Henan University of Technology

About: Henan University of Technology is a education organization based out in Zhengzhou, China. It is known for research contribution in the topics: Catalysis & Chemistry. The organization has 7648 authors who have published 6503 publications receiving 73067 citations. The organization is also known as: Hénán Gōngyè Dàxué.

Structure prediction and functional analyses of a thermostable lipase obtained from Shewanella putrefaciens.

Abstract: Previous experimental studies on thermostable lipase from Shewanella putrefaciens suggested the maximum activity at higher temperatures, but with little information on its conformational profile. In this study, the three-dimensional structure of lipase was predicted and a 60 ns molecular dynamics (MD) simulation was carried out at temperatures ranging from 300 to 400 K to better understand its thermostable nature at the molecular level. MD simulations were performed in order to predict the optimal activity of thermostable lipase. The results suggested strong conformational temperature dependence. The thermostable lipase maintained its bio-active conformation at 350 K during the 60 ns MD simulations.

Suppressing the Radiation-Induced Corrosion of Bismuth Nanoparticles for Enhanced Synergistic Cancer Radiophototherapy.

Abstract: The level of tumor killing by bismuth nanoparticles (BiNPs) as radiosensitizers depends strongly on the powerful particle-matter interaction. However, this same radiation leads to the structural damage in BiNPs, consequently weakening their specific physicochemical properties for radiosensitization. Herein, we studied the radiation-induced corrosion behavior of BiNPs and demonstrated that these damages were manifested by the change in their morphology and crystal structure as well as self-oxidation at their surface. Furthermore, artificial heterostructures were created with graphene nanosheets to greatly suppress the radiation-induced corrosion in BiNPs and enhance their radiocatalytic activity for radiotherapy enhancement. Such a nanocomposite allows the accumulation of overexpressed glutathione, a natural hole scavenger, at the reaction interfaces. This enables the rapid removal of radiogenerated holes from the surface of BiNPs and minimizes the self-radiooxidation, therefore resulting in an efficient suppression of radiation corrosion and a decrease of the depletion of reactive oxygen species (ROS). Meanwhile, the radioexcited conduction band electrons react with the high-level H2O2 within cancer cells to yield more ROS, and the secondary electrons are trapped by H2O molecules to produce hydrated electrons capable of reducing a highly oxidized species such as cytochrome c. These radiochemical reactions together with hyperthermia can regulate the tumor microenvironment and accelerate the onset of cellular redox disequilibrium, mitochondrial dysfunction, and DNA damage, finally triggering tumor apoptosis and death. The current work will shed light on radiosensitizers with an enhanced corrosion resistance for controllable and synergistic radio-phototherapeutics.

Mutagenesis induced by high hydrostatic pressure treatment: a useful method to improve the bacterial cellulose yield of a Gluconoacetobacter xylinus strain

Abstract: Bacterial cellulose (BC) is a new biomaterial which has wide application potential in various industries. BC industrialization requires bacterial strains with high BC productivity. The objective of this study is to increase the BC yield of a Gluconoacetobacter xylinus strain through mutagenesis induced by high hydrostatic pressure (HHP) treatment. In this study, the parental strain in its exponential phase was treated at 250 MPa and 25 °C for 15 min to induce mutagenesis using a HHP machine. The HHP-treated strains were incubated in glucose agar plate at 30 °C for 4 days. After the incubation, 50 larger colonies in these plates were randomly selected and cultivated to produce BC membrane in a tailor-made glass vessel, and wet weights of the BC membranes were tested. Compared with the parental strain, 29 mutants showed higher BC yields, of which eight mutants with BC yield >130.00 g/L were initially screened and were then cultivated for five generations to test their genetic stabilities for BC production. Among the eight mutants, M438, a mutant which showed the highest average BC yield (158.56 g/L) and lowest coefficient of variation (2.4%) for five generations, was finally screened as objective mutant. HHP treatment can serve as an effective method to cause mutagenesis in BC-producing bacteria. The HHP-treated strains with significantly higher BC yield than parental strain can be screened from the HHP-induced mutants.