Read by QxMD icon Read

Membrane contact

Keigo Kumagai, Cherilyn A Elwell, Shuji Ando, Joanne N Engel, Kentaro Hanada
Chlamydia trachomatis is an obligate intracellular bacterium that replicates within a membranous compartment, the inclusion, in host cells. Its intracellular life cycle requires host sphingolipids, which are in part acquired through the ER-Golgi localized ceramide transport protein (CERT). The Chlamydia-encoded inclusion membrane protein IncD is composed of two closely linked long hydrophobic domains with their N- and C-termini exposed to the host cytosol. IncD binds directly to the pleckstrin homology (PH) domain of CERT, likely redirecting ceramide to the inclusion...
October 9, 2018: Biochemical and Biophysical Research Communications
Wang Wen-Qiong, Zhang Xiao-Feng
The process of microbial transglutaminase (TG) covalent immobilization on an ultrafiltration membrane surface, the optimum immobilization conditions and the characteristics of the enzymatic membrane in a reactor were investigated. The process of TG immobilization on polyethersulfone (PES) membrane surfaces was analyzed by Fourier transform infrared and X-ray photoelectron spectroscopy. The optimal condition for TG immobilization was in pH 5.0 phosphate buffer containing TG (20 U/mL). The immobilized TG had a high affinity for the substrate according to the kinetic parameters and retained 50% activity until the twentieth day...
October 9, 2018: Journal of Biotechnology
Arlo Adams, Aarati Sriram, A Wayne Vogl
Sertoli cells of the mammalian seminiferous epithelium form unique subcellular actin-related structures at intercellular junctions. The appearance of these so called "tubulobulbar complexes" (TBCs) precedes both sperm release at the apex of the epithelium and the movement of early spermatogenic cells out of the spermatogonial stem cell niche at the base of the epithelium. TBCs are considered to be part of the mechanism of junction endocytosis by Sertoli cells. The structures contain junction proteins and morphologically identifiable junctions, and are associated with markers of endocytosis...
October 12, 2018: Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
Nannan Zhang, Lina Yue, Yajie Xie, Oluwarotimi William Samuel, Olatunji Mumini Omisore, Weihua Pei, Xiao Xing, Chuang Lin, Yudong Zheng, Lei Wang
We propose a flexible, dry, and antibacterial electrode with a low and stable skin electrode contact impedance for bio-potential signal monitoring. We fabricated a bacterial cellulose/polyaniline/AgNO3 nanocomposite membrane (BC/PANI/AgNO3 ) and used it for bio-potential signal monitoring. The bacterial cellulose (BC) provides a 3-D nanoporous network structure, and it was used as a substrate material in the BC/PANI/AgNO3 nanocomposite membrane. Polyaniline (PANI) and AgNO3 , acting as conductive and antibacterial components, respectively, were polymerized and deposited on the surfaces of BC nanofibers to produce uniform thin film membrane with flexible, antibacterial, and conductive properties...
2018: IEEE Journal of Translational Engineering in Health and Medicine
Hirohito Tsurumaru, Naofumi Ito, Koji Mori, Satoshi Wakai, Taku Uchiyama, Takao Iino, Akira Hosoyama, Hanako Ataku, Keiko Nishijima, Miyako Mise, Ai Shimizu, Takeshi Harada, Hiroshi Horikawa, Natsuko Ichikawa, Tomohiro Sekigawa, Koji Jinno, Satoshi Tanikawa, Jun Yamazaki, Kazumi Sasaki, Syuji Yamazaki, Nobuyuki Fujita, Shigeaki Harayama
Certain methanogens deteriorate steel surfaces through a process called microbiologically influenced corrosion (MIC). However, the mechanisms of MIC, whereby methanogens oxidize zerovalent iron (Fe0 ), are largely unknown. In this study, Fe0 -corroding Methanococcus maripaludis strain OS7 and its derivative (strain OS7mut1) defective in Fe0 -corroding activity were isolated. Genomic analysis of these strains demonstrated that the strain OS7mut1 contained a 12-kb chromosomal deletion. The deleted region, termed "MIC island", encoded the genes for the large and small subunits of a [NiFe] hydrogenase, the TatA/TatC genes necessary for the secretion of the [NiFe] hydrogenase, and a gene for the hydrogenase maturation protease...
October 11, 2018: Scientific Reports
Satomi Funahashi, Yasumasa Okazaki, Takahiro Nishiyama, Hidekazu Ohyoshi, Hiroyuki Yasui, Kazuki Nishida, Shigeyuki Matsui, Shinya Toyokuni
Exposure to asbestos fiber is central to mesothelial carcinogenesis, for which iron overload in or near mesothelial cells is a key pathogenic mechanism. Alternatively, iron chelation therapy with deferasirox or regular phlebotomy was significantly preventive against crocidolite-induced mesothelial carcinogenesis in rats. However, the role of iron transporters during asbestos-induced carcinogenesis remains elusive. Here, we studied the role of divalent metal transporter 1 (DMT1; Slc11a2), which is a Fe(II) transporter, that is present not only on the apical plasma membrane of duodenal cells but also on the lysosomal membrane of every cell, in crocidolite-induced mesothelial carcinogenesis using DMT1 transgenic (DMT1Tg) mice...
October 12, 2018: Free Radical Research
Emilio Siendones, Manuel Ballesteros, Plácido Navas
Cytochrome b5 reductase 3 (CYB5R3) is a membrane-bound NADH-dependent redox enzyme anchored to the mitochondrial outer membrane, endoplasmic reticulum, and plasma membrane. Recessive hereditary methaemoglobinaemia (RHM) type II is caused by CYB5R3 deficiency and is an incurable disease characterized by severe encephalopathy with mental retardation, microcephaly, generalized dystonia, and movement disorders. Currently, the etiology of type II RHM is poorly understood and there is no treatment for encephalopathy associated with this disease...
October 10, 2018: Journal of Clinical Medicine
Anna P Florentino, Inês A C Pereira, Sjef Boeren, Michael van den Born, Alfons J M Stams, Irene Sánchez-Andrea
Many questions regarding proteins involved in microbial sulfur metabolism remain unsolved. For sulfur respiration at low pH, the terminal electron acceptor is still unclear. Desulfurella amilsii is a sulfur-reducing bacterium that respires elemental sulfur (S0 ) or thiosulfate, and grows by S0 disproportionation. Due to its versatility, comparative studies on D. amilsii may shed light on microbial sulfur metabolism. Requirement of physical contact between cells and S0 was analyzed. Sulfide production decreased by around 50% when S0 was trapped in dialysis membranes, suggesting that contact between cells and S0 is beneficial, but not strictly needed...
October 11, 2018: Environmental Microbiology
Neil Ashley, Djamila Ouaret, Walter F Bodmer
Colonic epithelial cells are highly polarised with a lumen-facing apical membrane, termed the brush border, and a basal membrane in contact with the underlying extracellular matrix (ECM). This polarity is often maintained in cancer tissue in the form of neoplastic glands and has prognostic value. We compared the cellular polarity of several ex vivo spheroid colonic cancer cultures with their parental tumours and found that those grown as non-attached colonies exhibited apical brush border proteins on their outer cellular membranes...
October 10, 2018: Journal of Pathology
Xiaoying Qiao, Chunyan Yang, Qian Zhang, Shengke Yang, Yangyang Chen, Dan Zhang, Xiaoyu Yuan, Wenke Wang, Yaqian Zhao
In order to prepare parabolic superhydrophobic materials, copper meshes were used as the substrate and ultrasonic etching and oxidative corrosion were carried out with FeCl₃ solution and H₂O₂ solution, respectively, and then the surface was modified with stearic acid (SA). The topological structure and surface wettability of the prepared mesh were characterized by fluorescence microscope, scanning electron microscopy and contact angle measurement. Finally, the as-prepared copper meshes were applied to oil-water separation...
October 9, 2018: Materials
Jie Li, XuZhao Zhai, Chengchao Ding, Yali Liu, Qingli Dong, Dongpo Xu, Xiang Wang, Jingxuan Qiu, Qi Zhang, Jing Pan, Qing Liu
Hybridoma screening is a key step for the successful generation of high-affinity analyte-specific monoclonal antibodies (MAbs). This work presents an innovative screening method, known as a bacterial macroarray, generated by contact printing of hybridoma cell supernatant samples on a nitrocellulose (NC) membrane initially coated with fluorescein isothiocyanate (FITC)-labeled bacteria. Given that bacterial fixation will be influenced by complex bacterial surface structures, we selected both gram-positive bacteria ( Staphylococcus aureus and Listeria monocytogenes) and gram-negative bacteria ( Escherichia coli O157:H7 and Cronobacter sakazakii) to optimize the fixation conditions for binding to the NC membrane, such as the aperture of the NC membrane, the concentration of bacteria, the dosage of glycerin in the spotting buffer, and the fixation time and temperature...
October 10, 2018: SLAS Discovery
Dwiyantari Widyaningrum, Daisuke Iida, Yuma Tanabe, Yasuko Hayashi, Sari Dewi Kurniasih, Takeshi Ohama
Nanoparticles have unique properties that make them attractive for use in industrial and medical technology industries but can also be harmful to living organisms, making an understanding of their molecular mechanisms of action essential. We examined the effect of three different sized poly(isobutyl-cyanoacrylate) nanoparticles (iBCA-NPs) on the unicellular green alga Chlamydomonas reinhardtii. We found that exposure to iBCA-NPs immediately caused C. reinhardtii to display abnormal swimming behaviors. Furthermore, after one hour, most of the cells had stopped swimming and 10-30% of cells were stained with trypan blue, suggesting that these cells had severely impaired plasma membranes...
October 10, 2018: Journal of Phycology
Georg Krainer, Antoine Treff, Andreas Hartmann, Tracy A Stone, Mathias Schenkel, Sandro Keller, Charles M Deber, Michael Schlierf
Our meagre understanding of CFTR misfolding and its reversal by small-molecule correctors hampers the development of mechanism-based therapies of cystic fibrosis. Here we exploit a helical-hairpin construct-the simplest proxy of membrane-protein tertiary contacts-containing CFTR's transmembrane helices 3 and 4 and its corresponding disease phenotypic mutant V232D to gain molecular-level insights into CFTR misfolding and drug rescue by the corrector Lumacaftor. Using a single-molecule FRET approach to study hairpin conformations in lipid bilayers, we find that the wild-type hairpin is well folded, whereas the V232D mutant assumes an open conformation in bilayer thicknesses mimicking the endoplasmic reticulum...
2018: Communications biology
Violaine Dubois, Albertus Viljoen, Laura Laencina, Vincent Le Moigne, Audrey Bernut, Faustine Dubar, Mickaël Blaise, Jean-Louis Gaillard, Yann Guérardel, Laurent Kremer, Jean-Louis Herrmann, Fabienne Girard-Misguich
Mycobacterium abscessus is a peculiar rapid-growing Mycobacterium (RGM) capable of surviving within eukaryotic cells thanks to an arsenal of virulence genes also found in slow-growing mycobacteria (SGM), such as Mycobacterium tuberculosis A screen based on the intracellular survival in amoebae and macrophages (MΦ) of an M. abscessus transposon mutant library revealed the important role of MAB_0855, a yet uncharacterized Mycobacterial membrane protein Large (MmpL). Large-scale comparisons with SGM and RGM genomes uncovered MmpL12 proteins as putative orthologs of MAB_0855 and a locus-scale synteny between the MAB_0855 and Mycobacterium chelonae mmpL8 loci...
October 9, 2018: Proceedings of the National Academy of Sciences of the United States of America
Tanya L Arbogast, Brian C J Moore, Sunil Puria, Drew Dundas, Judith Brimacombe, Brent Edwards, Suzanne Carr Levy
OBJECTIVES: The objective of this study was to test the ability to achieve, maintain, and subjectively benefit from extended high-frequency amplification in a real-world use scenario, with a device that restores audibility for frequencies up to 10 kHz. DESIGN: A total of 78 participants (149 ears) with mild to moderately-severe sensorineural hearing loss completed one of two studies conducted across eight clinical sites. Participants were fitted with a light-driven contact hearing aid (the Earlens system) that directly drives the tympanic membrane, allowing extended high-frequency output and amplification with minimal acoustic feedback...
October 8, 2018: Ear and Hearing
Annie Cristhine Moraes Sousa-Squiavinato, Murilo Ramos Rocha, Pedro Barcellos-de-Souza, Waldemir Fernandes Souza, Jose Andres Morgado-Diaz
Colorectal cancer (CRC) is frequently a lethal disease because of metastasis. Actin cytoskeletal rearrangement is an essential step in cell migration during activation of the epithelial-mesenchymal transition (EMT) program, which is associated with metastatic properties of cancer cells. Cofilin-1 protein modulates actin dynamics by promoting actin treadmilling, thereby driving membrane protrusion and cell migration and invasion. However, the role of cofilin-1 during EMT in CRC is unknown. Here, we show that cofilin-1 and p-cofilin-1 have distinct subcellular distribution in EMT cells, as determined by super-resolution microscopy images, indicating distinct roles in different areas of cells...
October 5, 2018: Biochimica et biophysica acta. Molecular cell research
L Jelti, M Alorini, C Boivin, P Courville, X Balguerie, A Bonmarchand, E Angot
BACKGROUND: Angiomatoid fibrous histiocytoma (AFH) is a slowly progressing rare soft-tissue tumour of moderate malignant potential. It is most commonly seen in children and young adults. Clinically, the lesion is easily confused with a haematoma or soft-tissue haemangioma, and the radiological aspects are not specific. PATIENTS AND METHODS: A 16-year-old male patient presented with a nodular lesion situated very close to the right radial artery, vein and nerve and which had been developing for several years...
October 4, 2018: Annales de Dermatologie et de Vénéréologie
Victor V Lemeshko
Glycolysis plays a key role in brain energy metabolism. The initial and rate-limiting step of brain glycolysis is catalyzed mainly by hexokinase I (HKI), the majority of which is bound to the mitochondrial outer membrane (MOM), mostly through the mitochondrial inter-membrane contact sites formed by the voltage-dependent anion channel (VDAC, outer membrane) and the adenine nucleotide translocator (ANT, inner membrane). Earlier, we proposed a mechanism for the generation of the mitochondrial outer membrane potential (OMP) as a result of partial application of the inner membrane potential (IMP) to MOM through the electrogenic ANT-VDAC-HK inter-membrane contact sites...
October 4, 2018: Biochimica et biophysica acta. Biomembranes
Emily N Abada, Benjamin J Feinberg, Shuvo Roy
While extracorporeal membrane oxygenation (ECMO) is a valuable therapy for patients with lung or heart failure, clinical use of ECMO remains limited due to hemocompatibility concerns with pro-coagulatory hollow fiber membrane geometries. Previously, we demonstrated the feasibility of silicon nanopore (SNM) and micropore (SμM) membranes for transport between two liquid-phase compartments in blood-contacting devices. Herein, we investigate various pore sizes of SNM and SμM membranes - alone or with a polydimethylsiloxane (PDMS) protective coating - for parameters that determine suitability for gas exchange...
October 5, 2018: Biomedical Microdevices
Alena Koukalová, Šárka Pokorná, Aimee L Boyle, Nestor Lopez Mora, Alexander Kros, Martin Hof, Radek Šachl
A model system for membrane fusion, inspired by SNARE proteins and based on two complementary lipopeptides CPnE4 and CPnK4, has been recently developed. It consists of cholesterol (C), a poly(ethylene glycol) linker (Pn) and either a cationic peptide K4 (KIAALKE)4 or an anionic peptide E4 (EIAALEK)4. In this paper, fluorescence spectroscopy is used to decipher distinct but complementary roles of these lipopeptides during early stages of membrane fusion. Molecular evidence is provided that different distances of E4 in CPnE4 and K4 in CPnK4 from the bilayer represent an important mechanism, which enables fusion...
October 5, 2018: Nanoscale
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"