Deep metagenomic insights into the formation characteristics of the resistome in Pristine Saline Lakes.

The clinical translation of adeno-associated virus (AAV)-based gene therapies is often hindered by nonselective tissue transduction, off-target uptake by nontarget cells, and unintended toxicity to healthy tissues. To overcome these challenges, we previously developed a site-specific AAV capsid engineering strategy involving the incorporation of an azide-bearing unnatural amino acid (NAEK) into defined capsid positions, enabling precise, bioorthogonal conjugation of targeting ligands. In this study, we applied this approach to generate a series of folate receptor α (FRα)-targeted AAV2 vectors through covalent tethering of folic acid (FA) at specific capsid residues. FA conjugation at residues S264 + 1 and Q325 significantly enhanced FRα-mediated transduction, yielding a 3-5-fold increase in gene transfer efficiency in FRα-positive tumor cells. Structure-activity relationship analysis revealed that transduction selectivity is governed not only by ligand-receptor binding affinity but also by the spatial location of the conjugation site, which influences competition with the native AAV receptor (AAVR). Importantly, this modular conjugation platform allows for facile replacement of ligands, enabling the rational design of receptor-directed AAV vectors for targeted and cell-specific gene therapy. These findings provide mechanistic insights into capsid-receptor interactions and establish a flexible strategy for precision engineering of AAV-based delivery systems.

Decoding the microplastic Micro-interface: a complex Web of gene transfer and pathogenic threats in wastewater.

The identification of neuronal circuits and their specific functions in behavior and disease is essential for understanding the mammalian brain. A promising technique to advance this goal involves the use of lentiviral vectors for specific gene transfer into specific brain circuit. The vesicular stomatitis virus glycoprotein (VSV-G) pseudotyped lentiviral vectors can introduce genes in neurons at the injection sites. Retrograde lentiviral vectors, such as highly efficient retrograde gene transfer (HiRet) and neuron-specific retrograde gene transfer (NeuRet) vectors, enable the delivery of genetic materials into neurons based on their axonal projections. These lentiviral vectors represent a powerful genetic tool for neuroscience research. Here, we describe a step-by-step experimental procedure for injecting viral vectors into target brain areas using the basal ganglia circuit as example in mice to map their functional properties. This methodology, which integrates local and retrograde gene transfer with optogenetic manipulation, offers a robust framework for investigating the functional organization of neuronal circuits. In demonstrating this approach, this chapter aims to guide researchers to apply these techniques to study brain functions and disorders of interest.

Dual-pathway inhibition of antibiotic resistance genes by ferrate (Fe(VI)): Oxidative inactivation and genetic mobility impairment in anaerobically digested sludge.

Lentivirus vectors are capable of efficient gene transfer to nondividing cells, in addition to dividing cells. Therefore, lentivirus vectors can also be used for gene transfer into dormant stem cells in the postnatal and adult brains of experimental animals, many of which have ceased cell division. For example, it is known that neural stem cells (NSCs) are present around the lateral ventricle and in the dentate gyrus of the hippocampus in the postnatal and adult brain and continue to give rise to neurons. However, the majority of these NSCs are considered to be quiescent, and lentivirus vectors are an important tool to enable gene transfer to dormant stem cells. Lentivirus vectors are also capable of multiple infection of the same cells, making them an important option for experiments requiring high gene expression levels. By selecting transduced cells after infection with high titer lentivirus vectors and repeating infection, genes that are difficult to express or gene sequences that require high copy number can be introduced into cells with high efficiency. In this chapter, we present examples of gene transfer to NSCs localized at the hippocampal dentate gyrus in mice using lentivirus vectors and establishment of stable transgenic NSC lines by multiple infections.

The brain controls various physiological functions through a complex network of neural circuits. To elucidate the function of individual neural circuits, it is necessary to perform both the anatomical mapping and functional manipulation of these circuits in living animals. Our understanding of the neural mechanisms underlying physiological functions has recently been advanced by technological innovations in optical approaches to manipulate neural activity and viral vector systems for in vivo gene delivery. The application of optogenetic tools to neurons in the brain facilitates the selective and reversible manipulation of neuronal activity with millisecond precision using light-sensitive proteins. Regarding gene transfer into specific neural circuits, the lentiviral system for highly efficient retrograde gene transfer (HiRet) offers the advantages of neural circuit selectivity and stable transgene expression. The combined approach of optogenetic tools and HiRet vectors allows the cell type-specific manipulation of neuronal activity and animal behavior with high spatial and temporal precision. I herein describe a protocol for manipulating the activity of neural circuits involved in the control of thirst and salt appetite in freely moving animals as an example of the optogenetic approach using HiRet vectors. This application will be widely utilized to characterize individual neural circuits underlying physiological functions.

Coordinated horizontal transfer of multiple genes assembles a carotenoid biosynthesis pathway in aphids.

Microbial dynamics in a swine wastewater treatment plant and prediction of potential hosts of antibiotic resistance genes.

Decoding anammox granulation: Microbial interactions promote granule formation and indirectly shape antibiotic resistance gene dissemination.

In recent years, direct reprogramming methods have attracted attention as they can bypass the immature stem cell state and directly induce the desired cell type by introducing key transcription factors into somatic cells. This technique offers advantages such as shorter induction times compared to inducing the desired cells from induced pluripotent stem cells. Furthermore, this approach enables the provision of the requisite cell types to patients requiring treatment without eliciting an immune rejection response. Microglia, the resident immune cells of the central nervous system, exhibit high proliferative and regenerative capacities, allowing them to repopulate even after almost complete depletion. In response to injury, microglia accumulate in damaged brain regions and become the primary cell type that forms the glial scar. Given these properties, microglia are promising candidates for direct reprogramming into neurons in the injured area without depleting cell sources. This chapter outlines a protocol for directly reprogramming cortical microglia into neurons, utilizing primary culture and lentiviral-mediated gene transfer techniques.

Lentiviral (LV) vectors derived from human immunodeficiency virus type 1 (HIV-1) mediate efficient gene transfer into various cell types, including neuronal, glial, and neural stem cells in the central nervous system. The HIV-1-based LV vectors commonly used are self-inactivating and pseudotyped with a variety of viral envelope glycoproteins. Pseudotyping with vesicular stomatitis virus glycoprotein (VSV-G) confers broad tropism to wide variety of cells and enhances vector stability of the vectors. Pseudotyping with other glycoproteins alters the tropism. In particular, the use of rabies virus glycoprotein (RV-G) or fusion glycoproteins (FuGs) consisting of VSV-G and RV-G segments increases the efficiency of retrograde gene delivery into neuronal cells. The LV vector strategy provides useful approaches to genetic manipulation of specific neural pathways for elucidating the structure and function of neural circuits, and also to genome-wide screening of key molecules and gene regulatory elements in development and survival of the nervous system. Such a strategy also provides a powerful tool for clinical applications aimed at gene therapy for neurological and neurodegenerative diseases as well as central nervous system tumors.

Low-dose chlorine disinfection poses a greater potential risk of antibiotic resistance genes and their pathogenic hosts.

Application of viral vector technology for neural tracing enabled the visualization of neural pathways in a manner that had been impossible by classic techniques. The development of highly efficient retrograde vector played a pivotal role in its success. This chapter explains the strategy, protocol, and the expected results for visualization of selective neural pathways by double viral vector infection method. This method utilizes the combination of lentiviral vector showing retrograde gene transfer and adeno-associated viral (AAV) vector to split the TET-Off/TET-On system to these vectors. By co-injection of these vectors at the target and the origins of the pathway, it is possible to label a specific population of neurons that connect the two injection sites. The enhancement of transgene expression by TET system results in Golgi-like visualization of the cells from their dendrites to axon terminals. Using this technique, the corticothalamic cells are specifically labeled in their entirety including their collateral axons.

Exploring the molecular basis of serotyping and antibiotic resistance differences in Riemerella anatipestifer based on pan-genomics and machine learning.

Metformin drives the antibiotic resistome in activated sludge by reshaping microbial communities and promoting horizontal gene transfer.

Prevalence and molecular epidemiology of optrA-positive Enterococcus in herders and yaks from high-altitude Tibet, China.

Prevalence and dissemination of bacterial human pathogens in agricultural environments: A food safety and health concern.

Phytopathogenic bacteria are responsible for devastating agricultural losses globally. However, the chemical control of these pathogens is compromised by escalating resistance, environmental pollution, antibiotic resistance gene transfer, and a scarcity of validated antibacterial targets. To fill this gap, this review provides a critical and chemically-focused discussion of recent breakthroughs, aiming to bridge the gap between synthetic innovation, modern target discovery, and rational, data-driven design. Herein, we delineate emerging antibacterial compounds, emphasizing their structural diversity, structure-activity relationships, novel modes of action, and molecular targets. Furthermore, advanced methodologies for discovering and validating antibacterial targets are thoroughly examined, along with deep mechanistic insights. A forward-looking perspective on transformative approaches is also provided. This review aims to guide interdisciplinary efforts and stimulate the development of effective, sustainable, and environmentally friendly next-generation phytobactericides by offering the analysis urgently required by the field.

Nanoscale zero-valent iron coupled with microorganisms enhances the removal of organochlorine pesticides in groundwater: Insights from the role of cascading effects and horizontal gene transfer.