline conditions, but also to other stressors - HS, CS and OS. Taken together, the data obtained indicate the adaptability of the fungus to the action of various stressors, which can point to polyextremotolerance.

First Report of Fusarium proliferatum Causing Garlic clove Rot in Russian Federation.

Garlic (Allium sativum L.) is a widely consumed bulbous crop both worldwide and in Russia. About 200,000 tons of garlic is produced in Russia annually (https://rosstat.gov.ru/). Significant pre- and post-harvest losses of garlic regularly occur due to Fusarium sp. (Taylor et al., 2013). Since September 2018, rotting has been observed in Russia during garlic bulb storage (data of the Federal Scientific Vegetable Center, FSVC, Moscow Region). The outer bulb surface looked healthy, but underneath the integumentary scales, the cloves had light brown and brown spots. When grown, diseased plants were characterized by root and bulb disruption and leaf drying; for some cultivars, up to 100% of plants died. In January 2020, cv. Strelets and Dubkovsky bulbs, collected in July 2019, with rot symptoms, were taken from the FSVC storage. Necrotic clove tissue fragments (0.2-0.5 cm) were cut, sanitized with 70% ethanol for 3 min, rinsed with sterile water, and incubated on potato dextrose agar (PDA) with 1 mg/ml ampicillin at 22°C in the dark. Four single-spore cultures were obtained from four diseased bulbs. After 6 days of incubation, the isolates produced abundant aerial white mycelia and acquired a purple pigmentation. The hyphae were hyaline with septation. All isolates (Dubkovsky, Dubkovsky 2, Strelets, and Strelets 2) produced numerous oval unicellular microconidia without septa, 4.1 to 11.6 × 1.3 to 3.4 µm (n = 50) and very few macroconidia with 3-4 septa (21 to 26 × 3 to 4 µm (n = 30)), narrowed at both ends. The cultural and conidial characteristics of the isolates corresponded to Fusarium species (Leslie and Summerell 2006). To determine the species, DNA was extracted from four isolates, and the internal transcribed spacer (ITS), and genes of translation elongation factor 1α (EF1α) and subunits 1 and 2 of DNA-directed RNA polymerase II (RPB1 and RPB2) were amplified and sequenced with primers ITS1/ITS4 (White et al. 1990), EF1/EF2 (O'Donnell et al. 1998a), RPB1-F5/RPB1-R8 (O'Donnell et al. 2010) and fRPB2-5F/fRPB2-7cR (Liu et al. 1999). The obtained sequences were identical for all four isolates. The isolate Strelets sequences were deposited in NCBI GenBank (MW149129 (ITS), MW161161 (EF1α), MW413302 (RPB1) and MW413303 (RPB2)); their analysis in MLST (http://fusarium.mycobank.org) showed 98.8-99.8% similarity to F. proliferatum (NRRL 13582, 13598 and others), which is part of the F. fujikuroi complex (O'Donnell et al. 1998b). The test on pathogenicity was performed two times according to (Leyronas et al. 2018). For this, three replicates of 10 cloves (cv. Strelets) were soaked in a conidial suspension (~106 conidia/ml; Strelets isolate) for 24 h. Ten control cloves were soaked in sterile water. The cloves were incubated on Petri dishes (5 cloves on a dish; on filter paper wettened with sterile water) in the dark at 23°C. After 5 days, brown lesions and white mycelium developed on the surface of the treated cloves. The taxonomic status of the fungus isolated from necrotic tissue was determined as F. proliferatum according to the ITS, EF1α, RPB1 and RPB2 analysis. Garlic basal and bulb rot is known to be caused by F. oxysporum f. sp. cepae and F. proliferatum (Snowdon 1990). This study is the first report of F. proliferatum causing rot of garlic bulbs during storage in Russia. F. proliferatum produces a variety of mycotoxins during bulb infestation, and our findings are important for diagnosing a Fusarium disease and the use of garlic crop in culinary and medicine. Funding The reported study was funded by Russian Foundation for Basic Research, project number 20-316-70009. References: Leslie, J. F., and Summerell, B. A. 2006. Page 224 in: The Fusarium Laboratory Manual. Blackwell, Oxford, UK. https://doi.org/10.1002/9780470278376 Leyronas, C., et al. 2018. Plant Dis. 102:2658 https://doi.org/10.1094/PDIS-06-18-0962-PDN Liu, Y.J. et al. 1999. Mol. Biol. Evol. 16: 1799 https://doi.org/10.1093/oxfordjournals.molbev.a026092 O'Donnell, K, et al. 1998a. Proc Natl Acad Sci USA. 95(5):2044. https://doi.org/10.1073/pnas.95.5.2044. O'Donnell, et al. 1998b. Mycologia 90:465 O'Donnell, K., et al. 2010. J. Clin. Microbiol., 48: 3708 https://doi.org/10.1128/JCM.00989-10 Snowdon, A. L. Pages 250-252 in: A Color Atlas of Post-Harvest Diseases and Disorders of Fruits and Vegetables. Vol. 1. 1990. Wolfe Scientific, London. Taylor, A, et al. 2013. Plant Pathol. 62:103. https://doi.org/10.1111/j.1365-3059.2012.02624.x White, T. J., et al. 1990. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA.

Osmolytes and membrane lipids in adaptive response of thermophilic fungus Rhizomucor miehei to cold, osmotic and oxidative shocks.

In contrast to mesophiles, in which levels of trehalose and phosphatidic acids (PA) increased only under heat shock (HS), in thermophiles trehalose and PA were predominant under optimal growth conditions. To study the role of trehalose protection in the adaptation of thermophiles to various stressors, the composition of osmolytes and membrane lipids in the thermophilic fungus Rhizomucor miehei was studied under cold (CS), osmotic (OS) and oxidative (OxS) shocks. CS resulted in no accumulation of glycerol in the mycelium, while the amount of trehalose decreased. The main lipid changes were the increase in the PA proportion with simultaneous decrease of sterols (St), the increase of the unsaturation degree of polar lipids and the decrease of the ergosterol proportion in total St. OS did not cause changes in the lipid composition, but led to the decrease of ergosterol proportion too. Despite the low ability of Mucorales to produce polyols, increase in the level of arabitol and glycerol was observed under OS. OxS led to the decrease of trehalose level and had no effect on the lipid composition. Thus, our results show the similarity (OS) and the difference (CS and OxS) between adaptation mechanisms of thermophiles and mesophiles.

Lipids and soluble carbohydrates in the mycelium and ascomata of alkaliphilic fungus Sodiomyces alkalinus.

Alkaliphilic fungi are fundamentally different from alkalitolerant ones in terms of mechanisms of adaptation. They accumulate trehalose in cytosol and phosphatidic acids (PA) in the membrane lipids, whereas alkalitolerants contain these compounds in low amounts. But it is unclear how the composition of osmolytes and lipids changes during cytodifferentiation. In this article the composition of lipids and soluble cytosol carbohydrates in the mycelium and fruit bodies of the alkaliphilic fungus Sodiomyces alkalinus was studied. In the mycelium, mannitol and trehalose dominated, while in fruit bodies only trehalose was predominant. Phosphatidylcholines (PC), PA and sterols were major membrane lipids of the mycelium, while PC and sterols were predominant in fruit bodies. The degree of fatty acids unsaturation of the main mycelium phospholipids (PC and PA) increased with age, while that of PC did not change regardless of the developmental stage. In young mycelium, storage lipids were represented mainly by free fatty acids, and in mature mycelium and fruit bodies-by triacylglycerols. Fruit bodies contained three times less membrane lipids and twice as many storage lipids as mycelium. Trehalose was the main cytosol carbohydrate in the mycelium and fruit bodies, which confirms its key value for alkaliphily.

SYK inhibition thwarts the BAFF - B-cell receptor crosstalk and thereby antagonizes Mcl-1 in chronic lymphocytic leukemia.

Although small molecule inhibitors of B-cell receptor-associated kinases have revolutionized therapy in chronic lymphocytic leukemia (CLL), responses are incomplete. Pro-survival signaling emanating from the microenvironment may foster therapeutic resistance of the malignant B cells resident in the protective lymphoid niches. B-cell activating factor (BAFF) is critical to the survival of both healthy and neoplastic B cells. However, the pro-survival pathways triggered by BAFF have not been fully characterized. Here we show that BAFF elicited resistance to spontaneous and drug-induced apoptosis in stromal co-cultures, induced activation of both canonical and non-canonical NFκB signaling pathways, and triggered B-cell receptor signaling in CLL cells, independently of IGHV mutational status. SYK, a proximal kinase in the B-cell receptor signaling cascade, acted via STAT3 to bolster transcription of the anti-apoptotic protein Mcl-1, thereby contributing to apoptosis resistance in BAFF-stimulated cells. SYK inhibitor entospletinib downregulated Mcl-1, abrogating BAFF-mediated cell survival. BAFF-B-cell receptor crosstalk in neoplastic B cells was mediated by SYK interaction with TRAF2/TRAF3 complex. Thus, SYK inhibition is a promising therapeutic strategy uniquely poised to antagonize crosstalk between BAFF and B-cell receptor, thereby disrupting the pro-survival microenvironment signaling in chronic lymphocytic leukemia.

Membrane lipids and soluble sugars dynamics of the alkaliphilic fungus Sodiomyces tronii in response to ambient pH.

Alkaliphily, the ability of an organism to thrive optimally at high ambient pH, has been well-documented in several lineages: archaea, bacteria and fungi. The molecular mechanics of such adaptation has been extensively addressed in alkaliphilic bacteria and alkalitolerant fungi. In this study, we consider an additional property that may have enabled fungi to prosper at alkaline pH: altered contents of membrane lipids and cytoprotectant molecules. In the alkaliphilic Sodiomyces tronii, we showed that at its optimal growth pH 9.2, the fungus accumulates abundant cytosolic trehalose (4-10% dry weight) and phosphatidic acids in the membrane lipids, properties not normally observed in neutrophilic species. At a very high pH 10.2, the major carbohydrate, glucose, was rapidly substituted by mannitol and arabitol. Conversely, lowering the pH to 5.4-7.0 had major implications both on the content of carbohydrates and membrane lipids. It was shown that trehalose dominated at pH 5.4. Fractions of sphingolipids and sterols of plasma membranes rapidly elevated possibly indicating the formation of membrane structures called rafts. Overall, our results reveals complex dynamics of the contents of membrane lipids and cytoplasmic sugars in alkaliphilic S. tronii, suggesting their adaptive functionality against pH stress.

Heat shock response of thermophilic fungi: membrane lipids and soluble carbohydrates under elevated temperatures.

The heat shock (HS) response is an adaptation of organisms to elevated temperature. It includes substantial changes in the composition of cellular membranes, proteins and soluble carbohydrates. To protect the cellular macromolecules, thermophilic organisms have evolved mechanisms of persistent thermotolerance. Many of those mechanisms are common for thermotolerance and the HS response. However, it remains unknown whether thermophilic species respond to HS by further elevating concentrations of protective components. We investigated the composition of the soluble cytosol carbohydrates and membrane lipids of the thermophilic fungi Rhizomucor tauricus and Myceliophthora thermophilaat optimum temperature conditions (41-43 °Ð¡), and under HS (51-53 °Ð¡). At optimum temperatures, the membrane lipid composition was characterized by a high proportion of phosphatidic acids (PA) (20-35 % of the total), which were the main components of the membrane lipids, together with phosphatidylcholines (PC), phosphatidylethanolamines (PE) and sterols (St). In response to HS, the proportion of PA and St increased, and the amount of PC and PE decreased. No decrease in the degree of fatty acid desaturation in the major phospholipids under HS was detected. The mycelium of all fungi at optimum temperatures contained high levels of trehalose (8-10 %, w/w; 60-95 % of the total carbohydrates), which is a hallmark of thermophilia. In contrast to mesophilic fungi, heat exposure decreased the trehalose level and the fungi did not acquire thermotolerance to lethal HS, indicating that trehalose plays a key role in this process. This pattern of changes appears to be conserved in the studied filamentous thermophilic fungi.

Cardiac non-Hodgkin's lymphoma: clinical characteristics and trends in survival.

OBJECTIVES: The purpose of this study was to describe the clinical characteristics and outcomes in cardiac non-Hodgkin's lymphoma (NHL). METHODS: A retrospective analysis of 94 cases of NHL with biopsy-proven cardiac involvement in PubMed between 1990 and 2015. RESULTS: Among cases with cardiac involvement, diffuse large B-cell lymphoma was the most common histologic subtype (58%), followed by T-cell lymphoma (16%), Burkitt's lymphoma (9%), and small lymphocytic lymphoma (6%). Symptomatic heart failure was the most common clinical presentation (34%), and 20% of patients had no cardiac symptoms. Median survival was 3 months (range, 0-72) among all patients. Patients who presented with heart failure had inferior outcomes. Patients with primary, vs. secondary, cardiac involvement had a trend toward superior outcomes. Importantly, chemotherapy treatment was associated with a prolongation in median survival (18 vs. 1 month, HR 0.16, 95% CI, 0.47-0.54, P = 0.0003), and patients diagnosed in the chemo-immunotherapy era demonstrated a trend toward better outcomes. Median survival was not reached among patients with B-cell malignancies who were alive for 1 month after the diagnosis. CONCLUSION: Pathologic lymphomatous involvement of cardiac tissue should be considered in the evaluation of patients with NHL. Durable remissions can be achieved in B-cell NHL with cardiac involvement, and thus, therapy should be considered in such cases.

Methylovulum psychrotolerans sp. nov., a cold-adapted methanotroph from low-temperature terrestrial environments, and emended description of the genus Methylovulum.

Two isolates of aerobic methanotrophic bacteria, strains Sph1T and Sph2, were obtained from cold methane seeps in a floodplain of the river Mukhrinskaya, Irtysh basin, West Siberia. Another morphologically and phenotypically similar methanotroph, strain OZ2, was isolated from a sediment of a subarctic freshwater lake, Archangelsk region, northern Russia. Cells of these three strains were Gram-stain-negative, light-pink-pigmented, non-motile, encapsulated, large cocci that contained an intracytoplasmic membrane system typical of type I methanotrophs. They possessed a particulate methane monooxygenase enzyme and utilized only methane and methanol. Strains Sph1T, Sph2 and OZ2 were able to grow at a pH range of 4.0-8.9 (optimum at pH 6.0-7.0) and at temperatures between 2 and 36 °C. Although their temperature optimum was at 20-25 °C, these methanotrophs grew well at lower temperatures, down to 4 °C. The major cellular fatty acids were C16 : 1ω5c, C16 : 1ω6c, C16 : 1ω7c, C16 : 1ω8c, C16 : 0 and C14 : 0; the DNA G+C content was 51.4-51.9 mol%. Strains Sph1T, Sph2 and OZ2 displayed nearly identical (99.1-99.7 % similarity) 16S rRNA gene sequences and belonged to the family Methylococcaceae of the class Gammaproteobacteria. The most closely related organism was Methylovulum miyakonense HT12T (96.0-96.5 % 16S rRNA gene sequence similarity and 90 % pmoA sequence similarity). The novel isolates, however, differed from Methylovulum miyakonense HT12T by cell morphology, pigmentation, absence of soluble methane monooxygenase, more active growth at low temperatures, growth over a broader pH range and higher DNA G+C content. On the basis of these differences, we propose a novel species, Methylovulum psychrotolerans sp. nov., to accommodate these methanotrophs. Strain Sph1T (=LMG 29227T=VKM B-3018T) is the type strain.

Methylocapsa palsarum sp. nov., a methanotroph isolated from a subArctic discontinuous permafrost ecosystem.

An aerobic methanotrophic bacterium was isolated from a collapsed palsa soil in northern Norway and designated strain NE2T. Cells of this strain were Gram-stain-negative, non-motile, non-pigmented, slightly curved thick rods that multiplied by normal cell division. The cells possessed a particulate methane monooxygenase enzyme (pMMO) and utilized methane and methanol. Strain NE2T grew in a wide pH range of 4.1­8.0 (optimum pH 5.2­6.5) at temperatures between 6 and 32 °C (optimum 18­25 °C), and was capable of atmospheric nitrogen fixation under reduced oxygen tension. The major cellular fatty acids were C18 : 1ω7c, C16 : 0 and C16 : 1ω7c, and the DNA G+C content was 61.7 mol%. The isolate belonged to the family Beijerinckiaceae of the class Alphaproteobacteria and was most closely related to the facultative methanotroph Methylocapsa aurea KYGT (98.3 % 16S rRNA gene sequence similarity and 84 % PmoA sequence identity). However, strain NE2T differed from Methylocapsa aurea KYGT by cell morphology, the absence of pigmentation, inability to grow on acetate, broader pH growth range, and higher tolerance to NaCl. Therefore, strain NE2T represents a novel species of the genus Methylocapsa, for which we propose the name Methylocapsa palsarum sp. nov. The type strain is NE2T ( = LMG 28715T = VKM B-2945T).

Descriptions of Roseiarcus fermentans gen. nov., sp. nov., a bacteriochlorophyll a-containing fermentative bacterium related phylogenetically to alphaproteobacterial methanotrophs, and of the family Roseiarcaceae fam. nov.

A light-pink-pigmented, microaerophilic bacterium was obtained from a methanotrophic consortium enriched from acidic Sphagnum peat and designated strain Pf56(T). Cells of this bacterium were Gram-negative, non-motile, thick curved rods that contained a vesicular intracytoplasmic membrane system characteristic of some purple non-sulfur alphaproteobacteria. The absorption spectrum of acetone/methanol extracts of cells grown in the light showed maxima at 363, 475, 505, 601 and 770 nm; the peaks at 363 and 770 nm are characteristic of bacteriochlorophyll a. However, in contrast to purple non-sulfur bacteria, strain Pf56(T) was unable to grow phototrophically under anoxic conditions in the light. Best growth occurred on some sugars and organic acids under micro-oxic conditions by means of fermentation. The fermentation products were propionate, acetate and hydrogen. Slow chemo-organotrophic growth was also observed under fully oxic conditions. Light stimulated growth. C1 substrates were not utilized. Strain Pf56(T) grew at pH 4.0-7.0 (optimum pH 5.5-6.5) and at 15-30 °C (optimum 22-28 °C). The major cellular fatty acids were 19 : 0 cyclo ω8c and 18 : 1ω7c; quinones were represented by ubiquinone Q-10. The G+C content of the DNA was 70.0 mol%. Strain Pf56 displays 93.6-94.7 and 92.7-93.7% 16S rRNA gene sequence similarity to members of the families Methylocystaceae and Beijerinckiaceae, respectively, and belongs to a large cluster of environmental sequences retrieved from various wetlands and forest soils in cultivation-independent studies. Phenotypic, genotypic and chemotaxonomic characteristics of strain Pf56(T) suggest that it represents a novel genus and species of bacteriochlorophyll a-containing fermentative bacteria, for which the name Roseiarcus fermentans gen. nov., sp. nov. is proposed. Strain Pf56(T) ( = DSM 24875(T) = VKM B-2876(T)) is the type strain of Roseiarcus fermentans, and is also the first characterized member of a novel family within the class Alphaproteobacteria, Roseiarcaceae fam. nov.

Determination of age-dependent bone marrow normocellularity.

OBJECTIVES: Determination of bone marrow cellularity is a key part of bone marrow examination because it provides a small window into a patient's current state of hematopoietic well-being. Traditionally, bone marrow cellularity is estimated semiquantitatively through microscopic examination of core biopsy specimens harvested from the iliac crest of the pelvic bone. Bone marrow cellularity is then designated as hypercellular, normocellular, or hypocellular based on the patient's age. This assessment can have significant clinical impact, but the variation in the age-adjusted normocellularity range is not sufficiently characterized because of a lack of study data, especially in older patients (those older than 70 years of age). This study further established the normal range of bone marrow cellularity, particularly in older adults. METHODS: In this study, 570 benign staging and healthy donor bone marrows from patients 1 year to 93 years of age were analyzed for cellularity. RESULTS: Linear regression modeling demonstrates that cellularity in adults declines approximately 3% per decade, including after the seventh decade of life. The 90% reference interval for normocellularity in United States is 30% to 75% for those aged 18 to 90 years. CONCLUSIONS: The findings revealed a more stable and slower rate of decline in cellularity with age in adults than the widely used linear model of "100% minus the patient age in decades." Normocellularity is better modeled based on age group. In those younger than 20 years of age, normocellularity ranges from 45% to 85% (mean [SD], 65% [20%]), as defined by Friebert et al in 1998. Based on our study finding of a little less than 3% decline per decade of age, the following is our recommendation for normocellularity range: For individuals 20 to 40 years of age, it ranges from 40% to 70% (mean [SD], 55% [15%]); for individuals 40 to 60 years of age, it ranges from 35% to 65% (mean [SD], 50% [15%]); and for individuals older than 60 years of age, it ranges from 30% to 60% (mean [SD], 45% [15%]). Interestingly, those older than 70 years of age do not show a significant decrease from those aged 60 to 69 years.

Epstein-Barr virus-positive, primary cutaneous marginal zone lymphoma, with transformation: Case report and review of the literature.

Epstein-Barr Virus (EBV) positive primary cutaneous marginal zone lymphoma (PCMZL) is uncommon and subsequent transformation is rare. METHODS: We report a patient with EBV positive PCMZL with subsequent transformation to plasmablastic lymphoma and review the literature for transformed PCMZL to assess clinical and pathologic characteristics. In the case we describe, the patient presented with multifocal PCMZL, developed large B cell transformation with plasmacytic differentiation, followed by plasmablastic transformation (PBL), and ultimately died of disease progression despite multiple lines of therapy. Past history was significant for psoriatic arthritis (multiple prior lines of immunomodulatory therapy). The lymphomas and non-involved bone marrow share the same somatic DNMT3A and TET2 mutations, suggesting clonal relatedness and an association with clonal hematopoiesis (CH). RESULTS: Eighteen cases complied the cohort (seventeen cases from the literature and the case reported herein). Nearly half of the eighteen cases of PCMZL with transformation died of progressive disease (44%). Transformed cases were more commonly seen in patients with >2 sites at initial diagnosis. EBV was assessed in 5 patients, 3 were positive (all died of disease). Two patients with NGS studies demonstrated TET2 and DNMT3A mutations. CONCLUSIONS: Transformation of EBV positive PCMZL appears to be a poor prognostic indicator, with our reported case being the first well defined case transformed to PBL, suspected to arise from myeloid-CH.

Pro-apoptotic TP53 homolog TAp63 is repressed via epigenetic silencing and B-cell receptor signalling in chronic lymphocytic leukaemia.

Chronic lymphocytic leukaemia (CLL) is an accumulative disorder marked by deficient apoptosis. The TP53 homolog TAp63 promotes apoptosis and chemosensitivity in solid tumours and its deregulation may contribute to CLL cell survival. We found that TAp63α was the most prevalent TP63 isoform in CLL. Compared to healthy B cells, TAp63 mRNA was repressed in 55·7% of CLL samples. TP63 promoter methylation was high in CLL and inversely correlated with TP63 protein expression in B-cell lymphoma cell lines. siRNA-mediated knockdown of TP63 resulted in partial protection from spontaneous apoptosis accompanied by reductions in PMAIP1 (NOXA), BBC3 (PUMA), and BAX mRNA in CLL cells and increased proliferation of Raji lymphoma cells. TAp63 mRNA levels were higher in CLL with unmutated IGHV. B-cell receptor (BCR) engagement led to repression of TP63 mRNA expression in malignant B cells, while pharmacological inhibition of BCR signalling prevented TP63 downregulation. MIR21, known to target TAp63, correlated inversely with TAp63 expression in CLL, and BCR-mediated downregulation of TP63 was accompanied by MIR21 upregulation in most CLL samples. Our data illustrate the pro-apoptotic function of TP63, provide insights into the mechanisms of BCR-targeting agents, and establish a rationale for designing novel approaches to induce TP63 in CLL and B-cell lymphoma.

Methylomonas paludis sp. nov., the first acid-tolerant member of the genus Methylomonas, from an acidic wetland.

An aerobic methanotrophic bacterium was isolated from an acidic (pH 3.9) Sphagnum peat bog in north-eastern Russia and designated strain MG30(T). Cells of this strain were Gram-negative, pale pink-pigmented, non-motile, thick rods that were covered by large polysaccharide capsules and contained an intracytoplasmic membrane system typical of type I methanotrophs. They possessed a particulate methane monooxygenase enzyme (pMMO) and utilized only methane and methanol. Carbon was assimilated via the ribulose-monophosphate pathway; nitrogen was fixed via an oxygen-sensitive nitrogenase. Strain MG30(T) was able to grow at a pH range of 3.8-7.3 (optimum pH 5.8-6.4) and at temperatures between 8 and 30 °C (optimum 20-25 °C). The major cellular fatty acids were C16:1ω5t, C16:1ω8c, C16:1ω7c and C14:0; the DNA G+C content was 48.5 mol%. The isolate belongs to the family Methylococcaceae of the class Gammaproteobacteria and displayed 94.7-96.9% 16S rRNA gene sequence similarity to members of the genus Methylomonas. However, strain MG30(T) differed from all taxonomically characterized members of this genus by the absence of motility, the ability to grow in acidic conditions and low DNA G+C content. Therefore, we propose to classify this strain as representing a novel, acid-tolerant species of the genus Methylomonas, Methylomonas paludis sp. nov. Strain MG30(T) (=DSM 24973(T)=VKM B-2745(T)) is the type strain.

Acquired thermotolerance, membrane lipids and osmolytes profiles of xerohalophilic fungus Aspergillus penicillioides under heat shock.

Xerophilic fungi accumulate a large amount of glycerol in the cytosol to counterbalance the external osmotic pressure. But during heat shock (HS) majority of fungi accumulate a thermoprotective osmolyte trehalose. Since glycerol and trehalose are synthesized in the cell from the same precursor (glucose), we hypothesised that, under heat shock conditions, xerophiles growing in media with high concentrations of glycerol may acquire greater thermotolerance than those grown in media with high concentrations of NaCl. Therefore, the composition of membrane lipids and osmolytes of the fungus Aspergillus penicillioides, growing in 2 different media under HS conditions was studied and the acquired thermotolerance was assessed. It was found that in the salt-containing medium an increase in the proportion of phosphatidic acids against a decrease in the proportion of phosphatidylethanolamines is observed in the composition of membrane lipids, and the level of glycerol in the cytosol decreases 6-fold, while in the medium with glycerol, changes in the composition of membrane lipids are insignificant and the level of glycerol is reduced by no more than 30%. In the mycelium trehalose level have increased in both media, but did not exceed 1% of dry weight. However, after exposure to HS the fungus acquires greater thermotolerance in the medium with glycerol than in the medium with salt. The data obtained indicate the interrelation between changes in the composition of osmolytes and membrane lipids in the adaptive response to HS, as well as the synergistic effect of glycerol and trehalose.

The Role of Osmolytes and Membrane Lipids in the Adaptation of Acidophilic Fungi.

Acidophiles maintain near-neutral intracellular pH using proton pumps. We have suggested the protective role of osmolytes and membrane lipids in the adaptation to an acidic environment. Previously we have observed, for the first time, high levels of trehalose in acidophilic basidiomycete Sistotrema brinkmannii. Here, we have studied the composition of both osmolytes and membrane lipids of two more acidophilic fungi. Trehalose and polyols were among the main osmolytes during growth under optimal conditions (pH 4.0) in basidiomycete Phlebiopsis gigantea and ascomycete Mollisia sp. Phosphatidic acids, phosphatidylethanolamines, phosphatidylcholines, and sterols, were predominant membrane lipids in both fungi. P. gigantea had a narrow optimum of growth at pH 4.0, resulting in a sharp decline of growth rate at pH 2.6 and 5.0, accompanied by a decrease in the number of osmolytes and significant changes in the composition of membrane lipids. In contrast, Mollisia sp. had a broad optimal growth range (pH 3.0-5.0), and the number of osmolytes either stayed the same (at pH 6.0) or increased (at pH 2.6), while membrane lipids composition remained unchanged. Thus, the data obtained indicate the participation of osmolytes and membrane lipids in the adaptation of acidophilic fungi.

One Step Closer to Enigmatic USCα Methanotrophs: Isolation of a Methylocapsa-like Bacterium from a Subarctic Soil.

The scavenging of atmospheric trace gases has been recognized as one of the lifestyle-defining capabilities of microorganisms in terrestrial polar ecosystems. Several metagenome-assembled genomes of as-yet-uncultivated methanotrophic bacteria, which consume atmospheric CH4 in these ecosystems, have been retrieved in cultivation-independent studies. In this study, we isolated and characterized a representative of these methanotrophs, strain D3K7, from a subarctic soil of northern Russia. Strain D3K7 grows on methane and methanol in a wide range of temperatures, between 5 and 30 °C. Weak growth was also observed on acetate. The presence of acetate in the culture medium stimulated growth at low CH4 concentrations (~100 p.p.m.v.). The finished genome sequence of strain D3K7 is 4.15 Mb in size and contains about 3700 protein-encoding genes. According to the result of phylogenomic analysis, this bacterium forms a common clade with metagenome-assembled genomes obtained from the active layer of a permafrost thaw gradient in Stordalen Mire, Abisco, Sweden, and the mineral cryosol at Axel Heiberg Island in the Canadian High Arctic. This clade occupies a phylogenetic position in between characterized Methylocapsa methanotrophs and representatives of the as-yet-uncultivated upland soil cluster alpha (USCα). As shown by the global distribution analysis, D3K7-like methanotrophs are not restricted to polar habitats but inhabit peatlands and soils of various climatic zones.