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The synthesis of konjac glucomannan-graft-polyacrylamide (KGM-g-PAM) was carried out at 25°C by γ-irradiation under a N2 atmosphere. The effects of absorbed radiation dosage and monomer concentration on grafting yield and water absorbency were studied. The grafted copolymers were characterized using Fourier Transform Infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), x-ray diffraction (XRD), thermogravimetric analysis (TGA) and gel permeation chromatography (GPC). The grafting yield was observed to increase with increasing absorbed dosage and monomer concentration. Compared with the original KGM, the grafted copolymers exhibited better thermal stability and water absorbency. The results suggest that γ-irradiation is convenient and efficient for inducing graft copolymerization of KGM and acrylamide (AM).

Late diagnosis and lack of specific therapeutic targets contribute to the low survival rate of patients with epithelial ovarian cancer (EOC), the most lethal gynecologic malignancy. Therefore, the screening of diagnostic markers and the identification of therapeutic targets are urgently required. Heat shock factor 1 (HSF1) has been demonstrated to be overexpressed in certain malignancies and to be involved in tumor initiation, development, transformation and metastasis. It is believed that HSF1 is a promising candidate for antitumor therapy. However, its expression pattern and function in ovarian cancer are far from being fully elucidated. Therefore, we examined the HSF1 expression in human EOC tissues, and evaluated its carcinogenesis-promoting activity in a xenograft tumor model. Examination of HSF1 expression in human EOC tissues was performed by immunohistochemical assay using ovarian tissue blots. Specific short hairpin RNA (shRNA) against HSF1 was employed to knockdown HSF1 in SKOV3 cells. Cell proliferative activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay; cell cycle distribution and apoptosis were determined by flow cytometric analysis. In normal ovarian tissues, HSF1 was barely detected, whereas, high expression of HSF1 was found in malignant EOC tissues, including serous, mucinous, endometrioid, and clear cell EOC tissues. Suppressed proliferative activity and intensified apoptosis were observed in HSF1-knockdown SKOV3 cells. In nude mouse xenografts, downregulation of HSF1 was found to cause reduced carinogenesis, indicating the antitumor effect induced by modulation of HSF1 against EOC. Our findings suggest that HSF1 may be considered as a potential candidate diagnostic marker of human EOC, and that modulation of HSF1 could be a promising therapeutic strategy against human EOC.

orthogonal suppressor tRNA holds the key to the incorporation efficiency. Recently, improved incorporation is achieved in E. coli strain C321.ΔA, in which all amber codons, accounting for 8% of stop codons in E. coli, [1] are replaced and prfA is removed away from the genome. [2] However, it will be extremely lethal for a cell to simultaneously interfere with all three stop codons. Saturation mutagenesis for molecular evolution is another application restricted by termination mechanisms. Stop codon involved in NNN randomized codon causes undesired premature termination. One stop codon is still generated even with NNK or NNS, moreover, the reduced codon set excludes codons with high usage frequency (Figure S1, Supporting Information). We anticipate that complete codon-dependent termination defect protein translation could efficiently liberate all codons for sense function and improve all the genetic code engineering applications (Figure 1).In the cell, termination of translation includes both the essential mechanism of class-I release factors and alternative mechanisms, [3] such as tmRNA (ssrA) mediated transtranslation [4] and translation stalling rescue. [5] As alternative termination ArfT in F. tularensis, [6] ResQ in Bacillus subtilis [7] are reported. In contrast to RF1, there is still no feasible approach for deletion of RF2, major class-I release factor in charge of the essential termination and plays a critical role in alternative terminations as well, i.e., post-peptidyl transfer quality control and alternative ribosome rescue. [8] However, cell viability becomes a barrier for in vivo assessment of global termination function. Therefore, there is strong curiosity about what if losing all essential termination machineries.Essential genes cannot be genetically deleted in a living cell. Pdt peptide containing 27 amino acids in length evolved from Mesoplasma florum Lon protease (mf-Lon) is demonstrated as being able to specifically target protein to efficient degradation in E. coli. [9] Pdt-tag is fused to nascent chain release factor RF1 and RRF respectively in E. coli MG1655pro, but failed on prfB encoding release factor RF2. Thus far, complete removal of all termination functions in either living cell or cell lysate was not yet achieved.Here, we present one efficient in vitro protein synthesis with 64 sense codons (iPSSC). The mf-Lon directed protein degradation is demonstrated as one efficient approach for the Termination of translation is essential but hinders applications of genetic code engineering, e.g., unnatural amino acids incorporation and codon randomization mediated saturation mutagenesis. Here, for the first time, it is demonstrated that E. coli Pth and ArfB together play an efficient translation termination without codon preference in the absence of class-I release factors. By degradation of the targeted protein, both essential and alternative termination types of machinery are completely removed to disable codon-dependent termination in cell extract. Moreover, a total of 153 engineered tRNAs...