Highlight: young research groups in Germany  - 3rd edition.
Highlight: young research groups in Germany - 3rd edition. Biol Chem. 2020 Nov 06;: Authors: Lassak J, Schlundt A PMID: 33159507 [PubMed - as supplied by publisher] (Source: Biological Chemistry)
Source: Biological Chemistry - November 11, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Integrated Ca2+ flux and AFM force analysis in human iPSC-derived cardiomyocytes.
We report impaired Ca2+ handling and reduced contractile force in DCM iPSC-CMs compared to healthy WT controls. TnT-KO iPSC-CMs display no contractile force or Ca2+ transients but generate Ca2+ sparks. We apply our analysis strategy to Ca2+ traces and AFM deflection recordings to reveal maximum rising rate, decay time, and duration of contraction with a multi-step background correction. Our method provides adaptive computing of signal peaks for different Ca2+ flux or force levels in iPSC-CMs, as well as analysis of Ca2+ sparks. Moreover, we report long-term measurements of contractile force dynamics on human iPSC-CMs. This...
Source: Biological Chemistry - October 29, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Thiol switches in membrane proteins - Extracellular redox regulation in cell biology.
Authors: Lorenzen I, Eble JA, Hanschmann EM Abstract Redox-mediated signal transduction depends on the enzymatic production of second messengers such as hydrogen peroxide, nitric oxide and hydrogen sulfite, as well as specific, reversible redox modifications of cysteine-residues in proteins. So-called thiol switches induce for instance conformational changes in specific proteins that regulate cellular pathways e.g., cell metabolism, proliferation, migration, gene expression and inflammation. Reduction, oxidation and disulfide isomerization are controlled by oxidoreductases of the thioredoxin family, including thior...
Source: Biological Chemistry - October 29, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

LOTUS-domain proteins - developmental effectors from a molecular perspective.
Authors: Kubíková J, Reinig R, Salgania HK, Jeske M Abstract The LOTUS domain (also known as OST-HTH) is a highly conserved protein domain found in a variety of bacteria and eukaryotes. In animals, the LOTUS domain is present in the proteins Oskar, TDRD5/Tejas, TDRD7/TRAP/Tapas, and MARF1/Limkain B1, all of which play essential roles in animal development, in particular during oogenesis and/or spermatogenesis. This review summarizes the diverse biological as well as molecular functions of LOTUS-domain proteins and discusses their roles as helicase effectors, posttranscriptional regulators, and critica...
Source: Biological Chemistry - October 26, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Morphological dependent effect of cell-free formed supramolecular fibronectin on cellular activities.
Authors: Le P, Mai-Thi HN, Stoldt VR, Tran NQ, Huynh K Abstract Fibrillar fibronectin (FFN), an active form of fibronectin (FN), plays important roles in various cellular processes. Our goal is to investigate effect of FFN morphology on cellular behaviors. Plasma FN at two concentrations was cross-linked into FFN by dialysis against 2 M urea followed by morphological analysis under Scanning Electron Microscopy. To evaluate effect of FFN morphology, fibroblasts were cultured on FN or different FFNs. Fibroblast behaviors including adhesion, spreading, and migration were evaluated. Our data showed that FN fibrill...
Source: Biological Chemistry - October 20, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

3-Mercaptopyruvate sulfurtransferase: an enzyme at the crossroads of sulfane sulfur trafficking.
Authors: Pedre B, Dick TP Abstract 3-Mercaptopyruvate sulfurtransferase (MPST, also annotated as 3-MST or MST) catalyzes the desulfuration of 3-mercaptopyruvate (3MP) to generate an enzyme-bound hydropersulfide. Subsequently, MPST transfers the persulfide's outer sulfur atom to proteins or small molecule acceptors. MPST activity is known to be involved in hydrogen sulfide (H2S) generation, tRNA thiolation, protein urmylation and cyanide detoxification. Tissuespecific changes in MPST expression correlate with ageing and the development of metabolic disease. Deletion and overexpression experiments suggest that MPST c...
Source: Biological Chemistry - October 20, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Emerging roles for non-selenium containing ER-resident glutathione peroxidases in cell signaling and disease.
Authors: Buday K, Conrad M Abstract Maintenance of cellular redox control is pivotal for normal cellular functions and cell fate decisions including cell death. Among the key cellular redox systems in mammals, the glutathione peroxidase (GPX) family of proteins is the largest conferring multifaceted functions and affecting virtually all cellular processes. The endoplasmic reticulum (ER)- resident glutathione peroxidases, designated as GPX7 and GPX8, are the most recently added members of this family of enzymes. Recent studies have provided exciting insights how both enzymes support critical processes of the ER incl...
Source: Biological Chemistry - October 20, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

PCAT1 induced by transcription factor YY1 promotes cholangiocarcinoma proliferation, migration and invasion by sponging miR-216a-3p to up-regulate oncogene BCL3.
This study was designed to illustrate the function and role of PCAT1 in CCA. The relative expression was confirmed by RT-qPCR and western blot. The biological function of PCAT1 was evaluated by CCK8, EdU, colony formation, wound healing, transwell, and subcutaneous tumor formation assays. Protein levels of EMT markers were measured by western blot. The binding relationship was predicted by JASPAR and starBase. The binding of YY1 to PCAT1 promoter was assessed by ChIP and luciferase reporter. The binding capacity between miR- 216a-3p and PCAT1 as well as BCL3 was assessed by luciferase reporter and AGO2-RIP assays. In this ...
Source: Biological Chemistry - October 20, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Thioredoxin-dependent control balance the metabolic activities in tetrapyrrole biosynthesis.
We describe the impact of TRX-dependent control on the activity, stability and interactions of these enzymes, and assess its contribution to the provision of adequate supplies of metabolic intermediates in the face of diurnal and more rapid and transient changes in light levels and other environmental factors. PMID: 33068374 [PubMed - as supplied by publisher] (Source: Biological Chemistry)
Source: Biological Chemistry - October 20, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Glutaredoxins and iron-sulfur protein biogenesis at the interface of redox biology and iron metabolism.
Authors: Mühlenhoff U, Braymer JJ, Christ S, Rietzschel N, Uzarska MA, Weiler BD, Lill R Abstract The physiological roles of the intracellular iron and redox regulatory systems are intimately linked. Iron is an essential trace element for most organisms, yet elevated cellular iron levels are a potent generator and amplifier of reactive oxygen species and redox stress. Proteins binding iron or iron-sulfur (Fe/S) clusters, are particularly sensitive to oxidative damage and require protection from the cellular oxidative stress protection systems. In addition, key components of these systems, most prominently glut...
Source: Biological Chemistry - October 10, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Diversity of GPI-anchored fungal adhesins.
Authors: Essen LO, Vogt MS, Mösch HU Abstract Selective adhesion of fungal cells to one another and to foreign surfaces is fundamental for the development of multicellular growth forms and the successful colonization of substrates and host organisms. Accordingly, fungi possess diverse cell wall-associated adhesins, mostly large glycoproteins, which present N-terminal adhesion domains at the cell surface for ligand recognition and binding. In order to function as robust adhesins, these glycoproteins must be covalently linkedto the cell wall via C-terminal glycosylphosphatidylinositol (GPI) anchors by transglyco...
Source: Biological Chemistry - October 10, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Kill one or kill the many: interplay between mitophagy and apoptosis.
Authors: Wanderoy S, Hees JT, Klesse R, Edlich F, Harbauer AB Abstract Mitochondria are key players of cellular metabolism, Ca2+ homeostasis, and apoptosis. The functionality of mitochondria is tightly regulated, and dysfunctional mitochondria are removed via mitophagy, a specialized form of autophagy that is compromised in hereditary forms of Parkinson's disease. Through mitophagy, cells are able to cope with mitochondrial stress until the damage becomes too great, which leads to the activation of pro-apoptotic BCL-2 family proteins located on the outer mitochondrial membrane. Active pro-apoptotic BCL-2 proteins f...
Source: Biological Chemistry - October 10, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Expansion and inflammation of white adipose tissue - focusing on adipocyte progenitors.
Authors: Liu W, Li D, Cao H, Li H, Wang Y Abstract Adipose tissue is an important organ in our body, participating not only in energy metabolism but also immune regulation. It is broadly classified as white (WAT) and brown (BAT) adipose tissues. WAT is highly heterogeneous, composed of adipocytes, various immune, progenitor and stem cells, as well as the stromal vascular populations. The expansion and inflammation of WAT are hallmarks of obesity and play a causal role in the development of metabolic and cardiovascular diseases. The primary event triggering the inflammatory expansion of WAT remains unclear. The pres...
Source: Biological Chemistry - October 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Genomic insights into cyanobacterial protein translocation systems.
Authors: Russo DA, Zedler JAZ Abstract Cyanobacteria are ubiquitous oxygenic photosynthetic bacteria with a versatile metabolism that is highly dependent on effective protein targeting. Protein sorting in diderm bacteria is not trivial and, in cyanobacteria, even less so due to the presence of a complex membrane system: the outer membrane, the plasma membrane and the thylakoid membrane. In cyanobacteria, protein import into the thylakoids is essential for photosynthesis, export to the periplasm fulfils a multifunctional role in maintaining cell homeostasis, and secretion mediates motility, DNA uptake and environmen...
Source: Biological Chemistry - October 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Redox regulation in host-pathogen interactions: thiol switches and beyond.
Authors: Varatnitskaya M, Degrossoli A, Leichert LI Abstract Our organism is exposed to pathogens on a daily basis. Owing to this age-old interaction, both pathogen and host evolved strategies to cope with these encounters. Here, we focus on the consequences of the direct encounter of cells of the innate immune system with bacteria. First, we will discuss the bacterial strategies to counteract powerful reactive species. Our emphasis lies on the effects of hypochlorous acid (HOCl), arguably the most powerful oxidant produced inside the phagolysosome of professional phagocytes. We will highlight individual examples o...
Source: Biological Chemistry - October 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

RNA secondary structure dependence in METTL3-METTL14 mRNA methylation is modulated by the N-terminal domain of METTL3.
Authors: Meiser N, Mench N, Hengesbach M Abstract N6-methyladenosine (m6A) is the most abundant modification in mRNA. The core of the human N6-methyltransferase complex (MTC) is formed by a heterodimer consisting of METTL3 and METTL14, which specifically catalyzes m6A formation within a RRACH sequence context. Using recombinant proteins in a site-specific methylation assay that allows determination of quantitative methylation yields, our results show that this complex methylates its target RNAs not only sequence but also secondary structure dependent. Furthermore, we demonstrate the role of specific protein domains...
Source: Biological Chemistry - October 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Genetically encoded thiol redox-sensors in the zebrafish model: lessons for embryonic development and regeneration.
We describe how such observations have prompted insight into regulation and downstream effects of redox alterations during tissue differentiation, morphogenesis and regeneration. We also discuss the properties of the different sensors and their consequences for the interpretation of in vivo imaging results. Finally, we highlight open questions and additional research fields that may benefit from further application of such sensor systems in zebrafish models of development, regeneration and disease. PMID: 33021959 [PubMed - as supplied by publisher] (Source: Biological Chemistry)
Source: Biological Chemistry - October 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

The DEAH helicase DHX36 and its role in G-quadruplex-dependent processes.
Authors: Schult P, Paeschke K Abstract DHX36 is a member of the DExD/H box helicase family, which comprises a large number of proteins involved in various cellular functions. Recently, the function of DHX36 in the regulation of G-quadruplexes (G4s) was demonstrated. G4s are alternative nucleic acid structures, which influence many cellular pathways on a transcriptional and post-transcriptional level. In this review we provide an overview of the current knowledge about DHX36 structure, substrate specificity and mechanism of action based on the available models and crystal structures. Moreover, we outline its multipl...
Source: Biological Chemistry - October 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Detecting myocardial scar using electrocardiogram data and deep neural networks.
We present an artificial intelligence based approach - namely a deep learning model - for the prediction of myocardial scar based on an electrocardiogram and additional clinical parameters. The model was trained and evaluated by applying 6-fold cross-validation to a dataset of 12-lead electrocardiogram time series together with clinical parameters. The proposed model for predicting the presence of scar tissue achieved an area under the curve score, sensitivity, specificity, and accuracy of 0.89, 70.0, 84.3, and 78.0%, respectively. This promisingly high diagnostic precision of our electrocardiogram...
Source: Biological Chemistry - October 3, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Influence of monovalent metal ions on metal binding and catalytic activity of the 10-23 DNAzyme.
Authors: Rosenbach H, Borggräfe J, Victor J, Wuebben C, Schiemann O, Hoyer W, Steger G, Etzkorn M, Span I Abstract Deoxyribozymes (DNAzymes) are single-stranded DNA molecules that catalyze a broad range of chemical reactions. The 10-23 DNAzyme catalyzes the hydrolysis of RNA strands and can be designed to cleave essentially any target RNA, which makes it particularly interesting for therapeutic and biosensing applications. The activity of this DNAzyme in vitro is considerably higher than in cells, which was suggested to be a result of the low intracellular concentration of bioavailable divalent cations. While ...
Source: Biological Chemistry - September 30, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Multicellular and unicellular responses of microbial biofilms to stress.
Authors: Rode DKH, Singh PK, Drescher K Abstract Biofilms are a ubiquitous mode of microbial life and display an increased tolerance to different stresses. Inside biofilms, cells may experience both externally applied stresses and internal stresses that emerge as a result of growth in spatially structured communities. In this review, we discuss the spatial scales of different stresses in the context of biofilms, and if cells in biofilms respond to these stresses as a collection of individual cells, or if there are multicellular properties associated with the response. Understanding the organizational level of stres...
Source: Biological Chemistry - September 30, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Biochemical unity revisited: microbial central carbon metabolism holds new discoveries, multi-tasking pathways, and redundancies with a reason.
Authors: Borzyskowski LSV, Bernhardsgrütter I, Erb TJ Abstract For a long time, our understanding of metabolism has been dominated by the idea of biochemical unity, i.e., that the central reaction sequences in metabolism are universally conserved between all forms of life. However, biochemical research in the last decades has revealed a surprising diversity in the central carbon metabolism of different microorganisms. Here, we will embrace this biochemical diversity and explain how genetic redundancy and functional degeneracy cause the diversity observed in central metabolic pathways, such as glycolysis, autot...
Source: Biological Chemistry - September 30, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Cyclic di-GMP signaling controlling the free-living lifestyle of alpha-proteobacterial rhizobia.
Authors: Krol E, Schäper S, Becker A Abstract Cyclic-di-GMP (c-di-GMP) is a ubiquitous bacterial second messenger which has been associated with a motile to sessile lifestyle switch in many bacteria. Here, we review recent insights into c-di-GMP regulated processes related to environmental adaptations in alphaproteobacterial rhizobia, which are diazotrophic bacteria capable of fixing nitrogen in symbiosis with their leguminous host plants. The review centers on Sinorhizobium meliloti, which in the recent years was intensively studied for its c-di-GMP regulatory network. PMID: 32990642 [PubMed - as supplied...
Source: Biological Chemistry - September 30, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Thiol-based switching mechanisms of stress-sensing chaperones.
Authors: Ulrich K, Schwappach B, Jakob U Abstract Thiol-based redox switches evolved as efficient post-translational regulatory mechanisms that enable individual proteins to rapidly respond to sudden environmental changes. While some protein functions need to be switched off to save resources and avoid potentially error-prone processes, protective functions become essential and need to be switched on. In this review, we focus on thiol-based activation mechanisms of stress-sensing chaperones. Upon stress exposure, these chaperones convert into high affinity binding platforms for unfolding proteins and protect cells ...
Source: Biological Chemistry - September 30, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Generating asymmetry in a changing environment: cell cycle regulation in dimorphic alphaproteobacteria.
Authors: van Teeseling MCF, Thanbichler M Abstract While many bacteria divide by symmetric binary fission, some alphaproteobacteria have strikingly asymmetric cell cycles, producing offspring that differs significantly in their morphology and reproductive state. To establish this asymmetry, these species employ a complex cell cycle regulatory pathway based on two-component signaling cascades. At the center of this network is the essential DNA-binding response regulator CtrA, which acts as a transcription factor controlling numerous genes with cell cycle-relevant functions as well as a regulator of chromosome replic...
Source: Biological Chemistry - September 26, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Myricetin protects pancreatic β-cells from human islet amyloid polypeptide (hIAPP) induced cytotoxicity and restores islet function.
In this study, we attempt to identify the anti-amyloidogenic potential of Myricetin (MYR)- a polyphenolic flavanoid, commonly found in fruits (like Syzygium cumini). Our results from biophysical studies indicated that MYR supplementation inhibits hIAPP aggregation and disaggregates preformed fibrils into non-toxic species. This protection was accompanied by inhibition of oxidative stress, reduction in lipid peroxidation and the associated membrane damage and restoration of mitochondrial membrane potential in INS-1E cells. MYR supplementation also reversed the loss of functionality in hIAPP exposed pancreatic islets via res...
Source: Biological Chemistry - September 17, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Osteopontin enhances the migration of lung fibroblasts via upregulation of interleukin-6 through the extracellular signal-regulated kinase (ERK) pathway.
In this study, we investigated the effect of OPN on IL-6 secretion and on migration and proliferation of fibroblasts. Lung fibroblasts overexpressing exogenous OPN showed that OPN was linked to the enhancement of cell migration through increased IL-6 secretion via the extracellular signal-regulated kinase (ERK) pathway. These results suggest that OPN may exert its pro-fibrotic functions, such as enhancement of fibroblasts migration by cooperating with chemoattractant IL-6, and may be involved in enlargement of fibrotic foci. PMID: 32924371 [PubMed - in process] (Source: Biological Chemistry)
Source: Biological Chemistry - September 16, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

A progesterone receptor membrane component 1 antagonist induces large vesicles independent of progesterone receptor membrane component 1 expression.
Authors: Wang-Eckhardt L, Eckhardt M Abstract Treatment of different cell lines with progesterone receptor membrane component 1 (PGRMC1) antagonist AG-205 rapidly induces the formation of large vesicular structures that likely represent endosomes. Crispr/Cas9 was used to target the PGRMC1 and progesterone receptor membrane component 2 (PGRMC2) genes in CHO-K1 and HeLa. Unexpectedly, deficiency in one of these or both genes did not inhibit the formation of enlarged vesicles by AG-205, demonstrating additional molecular target(s) of this compound besides PGRMC1. Thus, AG-205 cannot be regarded as a PGRMC1-specific an...
Source: Biological Chemistry - September 16, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Spatial organisation enhances versatility and specificity in cyclic di-GMP signaling.
Authors: Kunz S, Graumann PL Abstract The second messenger cyclic di-GMP regulates a variety of processes in bacteria, many of which are centered around the decision whether to adopt a sessile or a motile life style. Regulatory circuits include pathogenicity, biofilm formation and motility in a wide variety of bacteria, and play a key role in cell cycle progression in Caulobacter crescentus. Interestingly, multiple, seemingly independent c-di-GMP pathways have been found in several species, where deletions of individual c-di-GMP synthetases (DGCs) or hydrolases (PDEs) have resulted in distinct phenotypes that would...
Source: Biological Chemistry - September 14, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Masters of change.
Authors: Bremer E Abstract No abstract available. PMID: 32918804 [PubMed - as supplied by publisher] (Source: Biological Chemistry)
Source: Biological Chemistry - September 14, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Phage-display reveals interaction of lipocalin allergen Can f 1 with a peptide resembling the antigen binding region of a human γδT- cell receptor.
Phage-display reveals interaction of lipocalin allergen Can f 1 with a peptide resembling the antigen binding region of a human γδT- cell receptor. Biol Chem. 2020 Sep 01;: Authors: Habeler M, Redl B Abstract Although some progress has been achieved in understanding certain aspects of the allergenic mechanism of animal lipocalins, they still remain largely enigmatic. One possibility to unravel this property is to investigate their interaction with components of the immune system. Since these components are highly complex we intended to use a high-throughput technology for this purpose. Ther...
Source: Biological Chemistry - September 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

An RNA-centric view on gut Bacteroidetes.
Authors: Ryan D, Prezza G, Westermann AJ Abstract Bacteria employ noncoding RNAs to maintain cellular physiology, adapt global gene expression to fluctuating environments, sense nutrients, coordinate their interaction with companion microbes and host cells, and protect themselves against bacteriophages. While bacterial RNA research has made fundamental contributions to biomedicine and biotechnology, the bulk of our knowledge of RNA biology stems from the study of a handful of aerobic model species. In comparison, RNA research is lagging in many medically relevant obligate anaerobic species, in particular the numero...
Source: Biological Chemistry - September 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Physiology of guanosine-based second messenger signaling in Bacillus subtilis.
Authors: Bange G, Bedrunka P Abstract The guanosine-based second messengers (p)ppGpp and c-di-GMP are key players of the physiological regulation of the Gram-positive model organism B. subtilis. Their regulatory spectrum ranges from key metabolic processes over motility to biofilm formation. Here we review our mechanistic knowledge on their synthesis and degradation in response to environmental and stress signals as well as what is known on their cellular effectors and targets. Moreover, we discuss open questions and our gaps in knowledge on these two important second messengers. PMID: 32881708 [PubMed - as sup...
Source: Biological Chemistry - September 7, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Human islet amyloid polypeptide (hIAPP) - a curse in type II diabetes mellitus: insights from structure and toxicity studies.
Authors: Bishoyi AK, Roham PH, Rachineni K, Save S, Hazari MA, Sharma S, Kumar A Abstract The human islet amyloid polypeptide (hIAPP) or amylin, a neuroendocrine peptide hormone, is known to misfold and form amyloidogenic aggregates that have been observed in the pancreas of 90% subjects with Type 2 Diabetes Mellitus (T2DM). Under normal physiological conditions, hIAPP is co-stored and co-secreted with insulin; however, under chronic hyperglycemic conditions associated with T2DM, the overexpression of hIAPP occurs has been associated with the formation of amyloid deposits; as well as the death and dysfunction of pa...
Source: Biological Chemistry - August 28, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Redox-dependent and independent effects of thioredoxin interacting protein.
Authors: Cao X, He W, Pang Y, Cao Y, Qin A Abstract Thioredoxin interacting protein (TXNIP) is an important physiological inhibitor of the thioredoxin (TXN) redox system in cells. Regulation of TXNIP expression and/or activity not only plays an important role in redox regulation but also exerts redox-independent physiological effects that exhibit direct pathophysiological consequences including elevated inflammatory response, aberrant glucose metabolism, cellular senescence and apoptosis, cellular immunity, and tumorigenesis. This review provides a brief overview of the current knowledge concerning the redox-depend...
Source: Biological Chemistry - August 28, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

ADAM8 affects glioblastoma progression by regulating osteopontin-mediated angiogenesis.
Authors: Li Y, Guo S, Zhao K, Conrad C, Driescher C, Rothbart V, Schlomann U, Guerreiro H, Bopp MH, König A, Carl B, Pagenstecher A, Nimsky C, Bartsch JW Abstract Glioblastoma multiforme (GBM) is the most aggressive type of brain cancer with a median survival of only 15 months. To complement standard treatments including surgery, radiation and chemotherapy, it is essential to understand the contribution of the GBM tumor microenvironment. Brain macrophages and microglia particularly contribute to tumor angiogenesis, a major hallmark of GBM. ADAM8, a metalloprotease-disintegrin strongly expressed in tumor cells ...
Source: Biological Chemistry - August 28, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Specific acclimations to phosphorus limitation in the marine diatom Phaeodactylum tricornutum.
Authors: Dell'Aquila G, Maier UG Abstract Phosphorus is a crucial element and diatoms, unicellular phototrophic organisms, evolved efficient strategies to handle limiting phosphorus concentrations in the oceans. In the last decade, several groups investigated the model diatom Phaeodactylum tricornutum concerning phosphate homeostasis mechanisms. Here, we summarize the actual status of knowledge by linking the available data sets, thereby indicating experimental limits but also future research directions. PMID: 32845857 [PubMed - as supplied by publisher] (Source: Biological Chemistry)
Source: Biological Chemistry - August 28, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Metabolism of non-growing bacteria.
Authors: Lempp M, Lubrano P, Bange G, Link H Abstract A main function of bacterial metabolism is to supply biomass building blocks and energy for growth. This seems to imply that metabolism is idle in non-growing bacteria. But how relevant is metabolism for the physiology of non-growing bacteria and how active is their metabolism? Here, we reviewed literature describing metabolism of non-growing bacteria in their natural environment, as well as in biotechnological and medical applications. We found that metabolism does play an important role during dormancy and that especially the demand for ATP determines metaboli...
Source: Biological Chemistry - August 28, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Galectin-3 is modulated in pancreatic cancer cells under hypoxia and nutrient deprivation.
Authors: da Silva Filho AF, Tavares LB, Pitta MGR, Beltrão EIC, Rêgo MJBM Abstract Pancreatic ductal adenocarcinoma is one of the most aggressive tumors with a microenvironment marked by hypoxia and starvation. Galectin-3 has been evaluated in solid tumors and seems to present both pro/anti-tumor effects. So, this study aims to characterize the expression of Galectin-3 from pancreatic tumor cells and analyze its influence for cell survive and motility in mimetic microenvironment. For this, cell cycle and cell death were accessed through flow cytometry. Characterization of inside and outside Galectin-3 ...
Source: Biological Chemistry - August 13, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

The ups and downs of ectoine: structural enzymology of a major microbial stress protectant and versatile nutrient.
Authors: Hermann L, Mais CN, Czech L, Smits SHJ, Bange G, Bremer E Abstract Ectoine and its derivative 5-hydroxyectoine are compatible solutes and chemical chaperones widely synthesized by Bacteria and some Archaea as cytoprotectants during osmotic stress and high- or low-growth temperature extremes. The function-preserving attributes of ectoines led to numerous biotechnological and biomedical applications and fostered the development of an industrial scale production process. Synthesis of ectoines requires the expenditure of considerable energetic and biosynthetic resources. Hence, microorganisms have developed wa...
Source: Biological Chemistry - August 13, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

The role of mitochondrial ATP synthase in cancer.
Authors: Galber C, Acosta MJ, Minervini G, Giorgio V Abstract The mitochondrial ATP synthase is a multi-subunit enzyme complex located in the inner mitochondrial membrane which is essential for oxidative phosphorylation under physiological conditions. In this review, we analyse the enzyme functions involved in cancer progression by dissecting specific conditions in which ATP synthase contributes to cancer development or metastasis. Moreover, we propose the role of ATP synthase in the formation of the permeability transition pore (PTP) as an additional mechanism which controls tumour cell death. We further describe ...
Source: Biological Chemistry - August 13, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Individual and combined effects of GIP and xenin on differentiation, glucose uptake and lipolysis in 3T3-L1 adipocytes.
In conclusion, GIP and xenin possess direct, comparable, lipogenic and lipolytic actions in 3T3-L1 adipocytes. However, effects on lipid metabolism are significantly diminished by combined administration. PMID: 32769216 [PubMed - as supplied by publisher] (Source: Biological Chemistry)
Source: Biological Chemistry - August 13, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Unexpected metabolic versatility among type II methanotrophs in the Alphaproteobacteria.
Authors: Hakobyan A, Liesack W Abstract Aerobic methane-oxidizing bacteria, or methanotrophs, play a crucial role in the global methane cycle. Their methane oxidation activity in various environmental settings has a great mitigation effect on global climate change. Alphaproteobacterial methanotrophs were among the first to be taxonomically characterized, nowadays unified in the Methylocystaceae and Beijerinckiaceae families. Originally thought to have an obligate growth requirement for methane and related one-carbon compounds as a source of carbon and energy, it was later shown that various alphaproteobacterial met...
Source: Biological Chemistry - August 13, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Biosynthesis and function of cell-surface polysaccharides in the social bacterium Myxococcus xanthus.
Authors: Pérez-Burgos M, Søgaard-Andersen L Abstract In bacteria, cell-surface polysaccharides fulfill important physiological functions, including interactions with the environment and other cells as well as protection from diverse stresses. The Gram-negative delta-proteobacterium Myxococcus xanthus is a model to study social behaviors in bacteria. M. xanthus synthesizes four cell-surface polysaccharides, i.e. exopolysaccharide (EPS), biosurfactant polysaccharide (BPS), spore coat polysaccharide, and O-antigen. Here, we describe recent progress in elucidating the three Wzx/Wzy-dependent pathways for ...
Source: Biological Chemistry - August 13, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Apoptosis inducing factor and mitochondrial NADH dehydrogenases: redox-controlled gear boxes to switch between mitochondrial biogenesis and cell death.
Authors: Herrmann JM, Riemer J Abstract The mitochondrial complex I serves as entry point for NADH into the electron transport chain. In animals, fungi and plants, additional NADH dehydrogenases carry out the same electron transfer reaction, however they do not pump protons. The apoptosis inducing factor (AIF, AIFM1 in humans) is a famous member of this group as it was the first pro-apoptotic protein identified that can induce caspase-independent cell death. Recent studies on AIFM1 and the NADH dehydrogenase Nde1 of baker's yeast revealed two independent and experimentally separable activities of this class of enzy...
Source: Biological Chemistry - August 13, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Hsp70-mediated quality control: should I stay or should I go?
Authors: Kohler V, Andréasson C Abstract Chaperones of the 70 kDa heat shock protein (Hsp70) superfamily are key components of the cellular proteostasis system. Together with its co-chaperones, Hsp70 forms proteostasis subsystems that antagonize protein damage during physiological and stress conditions. This function stems from highly regulated binding and release cycles of protein substrates, which results in a flow of unfolded, partially folded and misfolded species through the Hsp70 subsystem. Specific factors control how Hsp70 makes decisions regarding folding and degradation fates of the substrate ...
Source: Biological Chemistry - August 4, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Anti-amyloidogenic effect of artemin on α-synuclein.
The objective of this study was to investigate the anti-amyloidogenic effect of molecular chaperone artemin on α-synuclein. As the concentration of artemin was increased up to 4 μg/ml, a decrease in fibril formation of α-synuclein was observed using thioflavin T (ThT) fluorescence and congo red (CR) assay. Transmission electron microscopy (TEM) images also demonstrated a reduction in fibrils in the presence of artemin. The secondary structure of α-synuclein was similar to its native form prior to fibrillation when incubated with artemin. A cell-based assay has shown that artemin inhibits α-s...
Source: Biological Chemistry - July 18, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

DASH-type cryptochromes - solved and open questions.
Authors: Kiontke S, Göbel T, Brych A, Batschauer A Abstract DASH (Drosophila, Arabidopsis, Synechocystis, human)-type cryptochromes (cry-DASHs) form one subclade of the cryptochrome/photolyase family (CPF). CPF members are flavoproteins that act as DNA-repair enzymes (DNA-photolyases), or as UV-A/blue light photoreceptors (cryptochromes). In mammals, cryptochromes are essential components of the circadian clock feed-back loop. Cry-DASHs are present in almost all major taxa and were initially considered as photoreceptors. Later studies demonstrated DNA-repair activity that was, however, restricted to UV-lesions...
Source: Biological Chemistry - July 15, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

The impact of oxytocin on thiol/disulphide and malonyldialdehyde/glutathione homeostasis in stressed rats.
Authors: Korkmaz H, Önal D, Alışık M, Erel Ö, Pehlivanoğlu B Abstract We aimed to investigate the impact of oxytocin on serum thiol/disulphide and malonylyldialdehyde (MDA)/glutathione balance under acute and chronic stress exposure in rats. Animals were allocated into control (C), acute (AS) and chronic stress (CS) groups, then the groups subdivided as intranasal oxytocin or saline applied groups, randomly. Animals in the AS or CS groups were exposed to combined cold-immobilisation stress. Salivary corticosterone levels and elevated-plus maze (EPM) scores were used to assess stress response. Malonyly...
Source: Biological Chemistry - June 21, 2020 Category: Chemistry Tags: Biol Chem Source Type: research

Insights on intermolecular FMN-heme domain interaction and the role of linker length in cytochrome P450cin fusion proteins.
Authors: Belsare KD, Ruff AJ, Martinez R, Schwaneberg U Abstract Cytochrome P450s are an important group of enzymes catalyzing hydroxylation and epoxidations reactions. In this work we describe the characterization of the CinA-CinC fusion enzyme system of a previously reported P450 using genetically fused heme (CinA) and FMN (CinC) enzyme domains from Citrobacter braaki. We observed that mixing individually inactivated heme (-) with FMN (-) domain in the CinA-10aa linker- CinC fusion constructs results in recovered activity and the formation of (2S)-2β-hydroxy,1,8-cineole (174 μM), a similar amount when com...
Source: Biological Chemistry - June 20, 2020 Category: Chemistry Tags: Biol Chem Source Type: research