The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

BODIPY-based fluorescent liposomes with sesquiterpene lactone trilobolide

• Ludmila Škorpilová,
• Silvie Rimpelová,
• Michal Jurášek,
• Miloš Buděšínský,
• Jana Lokajová,
• Roman Effenberg,
• Petr Slepička,
• Tomáš Ruml,
• Eva Kmoníčková,
• Pavel B. Drašar and
• Zdeněk Wimmer

Beilstein J. Org. Chem. 2017, 13, 1316–1324, doi:10.3762/bjoc.13.128

• construct 6 and its liposomal formulation, both of which showed immunomodulatory properties in primary rat macrophages. The uptake and intracellular distribution of construct 6 and its liposomal formulation was monitored by means of live-cell fluorescence microscopy in two cancer cell lines. The

• potency of the fluorescent construct Tb-ChL and BODIPY and its liposome derivative to enter cancer cells was tested by live-cell fluorescence microscopy using two human cell line models: cells were derived from osteosarcoma (U-2 OS) and cervical carcinoma (HeLa). Inside U-2 OS cells, construct 6 was

• represents the arithmetic average of the deviations from the centre plane of the sample. Panel of images from live-cell fluorescence microscopy: intracellular localization of construct 6 in U-2 OS cells after 48 h of incubation: A) 200 nM; C) 500 nM concentration of construct 6; B) and D) merges of A and C

Correlation of surface pressure and hue of planarizable push–pull chromophores at the air/water interface

• Frederik Neuhaus,
• Fabio Zobi,
• Gerald Brezesinski,
• Marta Dal Molin,
• Stefan Matile and
• Andreas Zumbuehl

Beilstein J. Org. Chem. 2017, 13, 1099–1105, doi:10.3762/bjoc.13.109

• using fluorescence microscopy, grazing-incidence angle X-ray diffraction, and infrared reflection–absorption spectroscopy. An increase of the lateral membrane pressure leads to a well-packed layer of the ‘flipper’ mechanophores and a clear change in hue above 18 mN/m. The fluorescent probes had no

Expression, purification and structural analysis of functional GABA transporter 1 using the baculovirus expression system

• Jing Hu,
• Chris Weise,
• Christoph Böttcher,
• Hua Fan and
• Jian Yin

Beilstein J. Org. Chem. 2017, 13, 874–882, doi:10.3762/bjoc.13.88

• polyclonal antiserum. Subsequently, the blots were incubated with horseradish peroxidase-conjugated anti-rabbit antibody (IgG) (Dako Cytomation) and then visualized using amino ethylcarbazole (AEC) and substrate buffer (Calbiochem). Flow cytometry and fluorescence microscopy Sf9 cells were observed after 3

• -day infection by flow cytometry and fluorescence microscopy to determine the cell surface expression of the GAT1/GFP fusion proteins. MALDI mass fingerprinting Using MALDI–TOF MS, protein fragments with blocked N-termini or that are available in limited concentrations can be easily analyzed. The MALDI

• recorded according to the low-dose protocol of the microscope at a primary magnification of 62, 000×. Expression of GFP-tagged GAT1 in infected insect cells. (A) Flow cytometry analysis of GAT1/GFP in Sf9 cells. (B) Fluorescence microscopy of infected Sf9 cells. The GFP fluorescence in the GAT1/GFP fusion

Membrane properties of hydroxycholesterols related to the brain cholesterol metabolism

• Malte Hilsch,
• Ivan Haralampiev,
• Peter Müller,
• Daniel Huster and
• Holger A. Scheidt

Beilstein J. Org. Chem. 2017, 13, 720–727, doi:10.3762/bjoc.13.71

• of several hydroxycholesterols with those of cholesterol using 2H NMR spectroscopy, a membrane permeability assay, and fluorescence microscopy experiments. It is shown that hydroxycholesterols do not exert the unique impact on membrane properties characteristic for cholesterol with regard to the

• properties such as lipid chain packing, membrane permeability, and membrane domain formation is investigated. These parameters are compared with those obtained for cholesterol by using various biophysical techniques such as NMR and fluorescence spectroscopy as well as fluorescence microscopy. Results Lipid

• of the vesicles. The fluorescence microscopy images of cholesterol-containing GUVs show large membrane regions of low and of high fluorescence intensity, representing the lo and ld phase, respectively (Figure 4A). Note, that the vesicle shown in Figure 4A probably forms another dark lo domain on the

Fluorescent carbon dots from mono- and polysaccharides: synthesis, properties and applications

• Stephen Hill and
• M. Carmen Galan

Beilstein J. Org. Chem. 2017, 13, 675–693, doi:10.3762/bjoc.13.67

• labelled with either TAT (a cell-penetrating peptide), or folate and then incubated with HeLa cells. Fluorescence microscopy images confirmed that incubation times of 3–6 hours were adequate to allow for CD labelling of the cells. Further toxicity assays indicated that concentrations of up to 200 μg/mL

• concentrations of 100 μg/mL, while slight levels of toxicity were detected at concentrations of up to 1000 μg/mL. Fluorescence microscopy analysis of HeLa cells treated with CDs at 100 μg/mL for 24 h showed cell internalisation as monitored by their multicolour emissive properties, in addition LCSM confirmed

Isoxazole derivatives as new nitric oxide elicitors in plants

• Anca Oancea,
• Emilian Georgescu,
• Florentina Georgescu,
• Alina Nicolescu,
• Elena Iulia Oprita,
• Catalina Tudora,
• Lucian Vladulescu,
• Marius-Constantin Vladulescu,
• Florin Oancea and
• Calin Deleanu

Beilstein J. Org. Chem. 2017, 13, 659–664, doi:10.3762/bjoc.13.65

• of both NO and ROS was proven by fluorescence microscopy using specific fluorescence indicators that help to exactly define the sites of generation. We used Arabidopsis thaliana wild type seeds, cultivated for six weeks in laboratory in Arasystem [60]. Arabidopsis thaliana was selected as model

• 50 μg/mL, respectively) and collected after 24 h. Collected leaves were washed with distilled water and incubated with the specific fluorescence indicator for histochemical analysis of ROS and NO by fluorescence microscopy. Arabidopsis leaves untreated with inductor suspensions have been used as

• diacetate), a non-fluorescent compound, which reacts with NO to form a fluorescent benzotriazole and does not react with any ROS [64][65][66][67]. Fluorescence microscopy images of all 3,5-disubstituted isoxazoles-treated Arabidopsis leaves showed a pronounced presence of ROS at both concentrations of

Versatile synthesis of end-reactive polyrotaxanes applicable to fabrication of supramolecular biomaterials

• Atsushi Tamura,
• Asato Tonegawa,
• Yoshinori Arisaka and
• Nobuhiko Yui

Beilstein J. Org. Chem. 2016, 12, 2883–2892, doi:10.3762/bjoc.12.287

• installation of two fluorescent molecules at the terminals of the PRX is sufficient for detecting the intracellular trafficking and biodistribution of PRXs by fluorescence microscopy [38]. In addition, the terminal azide groups in the PRXs can act as installation moieties for magnetic resonance imaging (MRI

A self-assembled cyclodextrin nanocarrier for photoreactive squaraine

• Ulrike Kauscher and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2016, 12, 2535–2542, doi:10.3762/bjoc.12.248

• amphiphilic cyclodextrins were formed by electroformation [35]. The obtained vesicles have a size of several micrometers and are thus directly visible by fluorescence microscopy. AdSq were added to a solution of the GUVs and immobilization of the molecules was examined with confocal fluorescence spectroscopy

• . The images taken show GUVs with a red luminescent membrane due to the squaraines bound to the GUV surface (Figure 4). Thus, fluorescence microscopy provided direct evidence for the immobilization of AdSq on the CDV. After the immobilization of AdSq on the surface of CDV was demonstrated, we

• –guest interactions. Confocal fluorescence microscopy of giant unilamellar vesicles (GUVs) of amphiphilic cyclodextrins with AdSq on their outer surface. Top: Absorption spectra at different time points during irradiation of a CDV solution with AdSq immobilised on the vesicle surface. Bottom: DLS spectra

Practical synthetic strategies towards lipophilic 6-iodotetrahydroquinolines and -dihydroquinolines

• David R. Chisholm,
• Garr-Layy Zhou,
• Ehmke Pohl,
• Roy Valentine and
• Andrew Whiting

Beilstein J. Org. Chem. 2016, 12, 1851–1862, doi:10.3762/bjoc.12.174

• range from the classic Skraup–Doebner–von Miller syntheses, to catalytic and asymmetric methods [2][3][4]. We required a straightforward synthesis of THQs and DHQs for the synthesis of a library of biocompatible fluorophores with the potential to be used in fluorescence microscopy applications. The

Smart molecules for imaging, sensing and health (SMITH)

• Bradley D. Smith

Beilstein J. Org. Chem. 2015, 11, 2540–2548, doi:10.3762/bjoc.11.274

• conjugated with targeting ligands, and bioimaging studies have shown that they enable fluorescence microscopy and mesoscale imaging of diverse biomedical targets such as tumors, infection, bone, cell death, and brown adipose tissue [37][38] (Figure 3). Several of these molecular probes are commercially

• selectively recognize the anionic head group of phosphatidylserine [12]. Furthermore, binding strength is amplified by electrostatic attraction of the cationic receptor to the apoptotic cell membrane with a negative surface potential. We developed a family of fluorescent ZnDPA probes for fluorescence

• microscopy and flow cytometry methods for preclinical research [13][14][15][16] (Figure 2). Many of these fluorescent probes are used as imaging reagents to quantify the level of cell death in a range of biomedical samples [17]. We also developed some nuclear isotopic labeled probes for in vivo imaging of

Preparation of Pickering emulsions through interfacial adsorption by soft cyclodextrin nanogels

• Shintaro Kawano,
• Toshiyuki Kida,
• Mitsuru Akashi,
• Hirofumi Sato,
• Motohiro Shizuma and
• Daisuke Ono

Beilstein J. Org. Chem. 2015, 11, 2355–2364, doi:10.3762/bjoc.11.257

• dilution with water, the emulsion was observed using fluorescence microscopy. Similar oil droplets were observed by optical (Figure 6A) and fluorescence (Figure 6B) microscopy without and with a filter set, respectively. The CD nanogels (green) are concentrated at the surface of the oil droplet, confirming

Profluorescent substrates for the screening of olefin metathesis catalysts

• Raphael Reuter and
• Thomas R. Ward

Beilstein J. Org. Chem. 2015, 11, 1886–1892, doi:10.3762/bjoc.11.203

• and fluorescence showed good agreement. These profluorescent substrates could be prototypes for more complex structures that could find applications in ring-closing metathesis for biological applications by fluorescence microscopy. Experimental General Methods: The 1H and 13C NMR spectra were recorded

Terminal lipophilization of a unique DNA dodecamer by various nucleolipid headgroups: Their incorporation into artificial lipid bilayers and hydrodynamic properties

• Emma Werz and
• Helmut Rosemeyer

Beilstein J. Org. Chem. 2015, 11, 913–929, doi:10.3762/bjoc.11.103

• determination of the bilayer brightness using fluorescence microscopy [8]. In the following, we describe the insertion of six unique single-stranded DNA dodecamers carrying different nucleolipid head groups as well as cyanine-5 (Cy5) at the 5’-(n−1) position in artificial lipid bilayers. In this case we varied

• brightness was given either in kHz or it was normalized (0–100%). The z-direction scan was performed in 5 min intervals (see below). After the incubation steps, the cis compartment was perfused repeatedly for 30 s (1.1 mL/min, each), and the bilayer was inspected by confocal fluorescence microscopy. Each

Regulation of integrin and growth factor signaling in biomaterials for osteodifferentiation

• Qiang Wei,
• Theresa L. M. Pohl,
• Anja Seckinger,
• Joachim P. Spatz and
• Elisabetta A. Cavalcanti-Adam

Beilstein J. Org. Chem. 2015, 11, 773–783, doi:10.3762/bjoc.11.87

• limited. As a result, cells are self-renewed without loss of phenotype [32]. In a recent study, how nanoscale clustering of integrin ligands alters the mechano-regulation of integrins has been revealed with the assistance of molecular tension fluorescence microscopy [33]. In the step of nascent adhesion

Glycodendrimers: tools to explore multivalent galectin-1 interactions

• Jonathan M. Cousin and
• Mary J. Cloninger

Beilstein J. Org. Chem. 2015, 11, 739–747, doi:10.3762/bjoc.11.84

• mediated interactions. Dynamic light scattering and fluorescence microscopy were used to study the multivalent interaction of galectin-1 with the glycodendrimers in solution, and glycodendrimers were observed to organize galectin-1 into nanoparticles. In the presence of a large excess of galectin-1

• nanoparticles were characterized using dynamic light scattering (DLS) and fluorescence microscopy (FM) when varying ratios of galectin-1 were added to the glycodendrimers. The galectin-1/glycodendrimer nanoparticle aggregates were then used to inhibit the galectin-1 induced aggregation of DU145 human prostate

• -functionalized PAMAM dendrimers 1–4 were determined by fluorescence microscopy (FM) and dynamic light scattering (DLS). For fluorescence microscopy, galectin-1 was labeled with AlexaFluor-555, and aggregation was characterized when a large, medium, or slight excess of galectin-1 was used relative to the

Potential of acylated peptides to target the influenza A virus

• Daniel Lauster,
• Damian Pawolski,
• Julian Storm,
• Kai Ludwig,
• Rudolf Volkmer,
• Henry Memczak,
• Andreas Herrmann and
• Sumati Bhatia

Beilstein J. Org. Chem. 2015, 11, 589–595, doi:10.3762/bjoc.11.65

• for 24 h at 37 °C. Error bars indicate the standard deviation of three experiments. Fluorescence microscopy images of GUVs (left) and human erythrocytes (right) after incubation with C18-s2s-TAMRA. The overlap of DIC and rhodamine channels demonstrate the labeling of membranes by the fluorescent

A versatile δ-aminolevulinic acid (ΑLA)-cyclodextrin bimodal conjugate-prodrug for PDT applications with the help of intracellular chemistry

• Chrysie Aggelidou,
• Theodossis A. Theodossiou,
• Antonio Ricardo Gonçalves,
• Mariza Lampropoulou and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 2414–2420, doi:10.3762/bjoc.10.251

• for images d, e and f. Representative confocal fluorescence microscopy images of MCF7 cells after incubation with a solution of 2–fluorescein isothiocyanate-labeled 1-adamantylamine (1 mM/0.2 mM) PBS: (a, d) red fluorescence (λex = 568 nm, λem > 585 nm); (b, e) green fluorescence (λex = 488 nm, λem

Specific DNA duplex formation at an artificial lipid bilayer: fluorescence microscopy after Sybr Green I staining

• Emma Werz and
• Helmut Rosemeyer

Beilstein J. Org. Chem. 2014, 10, 2307–2321, doi:10.3762/bjoc.10.240

• (2b) – prepared by using compound 2a – was proven by fluorescence microscopy. Now, we simplify this technique by hybridizing an unlabelled DNA target strand to the bilayer-immobilized lipo-oligonucleotide and by using Sybr Green I (3, SG) [20][21][22] as a fluorescent double strand indicator [20][21

Expanding the scope of cyclopropene reporters for the detection of metabolically engineered glycoproteins by Diels–Alder reactions

• Anne-Katrin Späte,
• Verena F. Schart,
• Julia Häfner,
• Andrea Niederwieser,
• Thomas U. Mayer and
• Valentin Wittmann

Beilstein J. Org. Chem. 2014, 10, 2235–2242, doi:10.3762/bjoc.10.232

• proteins and mucin-type O-glycans [30]. Here, we show that 1 and 2 can be employed for both labeling of cell-surface glycoconjugates (detected by confocal fluorescence microscopy) and isolated glycoproteins (detected by Western blot). Results and Discussion For the synthesis of the cyclopropene-tagged

• Modified Eagle’s Medium (DMEM) supplemented with 5% FBS, 100 units mL–1 penicillin and 100 μg mL–1 streptomycin. All cells were incubated in a 5% carbon dioxide, water saturated incubator at 37 °C. Fluorescence microscopy with Tz–biotin 10. HEK 293T cells (22,000 cells/cm2) were seeded in 4-well ibiTreat μ

• Rebecca Faißt, Jessica Pfotzer, and Verena Goldbach for synthesis of cyclopropene derivatives and the Bioimaging Center of the University of Konstanz for providing the fluorescence microscopy instrumentation.

Multivalent scaffolds induce galectin-3 aggregation into nanoparticles

• Candace K. Goodman,
• Mark L. Wolfenden,
• Pratima Nangia-Makker,
• Anna K. Michel,
• Avraham Raz and
• Mary J. Cloninger

Beilstein J. Org. Chem. 2014, 10, 1570–1577, doi:10.3762/bjoc.10.162

• . Here, we show that lactose-functionalized dendrimers interact with galectin-3 in a multivalent fashion to form aggregates. The glycodendrimer–galectin aggregates were characterized by dynamic light scattering and fluorescence microscopy methodologies and were found to be discrete particles that

• /galectin-3 aggregates that were formed (as determined by DLS and fluorescence microscopy) was dependent on both the dendrimer concentration and the generation. Third and fourth generation glycodendrimers formed smaller, more monodisperse aggregates, than sixth generation glycodendrimers. Aggregates formed

• Supporting Information Fle 1, Figure S7 for 4 and 5. Fluorescence microscopy Fluorescence images were captured on either a Nikon Eclipse TE2000-U with a 60× oil immersion objective lens (2, 3, 4) or Olympus BX-61 with a 100× oil immersion objective (3, 4, 5). Exposure time was optimized for each sample and

Molecular recognition of surface-immobilized carbohydrates by a synthetic lectin

• Melanie Rauschenberg,
• Eva-Corrina Fritz,
• Christian Schulz,
• Tobias Kaufmann and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2014, 10, 1354–1364, doi:10.3762/bjoc.10.138

• β-D-galactose was observed by fluorescence microscopy. The selectivity and affinity of the synthetic lectin was screened in competition experiments. In addition, the carbohydrate binding of the synthetic lectin was compared with the carbohydrate binding of the lectins concanavalin A and peanut

• . Read out is performed with an array scanner using fluorescence microscopy or surface plasmon resonance. In recent years, microcontact printing (μCP) [21][22][23][24] has gained importance as a replication method for biological microarrays such as protein [25][26] and DNA microarrays [27][28][29][30

• measured with a Nano Wizzard 3 system (JPK Instruments AG, Berlin/Germany) in combination with processing software Gwyddion (http://www.gwyddion.net, version 2.25). All measurements were carried out on silicon substrates. Fluorescence microscopy: Fluorescence microscopy images were made by using an Olympus

Flow synthesis of a versatile fructosamine mimic and quenching studies of a fructose transport probe

• Matthew B. Plutschack,
• D. Tyler McQuade,
• Giulio Valenti and
• Peter H. Seeberger

Beilstein J. Org. Chem. 2013, 9, 2022–2027, doi:10.3762/bjoc.9.238

• is known to self-quench at high concentrations [21][22]. Trypan blue is routinely used to quench autofluorescence in confocal fluorescence microscopy and fluorescence activated cell sorting (FACS) [23][24], and dyes like Bromophenol Blue, Brilliant Blue R, and Methylene Blue have been applied to

• quenching properties as a function of concentration and in the presence of various quenchers. These data are critical for future uptake studies that use confocal fluorescence microscopy or FACS strategies. Normalized NBDM absorption and emission, 40 µM and 2 µM. NBDM fluorescence from 1–40 µM (PBS buffer

Synthesis and evaluation of cell-permeable biotinylated PU-H71 derivatives as tumor Hsp90 probes

• Tony Taldone,
• Anna Rodina,
• Erica M. DaGama Gomes,
• Matthew Riolo,
• Hardik J. Patel,
• Raul Alonso-Sabadell,
• Danuta Zatorska,
• Maulik R. Patel,
• Sarah Kishinevsky and
• Gabriela Chiosis

Beilstein J. Org. Chem. 2013, 9, 544–556, doi:10.3762/bjoc.9.60

• ; flow cytometry; fluorescence microscopy; PU-H71; tumor Hsp90; Introduction Heat shock protein 90 (Hsp90) is a molecular chaperone that functions to properly fold proteins to their active conformation through its ATPase activity [1]. These client proteins include many that are involved in malignant

• stained with DAPI (1 µg/mL). Cells were washed and then analyzed by flow cytometry (LSR-II, BD Biosciences). Fluorescence microscopy. K562 cells were treated with 10 μM 2g or DMSO (control) at 37 °C for 4 h. Cells were then collected, washed twice with PBS and attached to a chamber slide by centrifugation

Chemical modification allows phallotoxins and amatoxins to be used as tools in cell biology

• Jan Anderl,
• Hartmut Echner and
• Heinz Faulstich

Beilstein J. Org. Chem. 2012, 8, 2072–2084, doi:10.3762/bjoc.8.233

• , albeit under toxic conditions. Using rhodamine-labeled phalloidin, we could also study how membrane-permeable peptides are incorporated into the cell. Immediately after exposure the toxin was located on the plasma membrane of the cells as shown by fluorescence microscopy (Figure 6c), while after 6 h

• -phalloidin (3). (b) Growth inhibition of NIH 3T3 mouse fibroblasts by tetramethylrhodaminyl-phalloidin (3) versus phalloidin (1) after 72 h incubation time. (c) Binding and uptake of tetramethylrhodaminyl-phalloidin (3) in NIH 3T3 mouse fibroblasts after 1, 6 and 24 h, as documented by fluorescence

• microscopy. Chemical structure of amanitin with attachment site for conjugation to internalization-mediating moieties (R1, R3). NIH 3T3 mouse fibroblasts were incubated with various concentrations of α-amanitin and amanitin derivatives. Cell viability was determined after 72 h incubation time by MTT assay