Conventional Enrichment Research Articles

Challenging trophic position assessments in complex ecosystems: Calculation method, choice of baseline, trophic enrichment factors, season and feeding guild do matter: A case study from Marquesas Islands coral reefs.

Assessments of ecosystem functioning are a fundamental ecological challenge and an essential foundation for ecosystem-based management. Species trophic position (TP) is essential to characterize food web architecture. However, despite the intuitive nature of the concept, empirically estimating TP is a challenging task due to the complexity of trophic interaction networks. Various methods are proposed to assess TPs, including using different sources of organic matter at the base of the food web (the 'baseline'). However, it is often not clear which methodological approach and which baseline choices are the most reliable. Using an ecosystem-wide assessment of a tropical reef (Marquesas Islands, with available data for 70 coral reef invertebrate and fish species), we tested whether different commonly used TP estimation methods yield similar results and, if not, whether it is possible to identify the most reliable method. We found significant differences in TP estimates of up to 1.7 TPs for the same species, depending on the method and the baseline used. When using bulk stable isotope data, the choice of the baseline significantly impacted TP values. Indeed, while nitrogen stable isotope (δ15N) values of macroalgae led to consistent TP estimates, those using phytoplankton generated unrealistically low TP estimates. The use of a conventional enrichment factor (i.e. 3.4‰) or a 'variable' enrichment factor (i.e. according to feeding guilds) also produced clear discrepancies between TP estimates. TPs obtained with δ15N values of source amino acids (compound-specific isotope analysis) were close to those assessed with macroalgae. An opposite seasonal pattern was found, with significantly lower TPs in winter than in summer for most species, with particularly pronounced differences for lower TP species. We use the observed differences to discuss possible drivers of the diverging TP estimates and the potential ecological implications.

Development of a closed-tube, calcein-based loop-mediated isothermal amplification assay to detect Salmonella spp. in raw meat samples

Foodborne pathogens compromise food safety and public health, and Salmonella spp. are among the major pathogenic bacteria that cause outbreaks worldwide. Proper surveillance through timely and cost-effective detection methods across the food animal production chain is crucial to prevent Salmonella outbreaks and agricultural losses. Traditional culture methods are labor- and resource-intensive, with lengthy turnaround times. Meanwhile, conventional molecular tools, such as PCR and qPCR, are expensive and require technical skills and equipment. Loop-mediated isothermal amplification (LAMP) is a simple, rapid, inexpensive, highly sensitive, and specific molecular assay that does not require expensive equipment. Hence, this study developed and optimized a closed-tube, calcein-based LAMP assay to detect Salmonella using the invA gene and performed evaluation and validation against conventional PCR. The LAMP assay showed high specificity and sensitivity. It showed 10-fold higher sensitivity than conventional PCR, at <1 ng/μL DNA concentrations. Meanwhile, for CFU/mL, LAMP assay showed 1000-fold higher sensitivity than conventional PCR at 4.8 × 103 cells/mL than 4.8 × 107 cells/mL, respectively. For parallel testing of 341 raw meat samples, after conventional culture enrichment (until Rappaport-Vassiliadis broth), the optimized LAMP assay showed 100% detection on all samples while conventional PCR showed 100%, 99.04%, and 96.64% for raw chicken, beef, and pork samples, respectively. Meanwhile, a shortened enrichment protocol involving 3-h incubation in buffered peptone water only, showed lower accuracy in tandem with the optimized LAMP assay ranging from 55 to 75% positivity rates among samples. These suggest that the optimized LAMP assay possesses higher sensitivity over conventional PCR for invA gene detection when coupled with conventional enrichment culture methods. Hence, this assay has potential as a powerful complementary or alternative Salmonella detection method to increase surveillance capacity and protect consumer food safety and public health worldwide.

Evaluation of polyhydroxyalkanoate recovery from food waste by sequencing batch biofilm reactor with high mixed microbial biomass

In this study, the enrichment sequencing batch biofilm reactor (SBBR) and conventional enrichment reactor (SBR) were established, and a new strategy was developed to achieve higher biomass yield and polyhydroxyalkanoate (PHA) production from food waste than those achieved through the conventional method. After the 10th day of an expanded cultivation period, the respective active biomass concentrations in SBR and SBBR were 5.16 and 13.92 g/L, indicating a significant improvement in the biomass yield of mixed microbial culture in the SBBR. The PHA accumulation test revealed that maximum PHA concentration in SBR and SBBR reached 6.60 and 12.70 g/L, respectively, after 80 days of enrichment, indicating that compared to SBR, the SBBR could more effectively improve the PHA accumulation capacity. Meganema, Thauera, and Paracoccus were the dominant PHA-accumulating bacteria in the SBR and SBBR. Additionally, the volumetric productivity of the SBBR was 3.22 g COD/L/d, twice that of the SBR. This study provides new strategies and insights for improving PHA production and reducing the costs of PHA production and reactor investment.

Streamlined Biotinylation, Enrichment and Analysis for Enhanced Plasma Membrane Protein Identification Using TurboID and TurboID-Start Biotin Ligases.

Plasma membrane proteins (PMPs) play pivotal roles in various cellular events and are crucial in disease pathogenesis, making their comprehensive characterization vital for biomedical research. However, the hydrophobic nature and low expression levels of PMPs pose challenges for conventional enrichment methods, hindering their identification and functional profiling. In this study, we presented a novel TurboID-based enrichment approach for PMPs that helped overcoming some of the existing limitations. We evaluated the efficacy of TurboID and its modified form, TurboID-START, in PMP enrichment, achieving efficient and targeted labelling of PMPs without the need for stable cell line generation. This approach resulted reduction in non-specific biotinylation events, leading to improved PMP enrichment and enabled assessment of the subcellular proteome associated with the plasma membrane. Our findings paved the way for studies targeting the dynamic nature of the plasma membrane proteome and aiming to capture transient associations of proteins with the plasma membrane. The novel TurboID-based enrichment approach presented here offers promising prospects for in-depth investigations into PMPs and their roles in cellular processes.

Biomimetic affinity membrane roll column for rapid purification of C-reactive protein

To in-depth explore the action mechanism of C-reactive protein (CRP) and precisely study its signaling pathways, it is essential to acquire high-purity CRP while preserving its intact structure and functionality. In this study, we propose and fabricate a high-density 2-methacryloyloxyethyl phosphorylcholine (MPC)-modified membrane roll column (MPC-MRC) using a surface-initiated atom transfer radical polymerization (SI-ATRP) approach, which can overcome these limitations (long incubation time and low adsorption capacity) of conventional enrichment materials. The MPC-MRC incorporates a high-density 2-hydroxyethyl methacrylate polymer brush to prevent non-specific protein adsorption and multiple MPC polymer brush layers for high-performance enrichment of CRP in the company of calcium ions. Furthermore, the MPC-MRC exhibits high permeability, hydrophilicity, and mechanical strength. Compared to previous technologies, this novel material demonstrates significantly higher CRP binding capacity (310.3 mg/g), shorter processing time (only 15 min), and lower cost (only 12 USD/column). Notably, the MPC-MRC enables fast and effective purification of CRP from both human and rat serum, exhibiting good selectivity, recovery (> 91.3 %), and purity (> 95.2 %). Thus, this proposed purification approach based on MPC-MRC holds great potential for target protein enrichment from complex samples, as well as facilitating in-depth studies of its biological functions.

A magnetic nanoparticle-based microfluidic device fabricated using a 3D-printed mould for separation of Escherichia coli from blood.

Herein, A microfluidic device is described, produced with a 3D-printed master mould that rapidly separates and concentrates Escherichia coli directly from whole blood samples, enabling a reduction in the turnaround time of bloodstream infections (BSIs) diagnosis. Moreover, it promotes the cleansing of the blood samples whose complexity frequently hampers bacterial detection. The device comprises a serpentine mixing channel with two inlets, one for blood samples (spiked with bacteria) and the other for magnetic nanoparticles (MNPs) functionalized with a (bacterio)phage receptor-binding protein (RBP) with high specificity for E. coli. After the magnetic labelling of bacteria throughout the serpentine, the microchannel ends with a trapping reservoir where bacteria-MNPs conjugates are concentrated using a permanent magnet. The optimized sample preparation device successfully recovered E. coli (on average, 66%) from tenfold diluted blood spiked within a wide range of bacterial load (102CFU to 107CFUmL-1). The non-specific trapping, tested with Staphylococcus aureus, was at a negligible level of 12%. The assay was performed in 30min directly from diluted blood thus presenting an advantage over the conventional enrichment in blood cultures (BCs). The device is simple and cheap to fabricate and can be tailored for multiple bacterial separation from complex clinical samples by using RBPs targeting different species. Moreover, the possibility to integrate a biosensing element to detect bacteria on-site can provide a reliable, fast, and cost-effective point-of-care device.

TLSEA: a tool for lncRNA set enrichment analysis based on multi-source heterogeneous information fusion.

Long non-coding RNAs (lncRNAs) play an important regulatory role in gene transcription and post-transcriptional modification, and lncRNA regulatory dysfunction leads to a variety of complex human diseases. Hence, it might be beneficial to detect the underlying biological pathways and functional categories of genes that encode lncRNA. This can be carried out by using gene set enrichment analysis, which is a pervasive bioinformatic technique that has been widely used. However, accurately performing gene set enrichment analysis of lncRNAs remains a challenge. Most conventional enrichment analysis methods have not exhaustively included the rich association information among genes, which usually affects the regulatory functions of genes. Here, we developed a novel tool for lncRNA set enrichment analysis (TLSEA) to improve the accuracy of the gene functional enrichment analysis, which extracted the low-dimensional vectors of lncRNAs in two functional annotation networks with the graph representation learning method. A novel lncRNA-lncRNA association network was constructed by merging lncRNA-related heterogeneous information obtained from multiple sources with the different lncRNA-related similarity networks. In addition, the random walk with restart method was adopted to effectively expand the lncRNAs submitted by users according to the lncRNA-lncRNA association network of TLSEA. In addition, a case study of breast cancer was performed, which demonstrated that TLSEA could detect breast cancer more accurately than conventional tools. The TLSEA can be accessed freely at http://www.lirmed.com:5003/tlsea.

Assessment of the dibenzothiophene desulfurization potential of indigenously isolated bacterial consortium IQMJ-5: a different approach to safeguard the environment

Biodesulfurization is emerging as a valuable technology for the desulfurization of dibenzothiophene (DBT) and its alkylated substitutes, which are otherwise regarded as refractory to other physical and chemical desulfurizing techniques. The inability of the currently identified pure cultures and artificial microbial consortia due to lower desulfurization rate and product inhibition issues has compelled the researcher to look for an alternative solution. Thus, in the present study, an indigenously isolated microbial consortium was employed to tackle the desulfurization issue. Herein, we isolated several kinds of DBT desulfurizing natural microbial consortia from hydrocarbon-contaminated soil samples by conventional enrichment technique. The most effective desulfurizing microbial consortium was sequenced through illumine sequencing technique. Finally, the effect of the products of the desulfurizing pathway (such as 2-hydroxybiphenyl (2-HBP) and sulfate (SO4-2) was evaluated on the growth and desulfurization capability of the isolated consortium. The outcomes of Gibb's assay analysis showed that six isolates followed the "4S" pathway and converted DBT to 2-HBP. Among the isolates, I5 showed maximum growth rate (1.078g/L dry cell weight) and desulfurization activity (about 77% as indicated by HPLC analysis) and was considered for further in-depth experimentation. The analysis of 16S rRNA by high-throughput sequencing approach of the I5 isolate revealed five types of bacterial phyla including Proteobacteria, Bacteroidetes, Firmicutes, Patescibacteria, and Actinobacteria (in order of abundance). The isolate showed significant tolerance to the inhibitory effect of both 2-HBP and SO4-2 and maintained growth in the presence of even about 1.0mM initial concentration of both products. This clearly suggests that the isolate can be an efficient candidate for future in-depth desulfurization studies of coal and other fossil fuels.

Air-assisted liquid-liquid microextraction and enantioselective gas chromatography-tandem mass spectrometry quantification of methyl jasmonate stereoisomers in tea (Camellia sinensis L.)

Different stereoisomers of phytohormones may have different roles in plants while the quantification for stereoisomers still remains a challenge. The chiral separation method for methyl jasmonate (MeJA) in tea (Camellia sinensis L.) was developed by air-assisted liquid-liquid microextraction (AALLME) with enantioselective gas chromatography-mass spectrometry (Es-GC-MS/MS). The Plackett-Burman factorial design was introduced to optimize the multiple parameters of AALLME. Sensitive Es-GC-MS/MS enabled the quantification of the MeJA stereoisomers, which were separated from each other with resolutions of 3.5, 2.7, and 2.5. The linearities were R2 > 0.9971, the limits of detection were 0.08–0.12 ng/mL, the limits of quantification (LOD) were 0.28–0.39 ng/mL, and the recovery range was 80.60–107.03%. The method was applied to analyze the MeJA stereoisomer profiles in tea plants after geometrid feeding and mechanical wounding. (+)-MeJA appeared to be the main bio-active monomer that responded to injury stress. (+)-MeJA similarly increased in tea shoots at only 30 s after geometrid attack or mechanical wounding. The proposed method is superior as air-assisted liquid-liquid microextraction could induce the loss of volatile MeJA in a much shorter time, compared to the conventional enrichment procedure. A novel assay protocol for relative quantification of MeJA stereoisomers in plants responding to different injuries was applied.

MAGNET: A web-based application for gene set enrichment analysis using macrophage data sets.

Characterization of gene lists obtained from high-throughput genomic experiments is an essential task to uncover the underlying biological insights. A common strategy is to perform enrichment analyses that utilize standardized biological annotations, such as GO and KEGG pathways, which attempt to encompass all domains of biology. However, this approach provides generalized, static results that may fail to capture subtleties associated with research questions within a specific domain. Thus, there is a need for an application that can provide precise, relevant results by leveraging the latest research. We have therefore developed an interactive web application, Macrophage Annotation of Gene Network Enrichment Tool (MAGNET), for performing enrichment analyses on gene sets that are specifically relevant to macrophages. Using the hypergeometric distribution, MAGNET assesses the significance of overlapping genes with annotations that were curated from published manuscripts and data repositories. We implemented numerous features that enhance utility and user-friendliness, such as the simultaneous testing of multiple gene sets, different visualization options, option to upload custom datasets, and downloadable outputs. Here, we use three example studies compared against our current database of ten publications on mouse macrophages to demonstrate that MAGNET provides relevant and unique results that complement conventional enrichment analysis tools. Although specific to macrophage datasets, we envision MAGNET will catalyze developments of similar applications in other domains of interest. MAGNET can be freely accessed at the URL https://magnet-winterlab.herokuapp.com. Website implemented in Python and PostgreSQL, with all major browsers supported. The source code is available at https://github.com/sychen9584/MAGNET.

Comparison of BACTEC versus conventional enrichment medium forperitoneal dialysate fluid culture.

Bacterial peritonitis remains a significant cause of mortality in patients on peritoneal dialysis (PD). Early detection of causative organisms and targeted antimicrobial treatment allow for better clinical outcomes. This study compares bacterial growth results from peritoneal dialysate in the BACTEC blood culture system vs. conventional culture. We conducted a prospective study on 46 patients with 63 consecutive episodes of suspected PD peritonitis between August 2020 and August 2021. PD dialysate was simultaneously sent to the laboratory in both BACTEC and sterile bottles. BACTEC bottles were incubated in the BD BACTEC FX system for 5 days. PD effluent transported from the sterile bottles was centrifuged at 3,000 rpm for 15 minutes; the supernatant was inoculated into cooked-meat broth for enrichment. Both incubation methods were extended to 14 days if microorganisms were seen on the Gram-stained smear. Recovery of isolated micro-organisms and time to detection (TTD) were compared. 26 episodes of suspected PD peritonitis based on clinical criteria were identified during the study period. The sensitivity of the BACTEC and the conventional culture methods was 50% and 42.3%, respectively (p=0.45). Seven samples had partial concordance or discordant results. McNemar's χ2-test revealed no statistical difference between either method (p=0.45). TTD was 18.9 ± 24.4 hours via the BACTEC method vs. 37 ± 16.5 hours in conventional cultures (p=0.014). The comparable sensitivities and similar yield in identifying pathogens could be due to the enrichment medium and prolonged incubation period. The shorter TTD for the BACTEC method could facilitate earlier confirmation of bacteriological diagnosis and subsequent treatment strategies.

Rapid detection of Escherichia coli in dairy milk using static headspace-comprehensive two-dimensional gas chromatography.

A new approach is introduced for rapid and reliable bacteria detection in food. Namely, static headspace-comprehensive two-dimensional gas chromatography (HS-GC × GC) with backflushing. The introduced approach provides fast detection of Escherichia coli (E. coli) in enriched ultra-high-temperature processed (UHT) dairy milk. The presence of E. coli may be indicated by detecting microbial volatile organic compounds emanating from test solutions inoculated with E. coli. In the present investigation, HS-GC × GC analysis is preceded by conventional enrichment in nutrient broth and inoculated samples are clearly discernable from controls following as little as 15h sample enrichment. Headspace equilibration for 28min followed by an 8min GC × GC analysis of enriched test solutions reduces time-to-response by approximately one full day compared to conventional culture-based methods. The presence of ethanol, 1-propanol, and acetaldehyde may be used as a putative marker of E. coli contamination in milk and the introduced approach is able to detect single-cell initial bacterial load. Faster, reliable detection of pathogens and/or spoilage microbes in food products is desirable for the food industry. The described approach has great potential to complement the conventional workflow and be utilised for rapid microbial screening of foodstuff.

Review on the chemical reduction modelling of hematite iron ore to magnetite in fluidized bed reactor

Abstract Steel production is considered as one of the major backbones of many economies. Though blast furnace is the primary route of steel production, the industries are willing to alternatives technologies such as the high temperature-controlled conversion of hematite to magnetite. The geological and mineralogical characteristics of the low-grade iron ores possess difficulties in their conventional enrichment. The literature concludes the advantages of high-temperature conversion in terms of easiness in downstream operations caused by decreased hardness and increased magnetic susceptibility of magnetite. The modelling work has been primarily focused on the direct reduction of iron ore to metallic iron. The present compilation discusses the scientific and engineering developments on the reduction-roasting of iron-ore followed by the CFD–DEM modelling and simulation work performed to reduce iron ore to magnetite. It provides a comprehensive review of the experimental and industrial progress done in the area.

Mutation-specific reporter for optimization and enrichment of prime editing

Prime editing is a versatile genome-editing technique that shows great promise for the generation and repair of patient mutations. However, some genomic sites are difficult to edit and optimal design of prime-editing tools remains elusive. Here we present a fluorescent prime editing and enrichment reporter (fluoPEER), which can be tailored to any genomic target site. This system rapidly and faithfully ranks the efficiency of prime edit guide RNAs (pegRNAs) combined with any prime editor variant. We apply fluoPEER to instruct correction of pathogenic variants in patient cells and find that plasmid editing enriches for genomic editing up to 3-fold compared to conventional enrichment strategies. DNA repair and cell cycle-related genes are enriched in the transcriptome of edited cells. Stalling cells in the G1/S boundary increases prime editing efficiency up to 30%. Together, our results show that fluoPEER can be employed for rapid and efficient correction of patient cells, selection of gene-edited cells, and elucidation of cellular mechanisms needed for successful prime editing.

Isolation and Characterization of Biosurfactant-producing Alcaligenes sp. YLA11 and its Diesel Degradation Potentials

This study aimed to isolate and identify biosurfactant producing and diesel alkanes degrading bacteria. For this reason, bacteria isolated from the diesel contaminated site were screened for their potential to produce biosurfactants and degrade diesel alkanes. Primary selection of diesel degraders was carried out by using conventional enrichment culture technique where 12 bacterial strains were isolated based on their ability to grow on minimal media supplemented with diesel as sole carbon source, which was followed by qualitative screening methods for potential biosurfactant production. Isolate B11 was the only candidate that shows positive signs for drop collapse, foaming, haemolytic test, oil displacement of more than 22 ± 0.05 mm, and emulsification (E24) of 14 ± 0.30%. The effect of various culture parameters (incubation time, diesel concentration, nitrogen source, pH and temperature) on biodegradation of diesel was evaluated. The optimum incubation time was confirmed to be 120 days for isolates B11, the optimum PH was confirmed as 8.0 for the isolate, Similarly, the optimum temperature was confirmed as 35oC. In addition, diesel oil was used as the sole carbon source for the isolates. The favourable diesel concentration was 12.5 % (v/v) for the isolate. The isolate has shown degradative ability towards Tridecane (C13), dodecane, 2, 6, 10-trimethyl- (C15), Tetradecane (C14), 2,6,10-Trimethyltridecane (C16), Pentadecane (C15). It degraded between 0.27% - 9.65% individual diesel oil alkanes. The strain has exhibited the potential of degrading diesel oil n-alkanes and was identified as Alcaligenes species strain B11 (MZ027604) using the 16S rRNA sequencing.

ON-rep-seq as a rapid and cost-effective alternative to whole-genome sequencing for species-level identification and strain-level discrimination of Listeria monocytogenes contamination in a salmon processing plant.

Identification, source tracking, and surveillance of food pathogens are crucial factors for the food‐producing industry. Over the last decade, the techniques used for this have moved from conventional enrichment methods, through species‐specific detection by PCR to sequencing‐based methods, whole‐genome sequencing (WGS) being the ultimate method. However, using WGS requires the right infrastructure, high computational power, and bioinformatics expertise. Therefore, there is a need for faster, more cost‐effective, and more user‐friendly methods. A newly developed method, ON‐rep‐seq, combines the classical rep‐PCR method with nanopore sequencing, resulting in a highly discriminating set of sequences that can be used for species identification and also strain discrimination. This study is essentially a real industry case from a salmon processing plant. Twenty Listeria monocytogenes isolates were analyzed both by ON‐rep‐seq and WGS to identify and differentiate putative L. monocytogenes from a routine sampling of processing equipment and products, and finally, compare the strain‐level discriminatory power of ON‐rep‐seq to different analyzing levels delivered from the WGS data. The analyses revealed that among the isolates tested there were three different strains. The isolates of the most frequently detected strain (n = 15) were all detected in the problematic area in the processing plant. The strain level discrimination done by ON‐rep‐seq was in full accordance with the interpretation of WGS data. Our findings also demonstrate that ON‐rep‐seq may serve as a primary screening method alternative to WGS for identification and strain‐level differentiation for surveillance of potential pathogens in a food‐producing environment.

Degradation Potentials Of Tropical Soil Bacteria On Detergents

Detergents are chemicals of high environmental importance owing to their production volumes. They are mainly released into the environment through wastewater pathway and it could severely affect the soil environment. In this study, we examined the degradation potentials of soil bacteria in liquid culture media induced with detergents. Using conventional enrichment methods, via contaminated soil slurry enrichment with selected alkyl-benzene sulphonates (detergents), we obtained pure bacteria species capable of using alkyl-benzene sulphonates as the sole source of carbon and energy. From the morphological and biochemical characterization and comparison with respect to the standard reference organisms, the bacteria isolates were presumably Corynebacterium, Pseudomonas, and Bacillus species. Different concentrations 5.0, 10.0 15.0, and 20.0 w/v of the branded detergents were prepared as sole carbon and energy and screened against our bacteria species to determine their physiological gradient fluxes after 96hours of incubation. Data obtained showed an increase in Optical density (OD) as well as increases in pH flux values. The mean OD data obtained ranged between 0.017- 0.818, with a pH of 7.47-8.95. From this study, tropical soils possess unique bacteria species capable of utilizing alkyl-benzene sulphonates (detergents).

Rapid detection for low numbers of Escherichia coli O157:H7 by real-time PCR in cabbage using a combination of filtration, short microbial enrichment, and DNA concentration within 4 h

Methodsfocused on conventional foodborne pathogen detection by selective media are cumbersome and require long time for culture enrichment. Several rapid tests have been developed for the detection of Escherichia coli O157:H7 in the food industry. However, the E. coli O157:H7 method takes very long and requires more than one day to achieve the detection threshold using PCR based enrichment in food. We reported a combination of filtration-based accelerated sample concentration methods to detect <9 CFU/25g of E. coli O157:H7 in cabbage. Filtration, short concentration, as well as DNA concentration contribute to making the detection level the target for real-time PCR analysis. The short enrichment was performed after the filtration, which was shorter than the conventional enrichment method. It was concluded that 0–7 CFU/25 g of E. coli O157:H7 was detected within 4 h after 2 h of incubation following filtration. This combination of filter-based enrichment methods is a faster and more efficient way for reaching the desired bacterial concentration compared to the conventional culture enrichment steps, and can significantly reduce the time required to obtain assay results.

Effect of coaxial oxygen enrichment on three different coals and their blends

ABSTRACT Mathematical models appear as very attractive alternatives in blast furnace studies. Therefore, a three-dimensional model is described and validated to simulate the flow and combustion of binary coal blends under simplified blast furnace conditions. The present article aims to analyse the performance of different coals and their blends for conventional and coaxial oxygen enrichment methods. Among the simulated coals, Coal C, which combines one of the smallest particle sizes with one of the highest volatile matter contents, presented the highest burnout and average temperature values. Coaxial oxygen enrichment showed a negative effect on coal combustibility in the cases with 26.9% of O2. This is explained by the large amount of gas being injected by the coaxial lance, resulting in a cooling effect and particle concentration. Also, blending coal A with coal B resulted in an improvement of burnout for both coals, because of the synergetic effect caused by their combustion.

Fast and Highly Efficient Affinity Enrichment of Azide-A-DSBSO Cross-Linked Peptides.

Cross-linking mass spectrometry is an increasingly used, powerful technique to study protein–protein interactions or to provide structural information. Due to substochiometric reaction efficiencies, cross-linked peptides are usually low abundance. This results in challenging data evaluation and the need for an effective enrichment. Here we describe an improved, easy to implement, one-step method to enrich azide-tagged, acid-cleavable disuccinimidyl bis-sulfoxide (DSBSO) cross-linked peptides using dibenzocyclooctyne (DBCO) coupled Sepharose beads. We probed this method using recombinant Cas9 and E. coli ribosome. For Cas9, the number of detectable cross-links was increased from ∼100 before enrichment to 580 cross-links after enrichment. To mimic a cellular lysate, E. coli ribosome was spiked into a tryptic HEK background at a ratio of 1:2–1:100. The number of detectable unique cross-links was maintained high at ∼100. The estimated enrichment efficiency was improved by a factor of 4–5 (based on XL numbers) compared to enrichment via biotin and streptavidin. We were still able to detect cross-links from 0.25 μg cross-linked E. coli ribosomes in a background of 100 μg tryptic HEK peptides, indicating a high enrichment sensitivity. In contrast to conventional enrichment techniques, like SEC, the time needed for preparation and MS measurement is significantly reduced. This robust, fast, and selective enrichment method for azide-tagged linkers will contribute to mapping protein–protein interactions, investigating protein architectures in more depth, and helping to understand complex biological processes.