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Changes in adenosine triphosphate (ATP) and peroxynitrite (ONOO–) concentrations have been correlated in a number of diseases including ischemia-reperfusion injury and drug-induced liver injury. Herein, we report the development of a fluorescent probe ATP-LW, which enables the simultaneous detection of ONOO– and ATP. ONOO– selectively oxidizes the boronate pinacol ester of ATP-LW to afford the fluorescent 4-hydroxy-1,8-naphthalimide product NA-OH (λex = 450 nm, λem = 562 nm or λex = 488 nm, λem = 568 nm). In contrast, the binding of ATP to ATP-LW induces the spirolactam ring opening of rhodamine to afford a highly emissive product (λex = 520 nm, λem = 587 nm). Due to the differences in emission between the ONOO– and ATP products, ATP-LW allows ONOO– levels to be monitored in the green channel (λex = 488 nm, λem = 500–575 nm) and ATP concentrations in the red channel (λex = 514 nm, λem = 575–650 nm). The use of ATP-LW as a combined ONOO– and ATP probe was demonstrated using hepatocytes (HL-7702 cells) in cellular imaging experiments. Treatment of HL-7702 cells with oligomycin A (an inhibitor of ATP synthase) resulted in a reduction of signal intensity in the red channel and an increase in that of the green channel as expected for a reduction in ATP concentrations. Similar fluorescence changes were seen in the presence of SIN-1 (an exogenous ONOO– donor).

Liver fibrosis has accounted for liver diseases and overall mortality, but no relevant drug has been developed. Filamentous fungi are important resources of natural products for pharmaceutical development. Calcarisporium arbuscula is a mushroom endophytic fungus, which primarily produces aurovertins. Here, in an aurovertin null-production mutant, one silent gene cluster (mca17) was activated by overexpression of a pathway-specific zinc finger transcriptional regulator, and a tetramic acid-type compound (1, MCA17-1) was identified. Along with detailed structural characterization, its biosynthesis was proposed to be produced from the core PKS-NRPS hybrid enzyme. Moreover, 1 suppressed the activation of LX-2 upon transforming growth factor-β (TGF-β) challenge and had stronger bioactivity than the positive control obeticholic acid (OCA) against liver fibrosis. Our work suggested that this engineered fungus could be a producer of 1 for promising pharmaceutical development, and alternatively, it would be developed as a mushroom ingredient in dietary therapy to prevent liver fibrosis.

Fluorescence probes are emerging as appealing tools for tumor imaging, although the discovery of ideal probes with high tumor selectivity and desirable tumor-to-normal contrast remains challenging. There are currently two strategies used for designing tumor-targeted probes. One is employing tumor-targeting agents and the other is tumor-microenvironment-activatable probes. Although these two strategies have been widely explored, there are few reports on the comparison of probe performance designed based on the two strategies. Herein, by targeting somatostatin receptors (SSTR) overexpressed in neuroendocrine tumors with octreotide (OCT), we have designed two probes, with probe

Elucidating the structural characteristics and changes of lignin during biorefining is considerably important for lignin valorization. To examine the structural transformations of lignin under deep...

The natural lignin macromolecule is structurally complex and heterogeneous polymers. Herein, to comprehend the dynamic structural characteristics of poplar (Populus tomentosa) lignin during the gro...

Making full use of the lignocellulose is of great significance to the current biorefinery enterprises. As a natural macromolecule polymer, lignin has a prominent potential as renewable feedstock to...

Lignin nanoparticles offer a way for a high value use of the renewable resources. However, there are few green and facile methods so far for producing lignin nanoparticles with both high yield and ...

To understand the structural features and transformations of hybrid Pennisetum (HP) lignin, an integrated treatment on the basis of microwave-assisted hydrothermal pretreatment (MHTP) (at 180–200 °...

Understanding of the fundamental chemistry of lignin macromolecules in lignocellulosic biomass will facilitate the further development of renewable biofuel and biomaterial production. In the present study, to thoroughly delineate the detailed structural characteristics of the native lignin in the three major Eucalyptus woods, MWL, CEL, and EHL preparations were sequentially isolated from the diverse Eucalyptus wood. Parallelly, a modified enzyme lignin (DEL) based on double ball-milling and enzymatic hydrolysis was also prepared with superhigh yield (102.5–109.5%) from same Eucalyptus wood. The structural characteristics of all the lignin preparations were elaborately investigated by HPAEC, GPC, and NMR techniques (2D-HSQC and 31P NMR). Results showed that the contents of different substructures (β-O-4, β-β, β-5, and β-1) and S/G ratios of lignin macromolecules varied among these Eucalyptus species. As compared to the β-O-4 content in the extracted lignins (MWLs and CELs, 44.5–60.2/100Ar), the residual li...

The thermodynamic parameters characterizing the conformational stability of the human acidic fibroblast growth factor (hFGF-1) have been determined by isothermal urea denaturation and thermal denaturation at fixed concentrations of urea using fluorescence and far-UV CD circular dichroism (CD) spectroscopy. The equilibrium unfolding transitions at pH 7.0 are adequately described by a two-state (native ↔ unfolded state) mechanism. The stability of the protein is pH-dependent, and the protein unfolds completely below pH 3.0 (at 25 °C). hFGF-1 is shown to undergo a two-state transition only in a narrow pH range (pH 7.0−8.0). Under acidic (pH 8.0) conditions, hFGF-1 is found to unfold noncooperatively, involving the accumulation of intermediates. The average temperature of maximum stability is determined to be 295.2 K. The heat capacity change (ΔCp) for the unfolding of hFGF-1 is estimated to be 2.1 ± 0.5 kcal·mol-1·K-1. Temperature denaturation experiments in the absence and presence of u...