Engineering modular enzyme assembly: synthetic interface strategies for natural products biosynthesis applications.

Covering: 2020 to 2025Natural products remain indispensable sources of therapeutic and bioactive compounds, yet traditional discovery strategies are constrained by compound rediscovery. Modular biosynthetic enzymes, such as type I polyketide synthases (PKSs) and type A non-ribosomal peptide synthetases (NRPSs), offer promising platforms for combinatorial biosynthesis owing to their programmable architectures. However, practical implementation is frequently limited by inter-modular incompatibility and domain-specific interactions.

Regulatory orchestration of FK506 biosynthesis in NRRL 18488 revealed through systematic analysis.

NRRL 18488, the primary producer of the immunosuppressant FK506, was analyzed to elucidate regulatory features of secondary metabolism. Completion of its 7.9-Mb linear genome enabled accurate re-annotation of the FK506 biosynthetic gene cluster (BGC).

Air-Stable Mid-Infrared Sensitive Cation-Exchanged Silver-Doped Mercury Telluride Nanocrystal.

We present an air-stable mid-infrared (mid-IR) Ag-doped HgTe (Ag-HgTe) colloidal quantum dots (CQDs) synthesized by a newly developed cation-exchange (CE) method in solution phase and mid-IR diode sensors fabricated with the as-synthesized Ag-HgTe quantum dots (QDs). The cation-exchanged p-doped Ag-HgTe CQDs are used for the p-n junction formation with a n-doped HgTe CQDs. Surprisingly, the Ag-HgTe CQDs sustain the optical and physical properties in the colloidal phase under ambient conditions for 900 days.

Relationship Between Harvesting Efficiency and Filament Morphology in Gomont.

, a filamentous cyanobacterium, exhibits morphological variability influenced by biotic and abiotic factors. We investigated the effect of sodium ion concentration on filament length, growth, and harvest efficiency. Increasing the sodium concentration from 0.

Engineered CRISPR-Cas9 for Streptomyces sp. genome editing to improve specialized metabolite production.

The CRISPR-Cas9 system has frequently been used for genome editing in Streptomyces; however, cytotoxicity, caused by off-target cleavage, limits its application. In this study, we implement innovative modification to Cas9, strategically addressing challenges encountered during gene manipulation using Cas9 within strains possessing high GC content genome. The Cas9-BD, a modified Cas9 with the addition of polyaspartate to its N- and C-termini, is developed with decreased off-target binding and cytotoxicity compared with wild-type Cas9.

Optimized Extraction of Sargahydroquinoic Acid, Major Bioactive Substance, from Using Response Surface Methodology.

Sargahydroquinoic acid (SHQA), a bioactive compound found in certain species, exhibits significant health benefits. This study optimized the extraction of SHQA from using response surface methodology (RSM) and evaluated its antioxidant effects through in vitro and in vivo assays. A Box-Behnken design (BBD) was effectively employed to investigate the effects of incubation temperature, time, and ethanol concentration on SHQA yield, achieving a high coefficient of determination (R = 0.

Screening Method to Identify Watermelon Cultivars Resistant to Acidovorax citrulli, the Cause of Bacterial Fruit Blotch.

Acidovorax citrulli is a causative pathogen for bacterial fruit blotch (BFB) in Cucurbitaceae, including watermelon. The most effective method to control this plant disease is to cultivate resistant cultivars. Herein, this study aimed to establish an efficient screening method to determine the resistance of watermelon cultivars against A.

Silver Telluride Colloidal Quantum Dot Solid for Fast Extended Shortwave Infrared Photodetector.

Extended shortwave infrared (eSWIR) photodetectors that employ solution-processable semiconductors have attracted attention for use in applications such as ranging, night vision, and gas detection. Colloidal quantum dots (CQDs) are promising materials with facile bandgap tunability across the visible-to-mid-infrared wavelengths. However, toxic elements, such as Hg and Pb, and the slow response time of CQD-based IR photodetectors, limit their commercial viability.

Halide-Driven Synthetic Control of InSb Colloidal Quantum Dots Enables Short-Wave Infrared Photodetectors.

In the III-V family of colloidal quantum dot (CQD) semiconductors, InSb promises access to a wider range of infrared wavelengths compared to many light-sensing material candidates. However, achieving the necessary size, size-dispersity, and optical properties has been challenging. Here the synthetic challenges associated with InSb CQDs are investigated and it is found that uncontrolled reduction of the antimony precursor hampers the controlled growth of CQDs.

Engaging social activities prevent stroke and myocardial infraction by raising awareness of warning symptoms: A cross-sectional survey study.

Background: Stroke and myocardial infarction (MI) are medical emergencies, and early treatment within the golden hour is crucial for good prognosis. Adequate knowledge about the warning symptoms can shorten the onset-to-door time. Various factors affect the level of awareness, including social activity.

Photometric determination of peracetic acid by reaction with potassium iodide solution.

Peracetic acid (PAA) is a strong oxidizing agent and is considered an ideal disinfectant because of its excellent disinfecting effect at low concentration, low corrosiveness, and relatively low cost. Commercially available PAA solution is a mixture of PAA, acetic acid, and hydrogen peroxide. However, PAA naturally decomposes faster than hydrogen peroxide.

Association between Breastfeeding and Restrictive Spirometric Pattern in Women Aged over 40 Years: A Cross-Sectional Study.

Objectives: Restrictive spirometric pattern (RSP) has a prevalence of 5.4−9.2% and is associated with various respiratory symptoms, comorbidities, and increased mortality.

A simple spectrophotometric determination of hydrogen peroxide solution via spectral delta from redox reaction with sodium hypochlorite.

Hydrogen peroxide (HO) is widely used in the synthesis of organic chemicals, bleaching of paper pulp, and the treatment of wastewater and as a food additive, important mediator of redox processes in natural water, and a disinfectant. However, HO stock solution is unstable and slowly decomposes when exposed to, for example, light, elevated temperatures, or metal compounds. Therefore, the ability to measure the exact concentration of HO stock solution is important for its proper use in diverse applications.

System-Level Analysis of Transcriptional and Translational Regulatory Elements in .

Bacteria belonging to have the ability to produce a wide range of secondary metabolites through a shift from primary to secondary metabolism regulated by complex networks activated after vegetative growth terminates. Despite considerable effort to understand the regulatory elements governing gene expression related to primary and secondary metabolism in , system-level information remains limited. In this study, we integrated four multi-omics datasets from NBRC 13350: RNA-seq, ribosome profiling, dRNA-seq, and Term-Seq, to analyze the regulatory elements of transcription and translation of differentially expressed genes during cell growth.

Midwavelength Infrared Colloidal Nanowire Laser.

Realizing bright colloidal infrared emitters in the midwavelength infrared (or mid-IR), which can be used for low-power IR light-emitting diodes (LEDs), sensors, and deep-tissue imaging, has been a challenge for the last few decades. Here, we present colloidal tellurium nanowires with strong emission intensity at room temperature and even lasing at 3.6 μm (ω) under cryotemperature.

as Microbial Chassis for Heterologous Protein Expression.

Heterologous production of recombinant proteins is gaining increasing interest in biotechnology with respect to productivity, scalability, and wide applicability. The members of genus have been proposed as remarkable hosts for heterologous production due to their versatile nature of expressing various secondary metabolite biosynthetic gene clusters and secretory enzymes. However, there are several issues that limit their use, including low yield, difficulty in genetic manipulation, and their complex cellular features.

Improving Biosensors by the Use of Different Nanomaterials: Case Study with Microcystins as Target Analytes.

The eutrophication of lakes and rivers without adequate rainfall leads to excessive growth of cyanobacterial harmful algal blooms (CyanoHABs) that produce toxicants, green tides, and unpleasant odors. The rapid growth of CyanoHABs owing to global warming, climate change, and the development of rainforests and dams without considering the environmental concern towards lakes and rivers is a serious issue. Humans and livestock consuming the toxicant-contaminated water that originated from CyanoHABs suffer severe health problems.

A pretreatment-free electrical capacitance biosensor for exosome detection in undiluted serum.

The exosome is considered a useful biomarker for the early diagnosis of cancer. However, pretreatment of samples used in diagnosis is time-consuming. Herein, we fabricated a capacitance-based electrical biosensor that requires no pretreatment of the sample; it is composed of a DNA aptamer/molybdenum disulfide (MoS) heterolayer on an interdigitated micro-gap electrode (IDMGE)/printed circuit board (PCB) system for detecting exosomes in an undiluted serum sample.

Re-classification of strains and mining secondary metabolite biosynthetic gene clusters.

species have attracted considerable interest as a reservoir of medically important secondary metabolites, which are even diverse and different between strains. Here, we reassess ten strains by presenting the highly resolved classification, using 16S rRNA sequencing, MALDI-TOF MS protein profiling, and whole-genome sequencing. The results revealed that seven of the ten strains were misclassified as .

Fabrication of MERS-nanovesicle biosensor composed of multi-functional DNA aptamer/graphene-MoS nanocomposite based on electrochemical and surface-enhanced Raman spectroscopy.

Middle East respiratory syndrome coronavirus (MERS-CoV) is one of the most harmful viruses for humans in nowadays. To prevent the spread of MERS-CoV, a valid detection method is highly needed. For the first time, a MERS-nanovesicle (NV) biosensor composed of multi-functional DNA aptamer and graphene oxide encapsulated molybdenum disulfide (GO-MoS) hybrid nanocomposite was fabricated based on electrochemical (EC) and surface-enhanced Raman spectroscopy (SERS) techniques.

Extended Short-Wavelength Infrared Photoluminescence and Photocurrent of Nonstoichiometric Silver Telluride Colloidal Nanocrystals.

Demands on nontoxic nanomaterials in the short-wavelength infrared (SWIR) have rapidly grown over the past decade. Here, we present the nonstoichiometric silver chalcogenide nanocrystals of AgTe ( > 2) and AgTe/AgS CQDs with a tunable bandgap across the SWIR region. When the atomic percent of the metal and chalcogenide elements are varied, the emission frequency of the excitonic peak is successfully extended to 2.

Recent Advances in CRP Biosensor Based on Electrical, Electrochemical and Optical Methods.

C-reactive protein (CRP) is an acute-phase reactive protein that appears in the bloodstream in response to inflammatory cytokines such as interleukin-6 produced by adipocytes and macrophages during the acute phase of the inflammatory/infectious process. CRP measurement is widely used as a representative acute and chronic inflammatory disease marker. With the development of diagnostic techniques measuring CRP more precisely than before, CRP is being used not only as a traditional biomarker but also as a biomarker for various diseases.

Beyond the Bandgap Photoluminescence of Colloidal Semiconductor Nanocrystals.

Intraband transitions of colloidal semiconductor nanocrystals, or the electronic transitions occurring in either the conduction band or valence band, have recently received considerable attention because utilizing the intraband transitions provides new approaches for applications such as photodetectors, imaging, solar cells, lasers, and so on. In the past few years, it has been revealed that observing the intraband transition is not limited for temporal measurement such as ultrafast spectroscopy but available for steady-state measurement even under ambient conditions with the help of self-doped semiconductor nanocrystals. Considering the large absorption coefficient of the steady-state intraband transition comparable to that of the bandgap transition, the use of the intraband transition will be promising for both fundamental and application studies.

Fabrication of electrochemical biosensor consisted of multi-functional DNA structure/porous au nanoparticle for avian influenza virus (H5N1) in chicken serum.

Avian influenza virus (AIV) is one of the most harmful pathogens to living things due to its fast infection, various mutations, and dangerous symptoms. In this study, we fabricated a label-free AIV H5N1 biosensor composed of multi-functional DNA structure on a porous Au nanoparticles (pAuNPs) fabricated electrode using the electrochemical (EC) technique. As a multi-functional bioprobe, the DNA 3 way-junction (3WJ) was introduced.