Streptococcal Pharyngitis detection using H-1 antigen (glycan probe) conjugated Gold Nanoparticles

A group from Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran, etc. has reported about a Nanobiosensor based on H-1 antigen-Gold NanoParticles (AuNPs) aggregation detecting M1 Streptococcal Pharyngitis.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9354983/

Streptococcus pyogenes (GAS) is a Gram positive bacterium that causes a wide variety of clinical conditions, ranging from acute pharyngitis to severe invasive diseases. A common method for the diagnosis of streptococcal pharyngitis is a physical examination by a physician and then a bacterial culture of throat swab. Until now, various types of biosensors were developed to diagnose GAS for clinical use. Those are based on antibody-antigen interactions, or on an isothermal nucleic acid amplification technology. Nevertheless, they are not widely used by clinicians worldwide, which may be related to the high cost.

The nanobiosensors based on the aggregation of AuNPs are well-known, and have been studied as an easy-to-use diagnosis of pathogens, where the presence of a specific antigen in a colloidal medium containing bioreceptor–AuNPs conjugates results in the aggregation of nanoparticles. Since it is known that M1 GAS binds to H-1 antigen, in this study, a sugar code present on oral epithelial cells, Lacto-N-fucopentaose I-biotin (H-1-biotin) was conjugated on avidin-AuNPs as an antigen to detect M1 GAS.

Based on the value of red-shift in SPR position, a calibration curve for detection of M1 GAS was plotted at a concentration range from 1 × 102 up to 1 × 107 CFU/ml. It was found that M1 GAS was detected in a wide concentration range (1 × 103 – 1×106 CFU/ml) with a linear response and a short detection time of 20 min.

Lectins specific to bisecting GlcNAc

A group from Department of Chemistry, Georgia State University, Atlanta GA USA, etc. has reported about lectins specific to bisecting GlcNAc.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9241959/

Many plant lectins could tolerate the bisecting GlcNAc, among which the bindings of PHA-E and Calsepa were enhanced. It was observed that even at a low concentration (1 μg mL−1), PHA-E and Calsepa showed bindings to non-bisected N-glycans, which would pose a significant problem in their wide applications of bisected glycan identification and cancer biomarker discovery. Surprisingly, PHA-L exhibited specific recognition of bisected biantennary N-glycans, which could find promising implementation in probing such structures, e.g., in antibodies, where β1-6-branched glycans are absent.
However, it should be noted that PHA-L has a strong specificity for tri/tetra antennary N-glycans.

O-Glycosylation changes in serum IgG3 could be a marker for inflammation development in advanced endometriosis

A group from Division of Laboratory Diagnostics, Faculty of Pharmacy, Wroclaw Medical University, Poland, etc. has reported that O-Glycosylation changes in serum IgG3 could be a marker for inflammation development in advanced endometriosis.
https://www.mdpi.com/1422-0067/23/15/8087/htm

Structurally, human IgG N-linked glycans are typically biantennary complexes. The second N-glycosylation site is found in the VH and VL (heavy and light chain of variable regions, respectively) and has been observed in 15–25% of all serum IgG. The presence of glycans in the IgG Fab region may contribute to higher antibody stability and modulate antigen binding. For IgG3, apart from N-glycans present in the Fab and Fc regions, the presence of O-linked glycans in the hinge region is also observed.

In blood serum, about 10% of IgG3 polyclonal antibodies and about 13% of IgG3 monoclonal antibodies are considered to contain O-glycans. Each IgG3 molecule can contain up to three O-glycans linked to threonine residues in the triple repeat regions within the hinge region. Although the function of IgG O-glycosylation is still not fully understood, the structure of the hinge region is hypothesized to be able to protect the immunoglobulin from proteolytic cleavage, and may also help maintain the extended conformation and flexibility of IgG3.

In this study, it was examined whether O-glycans are expressed in serum IgG in advanced endometriosis, and also whether, additionally to the presence of biantennary N-glycans, there are also highly branched N-glycans in IgG, and if so, whether the degree of their expression is characteristic of advanced endometriosis.

For the analysis of serum IgG O-glycosylation and the expression of multi-antennary N-glycans, lectin-ELISA with lectins specific to O-glycans (MPL, VVL, and Jacalin) and highly branched N-glycans (PHA-L) was used. And also, isolated serum IgG, i-IgG, and native serum IgG, s-IgG, were examined as samples.

The results were striking. In the case of s-IgG, the clinical value was limited. In the case of i-IgG, however, a maximum high clinical value (AUC = 1) was obtained with all four lectins used, both when comparing women with advanced endometriosis to healthy women and healthy women to a non-endometriosis group.
While this research has shown that both the expression of O-glycans and highly branched N-glycans in IgG may have a potential application in the diagnostics of advanced endometriosis, at the present stage of research, these conclusions mainly concern IgG isolated from serum. This makes it difficult to apply this type of determination in routine diagnostics due to the laborious and time-consuming procedure of protein isolation and purification. Nevertheless, this direction of research seems to be promising, and the development of a simple and fast protein isolation procedure is required.

Fumigation treatment was better than bioagent treatment in continuous cropping fields: Why is that happened?

A group from School of Minerals Processing and Bioengineering, Central South University, Changsha, China, etc. has reported that fumigation treatment was better than bioagent treatment in continuous cropping fields.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9354655/

Continuous cropping alters soil physiochemical properties and microbial community, causes soil salinization and acidification, accumulates harmful microbes, reduces fertilizer efficiency, and leads to severe soil-borne diseases, resulting in yield reduction and huge economic losses in agriculture production.

In this study, fumigation and biological agent treatments were evaluated to alleviate continuous cropping barriers. Three fumigation treatments, namely, chloropicrin (FM1), dazomet (FM2), and untreated control (CK_FM), and three biological treatments, namely, two biological agents (AG1 and AG2) offered by Prof. Jian Ye from the Institute of Microbiology, CAS, and untreated control (CK_AG) were compared.

Compared with the biological agent treatment, fumigation treatment had stronger disease inhibition effects. Furthermore, not only did the fumigation treatment increase pH, but it also increased nutrient availability in soil and stimulated crop growth.

The bacterial diversity was significantly reduced by the application of fumigants, compared with the biological agents, which caused a significant increase in bacterial diversity. This could be explained by the fact that fumigation chemicals are often toxicants to organisms. Fumigants are well-known poisonous substances used in killing insects, nematodes, and other animals or plants that cause damage to foods, seeds, or human dwelling. Although it is widely accepted that the diverse soil microbial community would benefit above-ground crops against disease infection and promote plant growth, this was in contrast to the results obtained in this study for fumigation treatment.

This can be explained as follows: fumigation treatment disrupted the entire soil microbial ecosystem and also leaded to changes in soil characteristics and plant performance, and thereby the crop benefitted from the reassembled rhizosphere microbiome resulting in the effective alleviation of continuous cropping barriers.

Stratifin (SFN) and Presepsin (P-SEP) could be used as prognostic biomarkers for severe COVID-19 progression

A group from Division of Medical Safety Science, National Institute of Health Sciences, Japan, etc. has reported that stratifin (SFN) and presepsin (P-SEP) could be used as prognostic biomarkers for severe COVID-19 progression.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9188980/

COVID-19 is a respiratory disease with a wide range of manifestations, from asymptomatic to severe cases with ARDS.18 Although about 80% of patients with COVID-19 experience only mild or moderate symptoms and have a favorable prognosis, the remaining patients worsen to severe or critical stage, and their prognosis, largely driven by severe ARDS, is poor. Therefore, early detection of the severe COVID-19 cases is important.

In the present study, five biomarkers for lung injury, SP-D, KL-6, P-SEP, KAL and SFN were analyzed, all of which have been suggested to be related with ARDS or its typical histological pattern diffuse alveolar damage (DAD), in serum samples collected serially from patients with COVID-19. It was found for the first time that serum SFN was significantly elevated in patients with severe COVID-19 compared to patients with mild or moderate symptoms. SFN, as well as P-SEP which has been suggested as a biomarker for severe COVID-19.

Both serum SFN and P-SEP were obviously elevated at the pre-severe stage. The AUC values [95% CI] of these proteins in diagnosing the pre-severe stage were 0.83 [0.76–0.90] for SFN and 0.79 [0.69–0.89] for P-SEP. When the cutoff values of SFN and P-SEP for discriminating the pre-severe condition from the mild/moderate condition on COVID-19 patients were set at 0.81 ng/mL and 374 pg/mL, the diagnostic sensitivity and specificity were 81.5% and 70.1% for SFN, and 76.9% and 71.9% for P-SEP, respectively.

Plant growth promoting ability of rhizobacteria strains isolated from Polyporus umbellatus

A group from School of Pharmaceutical Sciences, Peking University, Beijing, China, etc. has reported about mycorrhizal bacteria strains isolated from Polyporus umbellatus.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9340266/

Fungal pathogens cause a range of serious plant diseases, such as Fusarium wilt, and are responsible for most of the diseases in agricultural ecosystems.
There are two main ways to deal with the effects of these diseases:
One is to develop disease-resistant plants, and
the other is to use chemical fungicide to control the spread of pathogens.
However, these two methods have the disadvantages of long cycle and drug resistance of pathogens. A practical and sustainable strategy for dealing with phytopathogenic fungal diseases is therefore the application of biological control agents (BCAs).

Several bacteria have been isolated from plants and fungi, most of which belong to the genera Bacillus and Pseudomonas, and it has been demonstrated that those genera exhibit satisfactory biological activity and marked biocontrol potential.

In this paper, 21 rhizobacteria strains were isolated from mycorrhizal samples of Polyporus umbellatus, and evaluated from viewpoints of agricultural sustainability without requiring the overuse of hazardous fungicide and plant growth promoting ability such as producing IAA, siderophore, etc. and dissolving phosphate.

Among those isolated strains, it was found that the Pseudomonas strain ZL8 shows the highest performance as plant growth-promoting bacteria (PGPB). Nineteen compounds were identified from the fermentation broth of the strain ZL8, of which 2,4-diacetylphloroglucinol (DAPG) showed a significant inhibitory effect on phytopathogenic fungi with a minimum inhibitory concentration of 3.12–25 μg/mL. The plant growth promoting ability was evaluated with using Salvia miltiorrhiza, and the effect was so significant as shown below.

where, Fo. means Fusarium oxysporum

Green tea catechin, epigallocatechin gallate (EGCG), could be a pan-coronavirus attachment inhibitor

A group from Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON, Canada has reported that green tea catechin, epigallocatechin gallate (EGCG), could be a pan-coronavirus attachment inhibitor.
https://www.nature.com/articles/s41598-022-17088-0

Here, it was evaluated and characterized the inhibitory activity of EGCG against entry of human seasonal and highly pathogenic coronavirus (CoVs). Then, it was demonstrated that EGCG inhibits entry of a broad range of CoVs into physiologically relevant human lung epithelial cells. And, furthermore, EGCG inhibited binding of multiple human CoVs to cell surfaces, suggesting that this natural product inhibits a highly conserved step in CoV attachment, such as primary attachment to cell-surface heparan sulfate.
Focusing on SARS-CoV-2, it was shown that EGCG competitively inhibits virion attachment to heparin, a structural analog of Heparan Sulfate. These findings further support understanding of the antiviral mechanisms of EGCG against CoVs, and identify a highly conserved antiviral target for the development of improved antiviral molecules to prevent infection with diverse CoVs, including potential future emerging CoVs.

A lectin-Fc fusion protein (i.e., lectibody) recognizing cancer specific high mannose glycans would be a useful drug in cancer therapy

A group from Department of Pharmacology and Toxicology, University of Louisville School of Medicine, KY, USA, etc. has reported that a lectin-Fc fusion protein (i.e., lectibody) recognizing cancer specific high mannose glycans would be a useful drug in cancer therapy.
https://onlinelibrary.wiley.com/doi/10.1111/pbi.13902

Avaren-Fc (AvFc) is a lectin-Fc fusion protein (i.e., lectibody) produced in Nicotiana benthamiana, which selectively recognizes cancer-associated high-mannose glycans. A glycovariant of AvFc (AvFcΔXF) was developed by eliminating plant glycans, including the coreα1,3-fucoseand β1,2-xylose residues. The successful removal of these glycans was confirmed by glycan analysis using HPLC.

This study has demonstrated that AvFcΔXF induces more a potent ADCC response in vitro and delays the growth of murine B16F10 melanoma in both a flank tumor model as well as a model of metastasisin vivo, suggesting that high mannose glycans may be a useful druggable biomarker in cancer therapy.

where, AvFcΔlec means a variant lacking sugar-binding activity

An extract from coffee leaf (Coffea Arabica) effectively inhibited SARS-CoV-2 infection

A group from Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan, etc. has reported that an extract from coffee leaf (Coffea Arabica) effectively inhibited five Variants of SARS-CoV-2 (Alpha, Beta, Gamma, Delta, and Omicron strain) from entering host cells.
https://www.ijbs.com/v18p4677.htm

At 100 μg/ml, coffee leaf extract had a significant inhibitory effect on the infection of five VOC (Alpha, Beta, Gamma, Delta, and Omicron strain) pseudoviral SARS-CoV-2 as shown below.

In the coffee extract, four main compounds, including caffeine, CGA, quinic acid, and mangiferin, were identified. ACE2 TR-FRET Assay was used to evaluate inhibitory effect of Spike-ACE2 interactions. Due to the nature of the compounds, mangiferin and CGA were soluble in DMSO, and caffeine and quinic acid were soluble in water. It was demonstrated that treatment with four main compounds could inhibit the activity of Spike-ACE2.

Rice Rhizosphere: Arthrobacter sp. GN70 could be the best PGPR

A group from Department of Life Science, Dongguk University-Seoul, Goyang 10326, Korea has reported that Arthrobacter sp. GN70 inoculated into the rice plants showed a significantly positive effect on shoot length, root length, fresh plant weight, and dry plant weight.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9228311/

In this study, 504 strains were isolated through culture-dependent methods and tested for the PGPB traits for each strain. Based on its high IAA value, PGPB traits, and antagonism towards pathogenic microorganisms, Arthrobacter sp. GN70 was selected for inoculation in rice plants, under lab and greenhouse conditions. Strain GN70 successfully attached to the roots, produced fibril matrix, and enhanced the rice plant growth, lateral roots, and weight. The strain also showed antagonistic effects towards plant and human pathogens.

The Arthrobacter species, designated as GN70, produced the highest amount of IAA (50.3 µg/mL) among other PGPB including Sphingomonas, Ideonella, Burkholderia, and Agromyces.
The colonization of the rice root surface by Arthrobacter sp. GN70 was significant as shown below.

(a) Arthrobactor sp. colonized, (b) control

Arthrobacter sp. GN70 produces EPS, which may hold water or increase the water-holding capacity in the soil to assist the bacteria and the plant roots under water-deficit stress. The ability to form biofilms both enhances bacterial survival and also enhances plant growth through the various PGPR-associated mechanisms. The GN70 can be utilized as plant growth promoters, suppressors of plant pathogens, and alleviators of water-deficit stress. Actually, the antifungal activity of GN70 showed an inhibitory region in the F. proliferatum KACC 44025, which mainly affects the rice plant with rice spikelet rot disease.

Based on the t-test, the rice seeds inoculated with Arthrobacter sp. GN70 increased significantly in shoot length, root length, fresh plant weight, and dry plant weight by 143.5%, 83.5%, 112.1%, and 256.7%, respectively.

Powered by WordPress |Copyright © 2020 Emukk. All rights reserved