Imaging membranes in live cells with nanometer-scale resolution promises to reveal ultrastructural dynamics of organelles that are essential for cellular functions. In this work, we identified photoswitchable membrane probes and obtained super-resolution fluorescence images membranes. We demonstrated the photoswitching capabilities eight commonly used probes, each specific plasma membrane, mitochondria, endoplasmic recticulum (ER) or lysosomes. These small-molecule readily label high probe...

The capability of 2D IR spectroscopy to elucidate time-evolving structures is enhanced by a programmable mid-IR pulse shaper that greatly improves the ease, speed, and accuracy data collection. Traditional ways collecting spectra are difficult implement, cause distorted peak shapes, result in poor time resolution and/or phase problems. We report on several methods for using computer-controlled germanium acoustooptic modulator overcomes above each method evaluated model metal carbonyl...

There is considerable interest in uncovering the pathway of amyloid formation because toxic properties likely stems from prefibril intermediates and not fully formed fibrils. Using a recently invented method collecting 2-dimensional infrared spectra site-specific isotope labeling, we have measured development secondary structures for 6 residues during aggregation process 37-residue polypeptide associated with type 2 diabetes, human islet (hIAPP). By monitoring kinetics at different labeled...

Spermatozoa must leave one organism, navigate long distances, and deliver their paternal DNA into a mature egg. For successful navigation delivery, sperm-specific calcium channel is activated in the mammalian flagellum. The genes encoding this (CatSpers) appear first ancient uniflagellates, suggesting that sperm use adaptive strategies developed ago for single-cell navigation. Here, using genetics, super-resolution fluorescence microscopy, phosphoproteomics, we investigate CatSper-dependent...

This letter reports a straightforward means of collecting two-dimensional electronic (2D-E) spectra using optical tools common to many research groups involved in ultrafast spectroscopy and quantum control. In our method femtosecond pulse shaper is used generate pair phase stable collinear laser pulses which are then incident on gas or liquid sample. The followed by an ultrashort probe that spectrally resolved. delay between the incremented amplitude shaping 2D-E spectrum generated following...

The pursuit of exceptionally high photoluminescence (PL) and stability is critical in the development novel fluorophores for use challenging bioimaging optoelectronic devices. Carbon nanodots (CDs) doped with heteroatoms provide a particularly attractive means effectively tailoring their intrinsic properties exploiting new phenomena. Here, we report one-step, scalable synthesis boron-and-nitrogen co-doped CD (BN-CD) outstanding optical unlike those nitrogen-doped (N-CD) solid state as well...

We report that the Gm7068 (CatSpere) and Tex40 (CatSperz) genes encode novel subunits of a 9-subunit CatSper ion channel complex. Targeted disruption CatSperz reduces current sperm rheotactic efficiency in mice, resulting severe male subfertility. Normally distributed linear quadrilateral nanodomains along flagellum, complex lacking CatSperζ is disrupted at ~0.8 μm intervals flagellum. This renders proximal flagellum inflexible alters 3D flagellar envelope, thus preventing from reorienting...

Trichoderma species are well-known biological control agents. In this study, metabolites from 128 isolates were extracted liquid cultures using ethyl acetate and tested for their activities against seven Phytophthora isolates. Following preliminary analysis, eight selected further tests. Among them, the atroviride/petersenii (KACC, Korea Agricultural Culture Collection, 40557) virens (KACC 40929) showed strongest inhibitory Treatment with KACC 40557 extract inhibited growth, induced...

Pulse shaping directly in the mid-IR is accomplished by using a germanium acousto-optic modulator (Ge AOM) capable of programmable phase and amplitude modulation for IR light between 2 18 μm. Shaped waveforms centered at 4.9 μm are demonstrated both frequency time domains. With 50% throughput efficiency, Ge AOM can generate much more intense pulses with higher resolution than indirect methods. Furthermore, stability shaped pulse proved sufficient cross correlation unshaped pulses. Thus,...

Amyloid forming proteins have been implicated in many human diseases. The kinetics of amyloid fiber formation are particular interest because evidence points to intermediate folding structures as potential cytotoxic species. standard methods for monitoring the use fluorescence or circular dichroism spectroscopy, which do not uniquely resolve secondary structures. In this work, we a new technology rapidly scanning 2D-IR spectra that allows us follow islet polypeptide (hIAPP) is involved type...

Membrane nanotubes or tunneling (TNTs) that connect cells have been recognized as a previously unidentified pathway for intercellular transport between distant cells. However, it is unknown how this delicate structure, which extends over tens of micrometers and remains robust hours, formed. Here, we found TNT develops from double filopodial bridge (DFB) created by the physical contact two filopodia through helical deformation DFB. The transition DFB to close-ended most likely triggered...

A germanium acousto-optic modulator was recently reported (Shim et al., Optics Letters, 31, 838, 2006) that is capable of generating phase and amplitude shaped femtosecond pulses directly in the mid-infrared. In this paper, design, implementation performance novel mid-IR shaper described detail as sub-50 fs optical parametric amplifier provides large bandwidth for generation complex pulse shapes. These details include acoustic power wavelength dependence deflection efficiency, stability...

We report selective population of the excited vibrational levels ${T}_{1u}$ CO-stretching mode in $\mathrm{W}(\mathrm{CO}{)}_{6}$ using phase-tailored, femtosecond mid-IR ($5.2\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$, $1923\text{ }{\mathrm{cm}}^{\ensuremath{-}1}$) pulses. An evolutionary algorithm was used to optimize specific populations. Stimulated emission peaks, indicative inversion, could be induced. Systematic truncation each optimized pulse allowed for increased understanding...

Islet amyloid polypeptide (IAPP, also known as amylin) is responsible for pancreatic deposits in type 2 diabetes. The deposits, well intermediates their assembly, are cytotoxic to β-cells and contribute the loss of β-cell mass associated with factors that trigger islet deposition vivo not understood, but peptide membrane interactions have been postulated play an important role formation. To better understand formation, two-dimensional infrared (2D IR) spectroscopy was used compare kinetics...

A three-beam femtosecond stimulated Raman scattering (SRS) scheme is formulated and demonstrated to simultaneously induce two different SRS processes associated with Raman-active modes in the same molecule. Two SR gains involving a common pump pulse are coupled compete: As one of Stokes beam intensities increases, other selectively suppressed. We provide theoretical description experimental evidence that selective suppression behavior due limited number photons used for both when an intense...

Abstract We introduce UnaG as a green-to-dark photoswitching fluorescent protein capable of high-quality super-resolution imaging with photon numbers equivalent to the brightest photoswitchable red protein. only fluoresces upon binding fluorogenic metabolite, bilirubin, enabling UV-free reversible easily controllable kinetics and low background under Epi illumination. The on- off-switching rates are controlled by concentration ligand excitation light intensity, respectively, where dissolved...

Specimen-induced aberration has been a major factor limiting the imaging depth of single-molecule localization microscopy (SMLM). Here, we report application label-free wavefront sensing adaptive optics to SMLM for deep-tissue super-resolution imaging. The proposed system measures complex tissue aberrations from intrinsic reflectance rather than fluorescence emission and physically corrects distortion more three-fold stronger previous limit. This enables us resolve sub-diffraction...

This paper presents the first scanning electron microscopy (SEM)-based DNA imaging in biological samples. novel approach incorporates a metal-free electro-stain reagent, formulated by combining DNA-binding proteins and synthetic polymers to enhance visibility of 2-nm-thick under SEM. Notably, molecules stain with appear as dark lines The resulting images exhibit thickness 15.0±4.0 nm. As SEM is primary platform, it integrates seamlessly various chemically functionalized large surfaces aid...

<title>Abstract</title> Vibrational spectroscopy is a powerful tool for spectral imaging of biological samples, thanks to its narrow bandwidth (10 cm⁻¹) compared fluorescence. Single-molecule vibrational has been demonstrated with near-field amplification as in surface-enhanced Raman or fluorescence detection stimulated excited and bond-selective fluorescence-detected infrared-excited spectro-microscopy. However, these methods involve complex sample preparation produce high backgrounds,...

Ovarian cancer usually metastasizes from the ovary to adjacent organs through direct invasion with blood vessels formed by endothelial cells. Targeting apoptosis of ovarian and angiogenesis is promising for anticancer therapy. Leaves Ipomoea sp. have reportedly shown promise in treating cancer. Here, we investigated apoptosis-inducing anti-angiogenic effects compounds isolated batatas vines (IBV). Phytochemical examination IBV led isolation verification eight (1-8): chlorogenic acid (1),...