A truncated haemoglobin (tHb) has been identified in an acidophilic and thermophilic methanotroph Methylacidiphilium infernorum. Hell's Gate Globin IV (HGbIV) and its related tHbs differ from all other bacterial tHbs due to their distinctively large sequence and polar distal haem pocket residues. Here we report the crystal structure of HGbIV determined at 1.96 Å resolution. The HGbIV structure has the distinctive 2/2 α-helical structure with extensions at both termini. It has a large distal site cavity in the haem pocket surrounded by four polar residues: His70(B9), His71(B10), Ser97(E11) and Trp137(G8). This cavity can bind bulky ligands such as a phosphate ion. Conformational shifts of His71(B10), Leu90(E4) and Leu93(E7) can also provide more space to accommodate larger ligands than the phosphate ion. The entrance/exit of such bulky ligands might be facilitated by positional flexibility in the CD1 loop, E helix and haem-propionate A. Therefore, the large cavity in HGbIV with polar His70(B9) and His71(B10), in contrast to the distal sites of other bacterial tHbs surrounded by non-polar residues, suggests its distinct physiological functions.
The synergetic effect of nitrogen-rich and CO2-philic filler and polymer in mixed matrix-based membranes (MMMs) can separate CO2 competently. The introduction of well-defined nanostructured porous fillers of pores close to the kinetic diameter of the gas molecule and polymer matrix compatibility is a challenge in improving the gas transportation characteristics of MMMs. This study deals with the preparation of porphyrin filler and the polysulfone (PSf) polymer MMMs. The fillers demonstrated uniform distribution, uniformity, and successful bond formation. MMMs demonstrated high thermal stability with a glass transition temperature in the range of 480-610 °C. The porphyrin filler exhibited microporous nature with the presence of π-π bonds and Lewis's basic functionalities between filler-polymer resulted in a highly CO2-philic structure. The pure and mixed gas permeabilities and selectivity were successfully improved and surpass the Robeson's upper bound curve's tradeoff. Additionally, the temperature influence on CO2 permeability revealed lower activation energies at higher temperatures leading to the gas transport facilitation. This can be granted consistency and long-term durability in polymer chains. These results highlight the unique properties of porphyrin fillers in CO2 separation mixed matrix membranes and offer new knowledge to increase comprehension of PSf performance under various contents or environments.
Biohydrogen as one of the most appealing energy vector for the future represents attractive avenue in alternative energy research. Recently, variety of biohydrogen production pathways has been suggested to improve the key features of the process. Nevertheless, researches are still needed to overcome remaining barriers to practical applications such as low yields and production rates. Considering practicality aspects, this review emphasized on anaerobic membrane bioreactors (AnMBRs) for biological hydrogen production. Recent advances and emerging issues associated with biohydrogen generation in AnMBR technology are critically discussed. Several techniques are highlighted that are aimed at overcoming these barriers. Moreover, environmental and economical potentials along with future research perspectives are addressed to drive biohydrogen technology towards practicality and economical-feasibility.
Biochar production from invasive species biomass discarded as waste was studied in a fixed bed reactor pyrolysis system under different temperature conditions for value-added applications. Prior to pyrolysis, the biomass feedstock was characterized by proximate, ultimate, and heating value analyses, while the biomass decomposition behavior was examined by thermogravimetric analysis. The heating values of the feedstock biomass ranged from 18.65 to 20.65 MJ/kg, whereas the volatile matter, fixed carbon, and ash content were 61.54-72.04 wt %, 19.27-26.61 wt % and 1.51-1.86 wt %, respectively. The elemental composition of carbon, hydrogen, and oxygen in the samples was reported to be in the range of 47.41-48.47 wt %, 5.50-5.88 wt % and 46.10-45.18 wt %, respectively, while the nitrogen and sulphur content in the biomass samples were at very low concentrations, making it more useful for valorization from environmental aspects. The biochar yields were reported in the range of 45.36-58.35 wt %, 28.63-44.38 wt % and 22.68-29.42 wt % at a pyrolysis temperature of 400 °C, 500 °C, and 600 °C, respectively. The biochars were characterized from ultimate analysis, heating value, energy densification ratio, energy yield, pH, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy and energy dispersive X-ray spectrometry (SEM and EDX), to evaluate their potential for value-added applications. The carbon content, heating value, energy densification ratio, and the porosity of the biochars improved with the increase in pyrolysis temperature, while the energy yield, hydrogen, oxygen, and nitrogen content of the biochars decreased. This study revealed the potential of the valorization of underutilized discarded biomass of invasive species via a pyrolysis process to produce biochar for value-added applications.
The HER2-positive patients occupy ~ 30% of the total breast cancer patients globally where no prevalent drugs are available to mitigate the frequent metastasis clinically except lapatinib and neratinib. This scarcity reinforced researchers' quest for new medications where natural substances are significantly considered. Valuing the aforementioned issues, this research aimed to study the ERBB2-mediated string networks that work behind the HER2-positive breast cancer formation regarding co-expression, gene regulation, GAMA-receptor-signaling pathway, cellular polarization, and signal inhibition. Following the overexpression, promotor methylation, and survivability profiles of ERBB2, the super docking position of HER2 was identified using the quantum tunneling algorithm. Supramolecular docking was conducted to study the target specificity of EPA and DHA fatty acids followed by a comprehensive molecular dynamic simulation (100 ns) to reveal the RMSD, RMSF, Rg, SASA, H-bonds, and MM/GBSA values. Finally, potential drug targets for EPA and DHA in breast cancer were constructed to determine the drug-protein interactions (DPI) at metabolic stages. Considering the values resulting from the combinational models of the oncoinformatic, pharmacodynamic, and metabolic parameters, long-chain omega-3 fatty acids like EPA and DHA can be considered as potential-targeted therapeutics for HER2-positive breast cancer treatment.