scholarly journals Targeting Nanodiamonds to the Nucleus in Yeast Cells

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1962
Author(s):  
Aryan Morita ◽  
Thamir Hamoh ◽  
Alina Sigaeva ◽  
Neda Norouzi ◽  
Andreas Nagl ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Cell Wall ◽  
Yeast Cells ◽  
Nuclear Targeting ◽  
Intracellular Location ◽  
Particle Uptake ◽  
Diamond Particles ◽  
Rigid Cell Wall ◽  
Nanoscale Sensing ◽  
First Time

Nanodiamonds are widely used for drug delivery, labelling or nanoscale sensing. For all these applications it is highly beneficial to have control over the intracellular location of the particles. For the first time, we have achieved targeting the nucleus of yeast cells. In terms of particle uptake, these cells are challenging due to their rigid cell wall. Thus, we used a spheroplasting protocol to remove the cell wall prior to uptake. To achieve nuclear targeting we used nanodiamonds, which were attached to antibodies. When using non-targeted particles, only 20% end up at the nucleus. In comparison, by using diamonds linked to antibodies, 70% of the diamond particles reach the nucleus.

Sites of Adsorption of the Bacteriophages T3 and T5 on the Wall of Escherichia Coli B.

1967 ◽  
Vol 25 ◽  
pp. 96-97
Author(s):  
Manfred E. Bayer
Keyword(s):  
Escherichia Coli ◽  
Cell Wall ◽  
Electron Microscope ◽  
Uranyl Acetate ◽  
E Coli ◽  
Receptor Sites ◽  
Rigid Cell Wall ◽  
Host Cell Surface ◽  
Bacterial Viruses ◽  
Escherichia Coli B

Bacterial viruses adsorb specifically to receptors on the host cell surface. Although the chemical composition of some of the cell wall receptors for bacteriophages of the T-series has been described and the number of receptor sites has been estimated to be 150 to 300 per E. coli cell, the localization of the sites on the bacterial wall has been unknown.When logarithmically growing cells of E. coli are transferred into a medium containing 20% sucrose, the cells plasmolize: the protoplast shrinks and becomes separated from the somewhat rigid cell wall. When these cells are fixed in 8% Formaldehyde, post-fixed in OsO4/uranyl acetate, embedded in Vestopal W, then cut in an ultramicrotome and observed with the electron microscope, the separation of protoplast and wall becomes clearly visible, (Fig. 1, 2). At a number of locations however, the protoplasmic membrane adheres to the wall even under the considerable pull of the shrinking protoplast. Thus numerous connecting bridges are maintained between protoplast and cell wall. Estimations of the total number of such wall/membrane associations yield a number of about 300 per cell.

Alkaliphilic species Euastrum lacustre (Charophyta, Zygnematophyceae), first record from Russia

2020 ◽  
Vol 54 (2) ◽  
pp. 313-320
Author(s):  
O. V. Anissimova
Keyword(s):  
Cell Wall ◽  
New Species ◽  
First Record ◽  
European Russia ◽  
Similar Species ◽  
Morphological Differences ◽  
First Time ◽  
Kursk Region

Euastrum lacustre is reported for Russia for the first time. This alcaliphilic species was found in the periphyton and plankton of three lakes in the Kursk Region (European Russia). A description of morphology, including the relief of cell wall, and habitats where this taxon is found are represented. LM and SEM microphotographs are provided. Morphological differences of E. lacustre from similar species are discussed. New species for region, namely Closterium aciculare, Cosmarium formosulum, C. granatum, C. pseudoinsigne, C. reniforme and Staurastrum pingue, are found in the samples together with E. lacustre.

scholarly journals Valorization of sugarcane bagasse by chemical pretreatment and enzyme mediated deconstruction

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Vihang S. Thite ◽  
Anuradha S. Nerurkar
Keyword(s):  
Cell Wall ◽  
Sugarcane Bagasse ◽  
Structural Changes ◽  
Enzymatic Saccharification ◽  
Dry Weight ◽  
Gravimetric Analysis ◽  
Chemical Pretreatment ◽  
Cell Wall Degrading Enzymes ◽  
First Time ◽  
Soluble Components

Abstract After chemical pretreatment, improved amenability of agrowaste biomass for enzymatic saccharification needs an understanding of the effect exerted by pretreatments on biomass for enzymatic deconstruction. In present studies, NaOH, NH4OH and H2SO4 pretreatments effectively changed visible morphology imparting distinct fibrous appearance to sugarcane bagasse (SCB). Filtrate analysis after NaOH, NH4OH and H2SO4 pretreatments yielded release of soluble reducing sugars (SRS) in range of ~0.17–0.44%, ~0.38–0.75% and ~2.9–8.4% respectively. Gravimetric analysis of pretreated SCB (PSCB) biomass also revealed dry weight loss in range of ~25.8–44.8%, ~11.1–16.0% and ~28.3–38.0% by the three pretreatments in the same order. Release of soluble components other than SRS, majorly reported to be soluble lignins, were observed highest for NaOH followed by H2SO4 and NH4OH pretreatments. Decrease or absence of peaks attributed to lignin and loosened fibrous appearance of biomass during FTIR and SEM studies respectively further corroborated with our observations of lignin removal. Application of commercial cellulase increased raw SCB saccharification from 1.93% to 38.84%, 25.56% and 9.61% after NaOH, H2SO4 and NH4OH pretreatments. Structural changes brought by cell wall degrading enzymes were first time shown visually confirming the cell wall disintegration under brightfield, darkfield and fluorescence microscopy. The microscopic evidence and saccharification results proved that the chemical treatment valorized the SCB by making it amenable for enzymatic saccharification.

scholarly journals Polyethylene Glycol Functionalized Graphene Oxide Nanoparticles Loaded with Nigella sativa Extract: A Smart Antibacterial Therapeutic Drug Delivery System

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3067
Author(s):  
Mustafa A. Jihad ◽  
Farah T. M. Noori ◽  
Majid S. Jabir ◽  
Salim Albukhaty ◽  
Faizah A. AlMalki ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Grain Size ◽  
Cell Wall ◽  
Graphene Oxide ◽  
Polyethylene Glycol ◽  
Nucleic Acid ◽  
Drug Delivery System ◽  
Delivery System ◽  
Nigella Sativa ◽  
Seed Extract

Flaky graphene oxide (GO) nanoparticles (NPs) were synthesized using Hummer’s method and then capped with polyethylene glycol (PEG) by an esterification reaction, then loaded with Nigella sativa (N. sativa) seed extract. Aiming to investigate their potential use as a smart drug delivery system against Staphylococcus aureus and Escherichia coli, the spectral and structural characteristics of GO-PEG NPs were comprehensively analyzed by XRD, AFM, TEM, FTIR, and UV- Vis. XRD patterns revealed that GO-PEG had different crystalline structures and defects, as well as a higher interlayer spacing. AFM results showed GONPs with the main grain size of 24.41 nm, while GONPs–PEG revealed graphene oxide aggregation with the main grain size of 287.04 nm after loading N. sativa seed extract, which was verified by TEM examination. A strong OH bond appeared in FTIR spectra. Furthermore, UV- Vis absorbance peaks at (275, 284, 324, and 327) nm seemed to be correlated with GONPs, GO–PEG, N. sativa seed extract, and GO –PEG- N. sativa extract. The drug delivery system was observed to destroy the bacteria by permeating the bacterial nucleic acid and cytoplasmic membrane, resulting in the loss of cell wall integrity, nucleic acid damage, and increased cell-wall permeability.

scholarly journals Nanodroplet-mediated catheter-directed sonothrombolysis of retracted blood clots

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Leela Goel ◽  
Huaiyu Wu ◽  
Bohua Zhang ◽  
Jinwook Kim ◽  
Paul A. Dayton ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Negative Pressure ◽  
Boiling Point ◽  
Clot Lysis ◽  
Control Group ◽  
Peak Negative Pressure ◽  
Blood Clots ◽  
Tissue Plasminogen ◽  
First Time

AbstractOne major challenge in current microbubble (MB) and tissue plasminogen activator (tPA)-mediated sonothrombolysis techniques is effectively treating retracted blood clots, owing to the high density and low porosity of retracted clots. Nanodroplets (NDs) have the potential to enhance retracted clot lysis owing to their small size and ability to penetrate into retracted clots to enhance drug delivery. For the first time, we demonstrate that a sub-megahertz, forward-viewing intravascular (FVI) transducer can be used for ND-mediated sonothrombolysis, in vitro. In this study, we determined the minimum peak negative pressure to induce cavitation with low-boiling point phase change nanodroplets and clot lysis. We then compared nanodroplet mediated sonothrombolysis to MB and tPA mediate techniques. The clot lysis as a percent mass decrease in retracted clots was 9 ± 8%, 9 ± 5%, 16 ± 5%, 14 ± 9%, 17 ± 9%, 30 ± 8%, and 40 ± 9% for the control group, tPA alone, tPA + US, MB + US, MB + tPA + US, ND + US, and ND + tPA + US groups, respectively. In retracted blood clots, combined ND- and tPA-mediated sonothrombolysis was able to significantly enhance retracted clot lysis compared with traditional MB and tPA-mediated sonothrombolysis techniques. Combined nanodroplet with tPA-mediated sonothrombolysis may provide a feasible strategy for safely treating retracted clots.

Synthesis and self-assembly behaviour of poly(Nα-Boc-l-tryptophan)-block-poly(ethylene glycol)-block-poly(Nα-Boc-l-tryptophan)

RSC Advances ◽  
2016 ◽  
Vol 6 (29) ◽  
pp. 24142-24153
Author(s):  
Andreea S. Voda ◽  
Kevin Magniez ◽  
Nisa V. Salim ◽  
Cynthia Wong ◽  
Qipeng Guo
Keyword(s):  
Drug Delivery ◽  
Ethylene Glycol ◽  
Self Assembly ◽  
Triblock Copolymers ◽  
Potential Drug ◽  
Poly Ethylene Glycol ◽  
Drug Delivery Applications ◽  
Poly Ethylene ◽  
First Time

We report for the first time the use of Nα-Boc-l-tryptophan for the synthesis of amphiphilic BAB triblock copolymers for potential drug delivery applications.

scholarly journals FRAP analysis of nucleocytoplasmic dynamics of the vitamin D receptor splice variant VDRB1: preferential targeting to nuclear speckles

2005 ◽  
Vol 388 (2) ◽  
pp. 509-514 ◽  
Author(s):  
Kathryn L. SUNN ◽  
John A. EISMAN ◽  
Edith M. GARDINER ◽  
David A. JANS
Keyword(s):  
Vitamin D ◽  
Vitamin D Receptor ◽  
Nuclear Import ◽  
Protein Import ◽  
Nucleocytoplasmic Transport ◽  
Nuclear Speckles ◽  
Nuclear Targeting ◽  
Nuclear Retention ◽  
First Time

Although the key components of the cellular nuclear transport machinery have largely been characterized through extensive efforts in recent years, in vivo measurements of the kinetics of nuclear protein import/export are patently few. The present study applies the approach of FRAP (fluorescence recovery after photobleaching) to examine the nucleocytoplasmic flux of a novel human VDRB1 (vitamin D receptor B1) isoform in living cells. Through an N-terminal extension containing a consensus nuclear targeting sequence, VDRB1 is capable of localizing in nuclear speckles adjacent to SC-35 (35 kDa splicing component)-containing speckles as well as in the nucleoplasm, dependent on ligand. Investigation of VDRB1 nucleocytoplasmic transport using FRAP indicates for the first time that the VDRB1 has a serum-modulated, active nuclear import mechanism. There is no evidence of an efficient, active export mechanism for VDRB1, probably as a result of nuclear retention. VDRB1 nuclear import in the absence of serum occurred more rapidly and to a greater extent to nuclear speckles compared with import to other nuclear sites. This preferential transport from the cytoplasm to and accumulation within nuclear speckles is consistent with the idea that the latter represent dynamic centres of VDRB1 interaction with other nuclear proteins. The results are consistent with the existence of specialized pathways to target proteins to nuclear subdomains.

scholarly journals MOF Decomposition and Introduction of Repairable Defects Using a Photodegradable Strut

2018 ◽  
Author(s):  
Jingjing Yan ◽  
John MacDonald ◽  
Shawn Burdette
Keyword(s):  
Drug Delivery ◽  
Porous Materials ◽  
New Method ◽  
Innovative Approach ◽  
Partial Decomposition ◽  
Multiple Defects ◽  
Potential Applications ◽  
Defect Repair ◽  
First Time ◽  
Interesting Area

Utilizing a photolabile ligand as MOF strut can make a framework undergo full or partial decomposition upon irradiation. For the first time, a nitrophenylacetate derivative has been incorporated into MOF as a backbone linker via PLSE method. The photo-induced decarboxylation of the NPDAC-MOF represents a novel way of degrading a MOF, which provides an innovative approach to formulating photoresponsive porous materials with potential applications in molecular release and drug delivery. When photoactive linker is mixed with non-photolabile linker via partial PLSE, the MOF structure can be retained after irradiation, but with the introduction of multiple defects, offering a new method to create vacancies in MOFs. Defect repair can be achieved by treatment with replacement ligands, the scope of which is an interesting area for developing customizable MOF contents.<br>

scholarly journals Physiological function of Flo11p domains and the particular role of amyloid core sequences of this adhesin in Saccharomyces cerevisiae

2021 ◽  
Author(s):  
Clara Bouyx ◽  
Marion Schiavone ◽  
Marie-Ange Teste ◽  
Etienne Dague ◽  
Nathalie Sieczkowski ◽  
...  
Keyword(s):  
Cell Wall ◽  
Amyloid Β ◽  
Surface Hydrophobicity ◽  
Yeast Cells ◽  
Invasive Growth ◽  
Specific Domain ◽  
A Genome ◽  
A Cell ◽  
Cellular Aggregates

Flocculins are a family of glycosylated proteins that provide yeast cells with several properties such as biofilm formation, flocculation, invasive growth or formation of velum. These proteins are similarly organised with a N-terminal (adhesion) domain, a stalk-like central B-domain with several repeats and a C-terminal sequence carrying a cell wall anchor site. They also contain amyloid β-aggregation-prone sequences whose functional role is still unclear. In this work, we show that Flo11p differs from other flocculins by the presence of unique amyloid-forming sequences, whose the number is critical in the formation of adhesion nanodomains under a physical shear force. Using a genome editing approach to identify the function of domains in Flo11p phenotypes, we show that the formation of cellular aggregates whose density increases with the number of amyloid sequences cannot be attributed to a specific domain of Flo11p. The same is true for plastic adhesion and surface hydrophobicity the intensity of which depends mainly on the abundance of Flo11p on the cell surface. In contrast, the N and C domains of Flo11p are essential for invasive growth in agar, whereas a reduction in the number of repeats of the B domain weakens this phenotype. However, expression of FLO11 alone is not sufficient to trigger this invasion phenotype. Finally, we show that this flocculin contributes to the integrity of the cell wall.

A comparison of the effects of several antifungal imidazole derivatives and polyenes on Candida albicans: an ultrastructural study by scanning electron microscopy

1982 ◽  
Vol 28 (10) ◽  
pp. 1119-1126 ◽  
Author(s):  
M. Bastide ◽  
S. Jouvert ◽  
J.-M. Bastide
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Candida Albicans ◽  
Cytoplasmic Membrane ◽  
Electron Microscopic Examination ◽  
Yeast Cells ◽  
Electron Microscopic ◽  
Imidazole Derivatives ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

The early events in the interaction of two polyene (amphotericin B and nystatin) and five imidazole (clotrimazole, ketoconazole, miconazole, isoconazole, and econazole) antimycotics used at fungicidal concentrations with the surface of Candida albicans were studied by scanning electron microscopic examination of treated intact young yeast cells, treated spheroplasts, and spheroplasts liberated from treated young yeast cells. In all cases, treatment lasted 2 h. The polyenes passed through the yeast cell wall and interacted with the cytoplasmic membrane causing the spheroplasts to lose their characteristic spheric form and to liberate their contents. Clotrimazole caused the formation of numerous circular openings in the cytoplasmic membrane, but only when the agent was used to treat spheroplasts directly. Ketoconazole, miconazole, isoconazole, and econazole interacted with the cell wall causing formation of convolutions and wrinkles. The three imidazole derivatives that are structurally closely related, miconazole, isoconazole, and econazole, inhibited the enzyme-catalyzed release of spheroplasts from young yeast cells.

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