A novel type secoiridoid glucoside,hydrangenoside a from Hydrangea macrophylla

Hydrangenoside A, isolated along with its three congeners from Hydrangea macrophylla, was proved to have a novel type of structure which is thought to be biosynthesized through an aldol-type condensation of secologanin with a unit formed by the shikimate-malonate route followed by decarboxylation.     

Photon number squeezing of ultrabroadband laser pulses generated by microstructure fibers

To the best of our knowledge, we demonstrate for the first time the generation of photon number squeezing by spectral filtering for ultrabroadband light generated by microstructure fibers at 800 nm. A maximum squeezing of 4.6 dB is observed, corresponding to 10.3 dB after correcting for detection losses. We numerically analyzed the quantum dynamics of ultrashort laser pulse propagation through optical fibers by solving a nonlinear quantum Schr?dinger equation that included Raman scattering, especially for the quantum correlation of photon number fluctuation among frequency modes in broadband pulses.     

Compaction of single-chain DNA by histone-inspired nanoparticles

We elaborated a versatile experimental model of chromatin which consists of a single chain of long duplex DNA that interacts with well-defined cationic nanoparticles of various sizes. We found that the DNA compaction by nanoparticles is stepwise and progressive at the single-chain level. It is controlled by the ability of DNA to wrap nanoparticles, which is more efficient for larger particles and, similar to DNA-histone interaction, is optimal at a physiological salt concentration.     

Micellar cobaltporphyrin nanorods in alcohols

Cobalt(II) meso-tetrakis(4-hexadecylamidophenyl)porphyrin self-assembles in ethanol/1-propanol 2/1 (v/v) to form a rodlike micelle with nanoscale dimensions; the nanorod is a face-to-face aggregate having a hydrophobic corona around a polar core and is thus characterized as a reverse micelle.     

Control of bacteria adhesion by cell-wall engineering

UDP-MurNAc-pentapeptide derivative bacterial cell-wall precursors were synthesized as effective tools for surface display on living bacteria. Lactobacilli were incubated in the ketone-modified precursor-containing medium, and the ketone moiety was displayed on the bacterial surface through cell-wall biosynthesis. Oligomannose was coupled with the ketone moiety on the bacterial surface via a aminooxyl linker, thereby displaying this oligosaccharide on the surface of the bacteria. The increase in the adhesion of the sugar-displaying bacteria onto a concanavalin A-attached film compared to that of native bacteria was confirmed by microscopic observation and surface plasmon resonance measurement. The incorporation of the artificial cell-wall precursors was enhanced when incubated with fosfomycin, an inhibitor of cell-wall precursor biosynthesis.     

Synthesis of conjugated oligomers having aromatic and enediyne units alternately in the backbone that show intense fluorescence emission

[structure: see text] Synthesis and fluorescence properties of pi-conjugated compounds having alternately an aromatic ring such as benzene, pyridine, and thiophene and an enediyne unit in the backbone are described.     

Active site structure and redox processes of cytochrome c oxidase immobilised in a novel biomimetic lipid membrane on an electrode

Membrane-bound cytochrome c oxidase was attached to an electrode via a His-tag linker and studied by surface enhanced resonance Raman spectroscopy, demonstrating intact redox site structures and electron transfer between the electrode and the immobilized enzyme.     

Photoemission and ionization of He+ under simultaneous irradiation of fundamental laser and high-order harmonic pulses

We theoretically study the response of He+ exposed simultaneously to an intense Ti:sapphire laser and its 27th or 13th harmonic pulses. High-order harmonic emission from He+ is enhanced by many orders of magnitude compared with the case of the fundamental pulse alone. Moreover, while an individual 10 fs laser (wavelength lambda(F)=800 nm) or its 27th harmonic pulse with a peak intensity of 3 x 10(14) and 10(13) W/cm(2), respectively, ionizes no more than 5 x 10(-6) of He+, their combined pulse leads to a surprisingly high He2+ yield of 17%.