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Vanillin holds significant importance as a flavoring agent in various industries, including food, pharmaceuticals, and cosmetics. The CoA-dependent pathway for the biosynthesis of vanillin from ferulic acid involved feruloyl-CoA synthase (Fcs) and enoyl-CoA hydratase/lyase (Ech). In this research, the Fcs and Ech were derived from Streptomyces sp. strain V-1. The sequence conservation and structural features of Ech were analyzed by computational techniques including sequence alignment and molecular dynamics simulation. After detailed study for the major binding modes and key amino acid residues between Ech and substrates, a series of mutations (F74W, A130G, A130G/T132S, R147Q, Q255R, ΔT90, ΔTGPEIL, ΔN1-11, ΔC260-287) were obtained by rational design. Finally, the yield of vanillin produced by these mutants was verified by whole-cell catalysis. The results indicated that three mutants, F74W, Q147R, and ΔN1-11, showed higher yields than wild-type Ech. Molecular dynamics simulations and residue energy decomposition identified the basic residues K37, R38, K561, and R564 as the key residues affecting the free energy of binding between Ech and feruloyl-coenzyme A (FCA). The large changes in electrostatic interacting and polar solvating energies caused by the mutations may lead to decreased enzyme activity. This study provides important theoretical guidance as well as experimental data for the biosynthetic pathway of vanillin. [ABSTRACT FROM AUTHOR]

Antitumor-analgesic peptide（AGAP）is a novel recombinant polypeptide. The primary study showed that AGAP 1.0 mg/kg exhibited strong analgesic and antitumor effects. The tail vein administration of AGAP potently reduced pain behaviors in mice induced by intraplantar injection of formalin or intraperitoneal injection of acetic acid, without affecting basal pain perception. To further assess the mechanisms of AGAP, the effects of AGAP on sodium channels were assessed using the whole-cell patch clamp recordings in dorsal root ganglia (DRG) neurons. The results showed that AGAP (3-1000 nM) inhibited the sodium currents in small-diameter DRG neurons in a dose-dependent manner. 1000 nM AGAP could inhibit the current density-voltage relationship curve of sodium channels in a voltage-dependent manner and negatively shift the activation curves. 1000 nM AGAP could reduce the tetrodotoxin-resistant (TTX-R) sodium currents by 42.8% in small-diameter DRG neurons. Further analysis revealed that AGAP potently inhibited NaV1.8 currents by 59.4%, and negatively shifted the activation and inactivation kinetics. 1000 nM AGAP also reduced the NaV1.9 currents by 33.7%, but had no significant effect on activation and inactivation kinetics. Thus, our results demonstrated that submicromolar concentrations of AGAP inhibited TTX-R sodium channel in rat small-diameter DRG neurons. It is concluded that these new results may better explain, at least in part, the analgesic properties of this polypeptide.

In this paper, we firstly reported a C-type lectin cDNA clone of1029 bps from the larvae of A. Pernyi (Ap-CTL) using PCR andRACE techniques. The full-length cDNA contains an openreading frame encoding 308 amino acid residues which hastwo different carbohydrate-recognition domains (CRDs) arrangedin tandem. To investigate the biological activities in theinnate immunity, recombinant Ap-CTL was expressed in E. coliwith a 6-histidine at the amino-terminus (Ap-rCTL). Besidesacted as a broad-spectrum recognition protein binding to awide range of PAMPs and microorganisms, Ap-rCTL also hadthe ability to recognize and trigger the agglutination of bacteriaand fungi. In the proPO activation assay, Ap-rCTL specificallyrestored the PO activity of hemolymph blocked by anti-Ap-rCTL antibody in the presence of different PAMPs ormicroorganisms. In summary, Ap-rCTL plays an important rolein insect innate immunity as an pattern recognition protein.[BMB Reports 2013; 46(7): 358-363]

Pattern recognition receptors are known to participate in theactivation of Prophenoloxidase system. In this study, a1,3-β-D-glucan recognition protein was detected for the firsttime in Antheraea pernyi larvae (Ap-βGRP). Ap-βGRP waspurified to 99.9% homogeneity from the hemolymph usingtraditional chromatographic methods. Ap-βGRP specificallybind 1,3-β-D-glucan and yeast, but not E. coli or M. luteus.The 1,3-β-D-glucan dependent phenoloxidase (PO) activity ofthe hemolymph inhibited by anti-Ap-βGRP antibody could berecovered by addition of purified Ap-βGRP. These resultsdemonstrate that Ap-βGRP acts as a biosensor of 1,3-β-Dglucanto trigger the Prophenoloxidase system. A trace mountof 1,3-β-D-glucan or Ap-βGRP alone was unable to trigger theproPO system, but they both did. Ap-βGRP was specificallydegraded following the activation of proPO with 1,3-β-Dglucan.These results indicate the variation in the amount ofAp-βGRP after specific immune challenge in A. pernyihemolymph is an important regulation mechanism to immuneresponse. [BMB Reports 2013; 46(5): 264-269]

Utilization of the intestinal lymphatic pathway will allow extraordinary gains in lymph and tumors cascade-targeted delivery of oral drugs and awakening the innate/adaptive immunity of the body and the lesion microenvironment, in addition to improving oral bioavailability relative to other means of delivery of oral drugs. Here, inspired by the specific invasion route of intestinal microorganisms, we pioneered an immune-awakening Saccharomyces -inspired mesoporous silicon nanoparticle (yMSN) for the ingenious cascade-targeted delivery of therapeutic cancer vaccines and antitumor drugs to lymph and tumors via the intestinal lymphatic pathway. Encouragingly, yMSN high-loaded tumor-specific antigens (OVA, 11.9%) and anti-tumor drugs (Len, 28.6%) with high stability, namely Len/OVA/yMSN, efficiently co-delivered OVA and Len to their desired target sites. Moreover, yMSN concomitantly awakened the innate antitumor immunity of dendritic cells and macrophages, strengthening vaccine-induced adaptive immune responses and reversing macrophage-associated immunosuppression in the tumor microenvironment. Surprisingly, Len/OVA/yMSN treatment resulted in excellent synergistic antitumor efficacy and long-term antitumor memory in OVA-Hepa1-6-bearing mice. This high-performance nanocarrier provides a novel approach for lesion-targeting delivery of oral drugs accompanied with awakening of the innate/adaptive immunity of the lesion environment, and also represents a novel path for the oral delivery of diverse therapeutic agents targeting other lymph-mediated diseases. A Saccharomyces -inspired nanocarrier brings an ingenious cascade-target-delivery of therapeutic cancer vaccines and antitumor drugs respectively to lymph and tumors via intestinal lymphatic pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

Gangliosides are important components of the neuronal cell membrane and play a vital role in the development of neurons and the brain. They participate in neurotransmission and are considered as the structural basis of learning and memory. Gangliosides participate in several and important physiological processes, such as cell differentiation, cell signaling, neuroprotection, nerve regeneration and apoptosis. The stability of ion concentration in excitable cells is particularly important in the maintenance of a steady state of cells and in the regulation of physiological functions. Ion concentration has been found to be related to the ganglioside's regulation in many neurological diseases, and several studies have found that they can stabilize intracellular ion concentration by regulating ion channels, which highlights their important regulatory role in neuronal excitability and synaptic transmission. Gangliosides can influence some forms of ion transport, by directly binding to ion transporters or through indirect binding and activation of transport proteins via appropriate signaling pathways. Therefore, the important and special role of gangliosides in the homeostasis of ion concentration is becoming a hot topic in the field and a theoretical basis in promoting help gangliosides use as key drugs for the treatment of nervous system diseases. [ABSTRACT FROM AUTHOR]

Hemolin is a distinctive immunoglobulin superfamily member involved in invertebrate immune events. Although it is believed that hemolin regulates hemocyte phagocytosis and microbial agglutination in insects, little is known about its contribution to the humoral immune system. In the present study, we focused on hemolin in Antheraea pernyi (Ap -hemolin) by studying its pattern recognition property and humoral immune functions. Tissue distribution analysis demonstrated the mRNA level of Ap -hemolin was extremely immune-inducible in different tissues. The results of western blotting and biolayer interferometry showed recombinant Ap -hemolin bound to various microbes and pathogen-associated molecular patterns. In further immune functional studies, it was detected that knockdown of hemolin regulated the expression level of antimicrobial peptide genes and decreased prophenoloxidase activation in the A. pernyi hemolymph stimulated by microbial invaders. Together, these data suggest that hemolin is a multifunctional pattern recognition receptor that plays critical roles in the humoral immune responses of A. pernyi. [ABSTRACT FROM AUTHOR]

Pedicle screw placement is a common internal fixation technology used in spine surgery, with preoperative planning and assessment being one of the most important steps. Preoperative planning mainly refers to determining the path and parameters of screws, and preoperative assessment mainly refers to effects during and after operations (i.e., firmness, etc.). Technologies available at present lack effective quantitative assessments on the firmness of screws. Bone mineral density (BMD) is one of the most important influencing factors for firmness. To address the aforementioned problems, this study aimed to put forward quantitative assessments for the firmness of pedicle screws taking bone mass as the basis. In other words, quantitative assessments of the firmness of screw trajectories were made by computing the total mineral content of the bone supporting screws. Meanwhile, the quantitative assessment results of the firmness were used as the optimized objective functions to put forward and realize an automatic planning optimization method for screw trajectories. The findings of this study might provide more complete and simplified planning schemes for doctors, to enhance the postoperative firmness of screws effectively, prevent from issues such as the loosening of screws due to the low value of a patient's bone mass, and promote the effects of operations. [ABSTRACT FROM AUTHOR]

Anti-tumour-analgesic peptide (AGAP), one scorpion toxin purified from Buthus martensii Karsch, was known as its analgesic and anti-tumour activities. Trp38, a conserved aromatic residue of AGAP, might play important roles in its interaction with sodium channels. In this study, a mutant W38F was generated and effects of W38F were examined on hNav1.4, hNav1.5 and hNav1.7 by using whole-cell patch-clamp, which were closely associated to the biotoxicity of skeletal and cardiac muscles and pain signalling. The data showed that W38F decreased the inhibition effects of peak currents of hNav1.7, hNav1.4 and hNav1.5 compared with AGAP, notably, W38F reduced the analgesic activity compared with AGAP. The results suggested that Trp38 be a crucial amino acid involved in the interaction with these three sodium channels. The decreased analgesic activity of W38F might result from its much less inhibition of hNav1.7. These findings provided more information about the relationship between structure and function of AGAP and may facilitate the modification of other scorpion toxins with pharmacological effects. [ABSTRACT FROM AUTHOR]