Publications by authors named "Zhinan Xu"

Phage contamination poses a significant threat to industrial fermentation, leading to substantial economic losses. Virulent T-even type phages (T2/T4/T6) represent particularly concerning biological hazards in fermentation systems. This paper developed a novel CRISPR/Cas12a-based system integrated with recombinase polymerase amplification (RPA), enabling ultrasensitive identification of T-even type phages.

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Argonaute (Ago), a programmable nuclease, has recently emerged as a promising tool for nucleic acid detection. To achieve higher sensitivity, a nucleic acid amplification step is often introduced into the Ago-based detection system, leading the process suffered from the issues of temperature compatibility and device complexity. To address these limitations, integrating multiple reactions within a portable temperature control device shows significant potential to streamline the development and practical application of these systems.

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Efficient multi-gene expression in Escherichia coli is critical for advancing metabolic engineering and synthetic biology. However, existing strategies for combinatorial optimization remain labor-intensive and low-throughput. In addressing this challenge, a high-throughput platform was developed, encompassing the engineering of standardized genetic elements (promoters and 5' UTRs) with fluorescent reporters (e.

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S-adenosyl-L-methionine (SAM) is an important intermediate metabolite and widely used in the treatment of liver disease, arthritis, and depression. In this work, a whole-cell catalysis strategy was employed to enhance SAM production by combining the SAM biosynthetic pathway with an adenosine triphosphate (ATP) regeneration system in Specifically, the , , and genes were previously introduced into the genome of the host strain. We then confirmed the availability of the ATP regeneration system under the condition of adding adenosine monophosphate (AMP) and acetyl phosphate (ACP) as supplements.

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There is a growing interest in establishing yeast as a cell factory for terpenoid production. Given the hydrophobicity of many terpenoids, expanding the intracellular storage pool is an effective strategy to improve titers. In this study, the storage capacity was enhanced by increasing yeast cell size through the knockout of EST1 and SSN8.

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Argonaute proteins (Agos), endowed with the capacity to cleave DNA or RNA under the guidance of small nucleic acid guides, have emerged as versatile biotechnological tools. This study endeavored to characterize a novel thermophilic Argonaute protein from Thermus brockianus (TbAgo), revealing its proficiency as a DNA-guided DNA endonuclease. Demonstrating high catalytic efficiency and precision at 65 °C, TbAgo possessed compatibility with loop-mediated isothermal amplification (LAMP) method, whose optimal temperature is also around 65 °C.

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Integrating recombinase-polymerase amplification (RPA) with CRISPR-Cas12a holds significant potential to simplify and improve nucleic acid diagnostic procedures. However, current strategies face limitations, such as complexity, reduced efficiency, and potential compromises in Cas12a activity. In response, we developed a NAzyme-triggered quilibrium transfer with a elf-activated SPR-Cas12a iosnso (DESCRIBER) for integrated nucleic acid detection.

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Article Synopsis
  • Lithium is an emerging contaminant with limited data on its effects in soil-plant systems, prompting research using maize, wheat, pea, and water spinach to evaluate its pollution characteristics and ecotoxicological impacts.
  • The study found that lithium is highly mobile in soils, often persisting in an amorphous state, and can significantly enhance growth parameters of certain plants when present in specific concentrations.
  • Water spinach was identified as particularly effective in accumulating lithium and exhibiting tolerance to its stress, making it a viable option for phytoremediation and contributing to understanding lithium's role in environmentally sustainable practices.
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Plant natural products (PNPs) exhibit a wide range of biological activities and have essential applications in various fields such as medicine, agriculture, and flavors. Given their natural limitations, the production of high-value PNPs using microbial cell factories has become an effective alternative in recent years. However, host metabolic burden caused by its massive accumulation has become one of the main challenges for efficient PNP production.

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  • 7-Dehydrocholesterol (7-DHC) is a key precursor for vitamin D and is commonly found in many organisms, but current production methods aren’t meeting industrial needs.
  • This study successfully enhanced the production of 7-DHC in Saccharomyces cerevisiae (yeast) by increasing specific gene copies and optimizing the yeast’s cellular processes.
  • The research demonstrated a remarkable 26-fold increase in 7-DHC production, achieving the highest recorded levels of 640.77 mg/L in shake flasks and 4.28 g/L in larger fermentors, paving the way for efficient and large-scale production applications.
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While sanguinarine has gained recognition for antimicrobial and antineoplastic activities, its complex conjugated structure and low abundance in plants impede broad applications. Here, we demonstrate the complete biosynthesis of sanguinarine and halogenated derivatives using highly engineered yeast strains. To overcome sanguinarine cytotoxicity, we establish a splicing intein-mediated temperature-responsive gene expression system (SIMTeGES), a simple strategy that decouples cell growth from product synthesis without sacrificing protein activity.

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Monoterpene indole alkaloids (MIAs) are a group of plant-derived natural products with high-value medicinal properties. However, their availability for clinical application is limited due to challenges in plant extraction. Microbial production has emerged as a promising strategy to meet the clinical demands for MIAs.

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β-Elemene, an active ingredient found in medicinal plants like turmeric and zedoary, is a sesquiterpene compound with antitumor activity against various cancers. However, its current mode of production through plant extraction suffers from low efficiency and limited natural resources. Recently, there has been an increased interest in establishing microbial cell factories to produce germacrene A, which can be converted to β-elemene by a one-step reaction in vitro.

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l-glutathione (GSH) is an important tripeptide compound with extensive applications in medicine, food additives, and cosmetics industries. In this work, an innovative whole-cell catalytic strategy was developed to enhance GSH production by combining metabolic engineering of GSH biosynthetic pathways with an adenosine-based adenosine triphosphate (ATP) regeneration system in Escherichia coli. Concretely, to enhance GSH production in E.

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Article Synopsis
  • Biotin, or vitamin H/B, is essential for metabolizing fatty acids, amino acids, and carbohydrates and is important for various applications in food and medicine.
  • Humans and animals cannot produce biotin on their own and must obtain it from diet and gut bacteria, while microorganisms and plants can synthesize it.
  • The review covers methods of biotin production, including chemical synthesis and sustainable microbial alternatives, and discusses ways to enhance production through mutation, genetic engineering, and optimization for future industrial use.
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Peroxisomal compartmentalization has emerged as a highly promising strategy for reconstituting intricate metabolic pathways. In recent years, significant progress has been made in the peroxisomes through harnessing precursor pools, circumventing metabolic crosstalk, and minimizing the cytotoxicity of exogenous pathways. However, it is important to note that in methylotrophic yeasts (e.

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The fast growth increases in energy use and greenhouse gas emissions in China's tourism industry. This article assessed the carbon emissions of tourist Chengdu's traffic patterns and how they are expected to change between 2005 and 2021 and explains why tourism carbon decoupling is important for sustainable tourism development. In order to investigate how carbon emissions from tourism may expand without necessarily increasing in tandem with GDP and the variables that influence it, the Tapir model and the LMDI (logarithmic mean Divisia index) method were used.

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Vinblastine has been used clinically as one of the most potent therapeutics for the treatment of several types of cancer. However, the traditional plant extraction method suffers from unreliable supply, low abundance, and extremely high cost. Here, we use synthetic biology approach to engineer for de novo biosynthesis of vindoline and catharanthine, which can be coupled chemically or biologically to vinblastine.

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The CRISPR Cas system, as a novel nucleic acid detection tool, is often hindered by cumbersome experimental procedures, complicated reagent transfer processes, and associated aerosol pollution risks. In this study, an integrated nucleic acid detection platform named "up and down chip" was developed, which combined RT-RAA technology for nucleic acid amplification, DNase-dead Cas12a-modified magnetic beads for specific recognition of target nucleic acid, and HRP-TMB chromogenic reaction for signal output in different chambers of a single microfluidic chip. The magnetic beads were migrated in an up-and-down manner between different chambers through magnetic driving, achieving a "sample-in, result-out" detection mode.

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While there are several genome editing techniques available, few are suitable for dynamic and simultaneous mutagenesis of arbitrary targeted sequences in prokaryotes. Here, to address these limitations, we present a versatile and multiplex retron-mediated genome editing system (REGES). First, through systematic optimization of REGES, we achieve efficiency of ∼100%, 85 ± 3%, 69 ± 14% and 25 ± 14% for single-, double-, triple- and quadruple-locus genome editing, respectively.

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Article Synopsis
  • Foodborne pathogens present significant food safety issues, with a specific virulent bacterium causing major public health concerns.
  • Traditional detection methods for this bacterium are often slow, labor-intensive, and require specialized equipment and trained personnel.
  • The paper introduces a new detection platform using CRISPR/Cas12a, allowing for rapid, accurate, and visible identification of the pathogen, making it user-friendly and suitable for point-of-care testing in food safety.
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The impact of antibiotics on methane (CH) release from sediment involves both CH production and consumption processes. However, most relevant studies lack a discussion of the pathways by which antibiotics affect CH release and do not highlight the role played by the sediment chemical environment in this influence mechanism. Here, we collected field surface sediments and grouped them with various antibiotic combination concentration gradients (50, 100, 500, 1000 ng g) under a 35-day indoor anaerobic constant temperature incubation.

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The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has promoted the development of nucleic acid diagnosis technology. Several platforms with isothermal amplification methods have achieved sensitive and specific detection of SARS-CoV-2. However, they still suffer from complicated operations, delicate instruments, and unintuitive signal output modes.

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Lithium is an emerging environmental contaminant in the current low-carbon economy, but little is known about its influences on soil invertebrates. In this work, earthworm Eisenia fetida was exposed to soils treated with different levels of lithium for 7 d, and multiple ecotoxicological parameters were evaluated. The results showed that mortality was dose-dependent and lithium's median lethal content (LC) to earthworm was respectively 865.

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Triacetic acid lactone (TAL) is a promising renewable platform polyketide with broad biotechnological applications. In this study, we constructed an engineered strain for the production of TAL. We first introduced a heterologous TAL biosynthetic pathway by integrating the 2-pyrone synthase encoding gene from ().

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