Effect of BCD Plasma on a Bacteria Cell Membrane

Cell membrane rupture is considered to be one of the probable mechanisms for bacterial inactivation using barrier corona discharge （BCD） plasma. In this paper, the effect of the BCD plasma on the Escherichia coli （E. coli） bacteria cell wall was investigated through two analytical methods; Adenosine-5-triphosphate （ATP） assay and Atomic Force Microscopy （AFM）. The ATP assay results indicate an increase in the ATP content of samples which were exposed to the BCD plasma. This implies the bacteria cell rupture. Moreover, AFM images confirm a serious damage of the bacteria cell wall under the influence of the bactericidal agents of the plasma.

Editorial commentary on the special issue of Advances in Nanomedicine

Nanomedicine is a vast multidisciplinary field of life sciences.It assembles branches of the fundamental research disciplines biology,physics,and chemistry with medicine and their associated application technologies and instrumentation.Diagnostics and therapeutics are the two major application areas of nanomedicine.

New Physicochemical Treatment Method of Poppy Seeds for Agriculture and Food Industries

Poppy seeds （Papaver somniferum L.） are often attacked by various fungal dis- eases, and their field germination rate is low. The aim of this experiment was to increase the germination rate and growth of seedlings by modifying the poppy seeds using cold plasma dis- charge. The seeds were treated in a Plasonic AR-550-M under power of 500 W with argon gas flow of 50 mL/min, oxygen gas flow of 50 mL/min for different time durations in seconds （0, 180, 300, 600, 1800, 3000, 4200, and 5400）. The seed germination rate and growth of the seedlings were recorded. Cold plasma positively affected the seed germination rate for time exposure between 180～3000 s. Seedling acceleration on the sixth day of the experiment showed the highest values at exposure 180～600 s. Cold plasma seems to be a good physicochemical way to modify seeds without chemical agronomical application.

Description of a Putative Oligosaccharyl:S-Layer Protein Transferase from the Tyrosine <i>O</i>-Glycosylation System of <i>Paenibacillus alvei</i>CCM 2051^T

Surface (S)-layer proteins are model systems for studying protein glycosylation in bacteria and simultaneously hold promises for the design of novel, glyco-functionalized modules for nanobiotechnology due to their 2D self-assembly capability. Understanding the mechanism governing S-layer glycan biosynthesis in the Gram-positive bacterium Paenibacillus alvei CCM 2051T is necessary for the tailored glyco-functionalization of its S-layer. Here, the putative oligosaccharyl:S-layer protein transferase WsfB from the P. alvei S-layer glycosylation gene locus is characterized. The enzyme is proposed to catalyze the final step of the glycosylation pathway, transferring the elongated S-layer glycan onto distinct tyrosine O-glycosylation sites. Genetic knock-out of WsfB is shown to abolish glycosylation of the S-layer protein SpaA but not that of other glycoproteins present in P. alvei CCM 2051T, confining its role to the S-layer glycosylation pathway. A transmembrane topology model of the 781-amino acid WsfB protein is inferred from activity measurements of green fluorescent protein and phosphatase A fused to defined truncations of WsfB. This model shows an overall number of 13 membrane spanning helices with the Wzy_C domain characteristic of O-oligosaccharyl:protein transferases (O-OTases) located in a central extra-cytoplasmic loop, which both compares well to the topology of OTases from Gram-negative bacteria. Mutations in the Wzy C motif resulted in loss of WsfB function evidenced in reconstitution experiments in P. alvei ΔWsfB cells. Attempts to use WsfB for transferring heterologous oligosaccharides to its native S-layer target protein in Escherichia coli CWG702 and Salmonella enterica SL3749, which should provide lipid-linked oligosaccharide substrates mimicking to some extent those of the natural host, were not successful, possibly due to the stringent function of WsfB. Concluding, WsfB has all features of a bacterial O-OTase, making it the most probable candidate for the oligosaccharyl:S-layer protein transferase of P. alvei, and a promising candidate for the first O-OTase reported in Gram-positives.

Clinical applications of the CRISPR/Cas9 genome-editing system: Delivery options and challenges in precision medicine

CRISPR/Cas9 is an effective gene editing tool with broad applications for the pre-vention or treatment of numerous diseases.It depends on CRiSPR(clustered regularly inter-spaced short palindromic repeats)as a bacterial immune system and plays as a gene editing tool.Due to the higher specificity and efficiency of CRISPR/Cas9 compared to other editing ap-proaches,it has been broadly investigated to treat numerous hereditary and acquired ill-nesses,including cancers,hemolytic diseases,immunodeficiency disorders,cardiovascular diseases,visual maladies,neurodegenerative conditions,and a few X-linked disorders.CRISPR/Cas9 system has been used to treat cancers through a variety of approaches,with sta-ble gene editing techniques.Here,the applications and clinical trials of CRisPR/Cas9 in various illnesses are described.Due to its high precision and efficiency,CRISPR/Cas9 strategies may treat gene-related illnesses by deleting,inserting,modifying,or blocking the expression of specific genes.The most challenging barrier to the in vivo use of CRISPR/Cas9 like off-target effects will be discussed.The use of transfection vehicles for CRISPR/Cas9,including viral vectors(such as an Adeno-associated virus(AAV),and the development of non-viral vectors is also considered.

An Overview on SARS‑CoV‑2(COVID‑19)and Other Human Coronaviruses and Their Detection Capability via Amplification Assay,Chemical Sensing,Biosensing,Immunosensing,and Clinical Assays

A novel coronavirus of zoonotic origin(SARSCoV-2)has recently been recognized in patients with acute respiratory disease.COVID-19 causative agent is structurally and genetically similar to SARS and bat SARS-like coronaviruses.The drastic increase in the number of coronavirus and its genome sequence have given us an unprecedented opportunity to perform bioinformatics and genomics analysis on this class of viruses.Clinical tests like PCR and ELISA for rapid detection of this virus are urgently needed for early identification of infected patients.However,these techniques are expensive and not readily available for point-of-care(POC)applications.Currently,lack of any rapid,available,and reliable POC detection method gives rise to the progression of COVID-19 as a horrible global problem.To solve the negative features of clinical investigation,we provide a brief introduction of the general features of coronaviruses and describe various amplification assays,sensing,biosensing,immunosensing,and aptasensing for the determination of various groups of coronaviruses applied as a template for the detection of SARS-CoV-2.All sensing and biosensing techniques developed for the determination of various classes of coronaviruses are useful to recognize the newly immerged coronavirus,i.e.,SARS-CoV-2.Also,the introduction of sensing and biosensing methods sheds light on the way of designing a proper screening system to detect the virus at the early stage of infection to tranquilize the speed and vastity of spreading.Among other approaches investigated among molecular approaches and PCR or recognition of viral diseases,LAMP-based methods and LFAs are of great importance for their numerous benefits,which can be helpful to design a universal platform for detection of future emerging pathogenic viruses.

Hybrid lipopolymer vesicle drug delivery and release systems

Hybrid lipopolymer vesicles are membrane vesicles that can be self-assembled on both the micro-and nano-scale.On the nanoscale,they are potential novel smart materials for drug delivery systems that could combine the relative strengths of liposome and polymersome drug delivery systems without their respective weaknesses.However,little is known about their properties and how they could be tailored.Currently,most methods of investigation are limited to the microscale.Here we provide a brief review on hybrid vesicle systems with a specific focus on recent developments demonstrating that nanoscale hybrid vesicles have different properties from their macroscale counterparts.

Rapid determination of iron oxide content in magnetically modified particulate materials

Magnetically responsive composite materials have been used in interesting applications in various areas of bioscience, biotechnology, and environmental technology. In this work, a simple method to determine the amount of magnetic iron oxide nano- and microparticles attached to magnetically-modified partic- ulate diamagnetic materials has been developed using a commercially available magnetic permeability meter, The procedure is fast and enables dry particulate magnetically modified materials to be analysed without any modification or pretreatment. We show that the magnetic permeability can be measured for materials containing up to 20% magnetic iron oxide, The magnetic permeability measurements are highly reproducible.

Magnetic modification of diamagnetic agglomerate forming powder materials

A simple method for the magnetic modification of various types of powdered agglomerate forming dia- magnetic materials was developed. Magnetic iron oxide particles were prepared from ferrous sulfate by microwave assisted synthesis. A suspension of the magnetic particles in water soluble organic solvent （methanol, ethanol, propanol, isopropyl alcohol, or acetone） was mixed with the material to be modified and then completely dried at elevated temperature. The magnetically modified materials were found to be stable in water suspension at least for 2 months.

Biochars and their magnetic derivatives as enzyme-like catalysts mimicking peroxidases

Various materials have been extensively investigated to mimic the structures and functions of natural enzymes.We describe the discovery of a new catalytic property in the group of biochar-based carbonaceous materials,which are usually produced during biowaste thermal processing under specific conditions.The tested biochars exhibited peroxidase-like catalytic activ-ity.Biomaterial feedstock,pyrolysis temperature,size of resulting biochar particles or biochar modification(e.g.,magnetic particles deposition)influenced the peroxidase-like activity.Catalytic activity was measured with the chromogenic organic substrates N,N-diethyl-p-phenylenediamine(DPD)or 3,3′,5,5′-tetramethylbenzidine(TMB),in the presence of hydrogen peroxide.Magnetic biochar composite was studied as a complementary material,in which the presence of iron oxide particles enhances catalytic activity and enables smart magnetic separation of catalyst even from complex mixtures.The activity of the selected biochar had an optimum at pH 4 and temperature 32℃;biochar catalyst can be reused ten times without the loss of activity.Using DPD as a substrate,Km values for native wood chip biochar and its magnetic derivative were 220±5μmol L^(−1)and 690±80μmol L^(−1),respectively,while Vmax values were 10.1±0.3μmol L^(−1)min^(−1)and 16.1±0.4μmol L^(−1)min^(−1),respectively.Biochar catalytic activity enabled the decolorization of crystal violet both in the model solution and the fish pond water containing suspended solids and dissolved organic matter.The observed biochar enzyme mimetic activity can thus find interesting applications in environmental technology for the degradation of selected xenobiotics.In general,this property predestines the low-cost biochar to be a perspective supplement or even substitution of common peroxidases in practical applications.