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Abstract The function of proteins depends on their correct structure and proper dynamics. Understanding the dynamics of target proteins facilitates drug design and development. However, dynamic information is often hidden in the spatial structure of proteins. It is important but difficult to identify the specific residues that play a decisive role in protein dynamics. Here, we report that a critical glycine residue (Gly463) dominates the motion of threonyl-tRNA synthetase (ThrRS) and the sensitivity of the enzyme to antibiotics. Obafluorin (OB), a natural antibiotic, is a novel covalent inhibitor of ThrRS. The binding of OB induces a large conformational change in ThrRS. Through five crystal structures, biochemical and biophysical analyses, and computational simulations, we found that Gly463 plays an important role in the dynamics of ThrRS. Mutating this flexible residue into more rigid residues did not damage the enzyme’s three-dimensional structure but significantly improved the thermal stability of the enzyme and suppressed its ability to change conformation. These mutations cause resistance of ThrRS to antibiotics that are conformationally selective, such as OB and borrelidin. This work not only elucidates the molecular mechanism of the self-resistance of OB-producing Pseudomonas fluorescens but also emphasizes the importance of backbone kinetics for aminoacyl-tRNA synthetase-targeting drug development.

Abstract Aminoacyl-tRNA synthetases (aaRSs) play a central role in the translation of genetic code, serving as attractive drug targets. Within this family, the lysyl-tRNA synthetase (LysRS) constitutes a promising antimalarial target. ASP3026, an anaplastic lymphoma kinase (ALK) inhibitor was recently identified as a novel Plasmodium falciparum LysRS (PfLysRS) inhibitor. Here, based on cocrystal structures and biochemical experiments, we developed a series of ASP3026 analogues to improve the selectivity and potency of LysRS inhibition. The leading compound 36 showed a dissociation constant of 15.9 nM with PfLysRS. The inhibitory efficacy on PfLysRS and parasites has been enhanced. Covalent attachment of l-lysine to compound 36 resulted in compound 36K3, which exhibited further increased inhibitory activity against PfLysRS but significantly decreased activity against ALK. However, its inhibitory activity against parasites did not improve, suggesting potential future optimization directions. This study presents a new example of derivatization of kinase inhibitors repurposed to inhibit aaRS.

Structures of E. coli threonyl-tRNA synthetase in complex with natural product obafluorin (OB) reveal that OB is a unique covalent inhibitor.

Abstract Introduction Oxidative stress and inflammatory responses are often the predominant detrimental factors associated with spinal cord injury (SCI). This study investigates the potential therapeutic effects of albiflorin (AF) on alleviating inflammation and oxidative stress in the rat model with SCI. Methods Initially, the behavior of SCI‐induced rats is examined by Basso−Beattie−Bresnahan score and the inclined plane examination. Then, the immunohistochemical staining of inflammasome‐related protein (for instance, NACHT, LRR, and PYD domains‐containing protein 3, NLRP3) is performed in combination with enzyme‐linked immunosorbent assay (ELISA) of corresponding proinflammatory factors to assess the immunomodulatory effects of AF. Further, the markers involved in oxidative stress are examined by ELISA and western blot analysis analyses. Results These findings indicated that AF could alleviate motor dysfunction and the loss of neuron cells in SCI‐induced rats. Mechanistically, AF could attenuate the inflammatory responses by reducing oxidative stress and activating nuclear erythroid‐related factor 2 (Nrf2)/heme oxygenase‐1 (HO‐1) pathway in SCI rats. Depleting the antioxidant capacity by inhibiting glutathione biosynthesis could counteract the anti‐inflammatory activity of AF in SCI rats. Conclusions Together, our data suggested that AF could serve as a potential therapeutic agent against the aggravation of SCI in rats.

Carbohydrates are fundamental molecules involved in nearly all aspects of lives, such as being involved in formating the genetic and energy materials, supporting the structure of organisms, constituting invasion and host defense systems, and forming antibiotics secondary metabolites. The naturally occurring carbohydrates and their derivatives have been extensively studied as therapeutic agents for the treatment of various diseases. During 2000 to 2021, totally 54 carbohydrate-based drugs which contain carbohydrate moities as the major structural units have been approved as drugs or diagnostic agents. Here we provide a comprehensive review on the chemical structures, activities, and clinical trial results of these carbohydrate-based drugs, which are categorized by their indications into antiviral drugs, antibacterial/antiparasitic drugs, anticancer drugs, antidiabetics drugs, cardiovascular drugs, nervous system drugs, and other agents.

The development of photocatalysts with a wide spectral response and effective carrier separation capability is essential for the green degradation of tetracycline hydrochloride. In this study, a magnetic recyclable Z-scheme ZnO/ZnFe2O4 heterojunction (ZZF) was successfully constructed via the solid phase method, using MIL-88A(Fe)@Zn as the precursor. An appropriate band gap width and Z-scheme charge transfer mechanism provide ZZF with excellent visible light absorption performance, efficient charge separation, and a strong redox ability. Under visible light irradiation, the degradation efficiency of tetracycline hydrochloride for the optimal sample can reach 86.3% within 75 min in deionized water and 92.9% within 60 min in tap water, exhibiting superior stability and reusability after five cycles. Moreover, the catalyst in the water can be conveniently recovered by magnetic force. After visible light irradiation for 70 min, the temperature of the reaction system increased by 21.9 °C. Its degradation constant (35.53 × 10−3 min−1) increased to 5.1 times that at room temperature (6.95 × 10−3 min−1). Using thermal energy enhances the kinetic driving force of the reactants and facilitates carrier migration, meaning that more charge is available for the production of •O2− and •OH. This study provides a potential candidate for the efficient degradation of tetracycline hydrochloride by combining thermal catalysis with a photocatalytic heterojunction.

Aminoacyl-tRNA synthetases (aaRSs) catalyze the ligation of amino acids to cognate tRNAs by consuming one molecule of ATP. Magnesium is essential for the enzymes’ activity. Certain class II aaRSs, such as lysyl-tRNA synthetase (LysRS) and seryl-tRNA synthetase (SerRS), recognize ATP together with three magnesium ions in the active site. The detailed role of how these magnesium ions facilitate the ATP recognition by the enzyme is unclear. Here, we report analyses of a crystal structure of human LysRS, in which the two enzymatic pockets of the LysRS dimer are in different states. One pocket is vacant of ATP, and the other is in an intermediate state of ATP recognition. Interestingly, only one magnesium ion instead of three is bound in both states. Compared with our previously solved LysRS structures, we proposed the order of binding for the three magnesium ions. These structures also reveal multiple intermediate ATP-bound states during the amino acid activation reaction, providing critical insights into the mechanisms of the magnesium-dependent enzyme activity of class II aaRSs.

SNAI family members are transcriptional repressors that induce epithelial-mesenchymal transition during biological development. SNAIs both have tumor-promoting and tumor-inhibiting effect. There are key regulatory effects on tumor onset and development, and patient prognosis in infiltrations of immune cell and tumor microenvironmental changes. However, the relationships between SNAIs and immune cell infiltration remain unclear. We comprehensively analyzed the roles of SNAIs in cancer. We used Oncomine and TCGA data to analyze pan-cancer SNAI transcript levels. By analyzing UALCAN data, we found correlations between SNAI transcript levels and breast cancer patient characteristics. Kaplan–Meier plotter analysis revealed that SNAI1 and SNAI2 have a bad prognosis, whereas SNAI3 is the opposite. Analysis using the cBio Cancer Genomics Portal revealed alterations in SNAIs in breast cancer subtypes. Gene Ontology analysis and gene set enrichment analysis were used to analyze differentially expressed genes related to SNAI proteins in breast cancer. We used TIMER to analyze the effects of SNAI transcript levels, mutations, methylation levels, and gene copy number in the infiltration of immune cell. Further, we found the relationships between immune cell infiltration, SNAI expression levels, and patient outcomes. To explore how SNAI proteins affect immune cell, we further studied the correlations between immunomodulator expression, chemokine expression, and SNAI expression. The results showed that SNAI protein levels were correlated with the expression of several immunomodulators and chemokines. Through analysis of PharmacoDB data, we identified antitumor drugs related to SNAI family members and analyzed their IC50 effects on various breast cancer cell lines. In summary, our study revealed that SNAI family members regulate different immune cells infiltrations by gene copy number, mutation, methylation, and expression level. SNAI3 and SNIA1/2 have opposite regulatory effects. They all play a key role in tumor development and immune cell infiltration, and can provide a potential target for drug therapy.

The current COVID‐19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), is an enormous threat to public health. The SARS‐CoV‐2 3C‐like protease (3CLpro), which is critical for viral replication and transcription, has been recognized as an ideal drug target. Herein, it is identified that three herbal compounds, Salvianolic acid A (SAA), (–)‐Epigallocatechin gallate (EGCG), and Oridonin, directly inhibit the activity of SARS‐CoV‐2 3CLpro. Further, blocking SARS‐CoV‐2 infectivity by Oridonin is confirmed in cell‐based experiments. By solving the crystal structure of 3CLpro in complex with Oridonin and comparing it to that of other ligands with 3CLpro, it is identified that Oridonin binds at the 3CLpro catalytic site by forming a CS covalent bond, which is confirmed by mass spectrometry and kinetic study, blocking substrate binding through a nonpeptidomimetic covalent binding mode. Thus, Oridonin is a novel candidate to develop a new antiviral treatment for COVID‐19.

This paper proposes a novel chaotic block image encryption algorithm based on deep convolutional generative adversarial networks (DCGANs), quaternions, an improved Feistel network, and an overall scrambling and diffusion mechanism. First, a new hyperchaotic system is introduced and combined with DCGANs to generate a random sequence with better randomness and complexity as a key stream. This sequence is then combined with a quaternion and an improved Feistel network encryption of a colour plaintext image by utilizing the key block matrix to ultimately achieve overall scrambling and diffusion of the cipher image. Finally, the security of this algorithm is quantitatively and qualitatively analysed. The simulation results show that the proposed hyperchaotic system has a large key space and good random characteristics and that the new algorithm yields adequate security and can resist brute-force attacks and chosen-plaintext attacks. Therefore, this approach provides a new way to achieve secure transmission and protection of image information.

In this study, silicone rubber (SiR) with 0, 90, and 180 parts of aluminum hydroxide (Al(OH)3, ATH) contents prepared in the laboratory was treated in a certain concentration of NO2 for 0, 12, 24, and 36 h. Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and thermogravimetry (TG) were used to study the changes in the surface structure and thermal stability of SiR, as well as the influence of Al(OH)3 on the properties of SiR. According to AFM, the root-mean-square roughness of ATH-90 SiR was 192 nm, which was 2.7 times of ATH-0 SiR. With the incorporation of ATH, the surface of SiR became more susceptible to corrosion by NO2. According to FT-IR and XPS, with the increase in aging time, the side chain Si-CH3 of polydimethylsiloxane (PDMS) was oxidized gradually and a few of nitroso -NO2 groups were formed. According to TG, the incorporation of ATH caused the maximum decomposition rate temperature of PDMS to advance from 458.65 °C to 449.37 and 449.26 °C, which shows that the thermal stability of SiR degraded by adding ATH. After NO2 aging, a new decomposition stage appeared between 75 and 220 °C (stage Ⅰ), and this decomposition trend was similar to aluminum nitrate, which was proven to reduce the thermal stability of PDMS. The effects of NO2 on the surface structure and thermal stability of different ATH contents of silicone rubber were preliminarily clarified by a variety of characterization methods, which provided ideas for the development of silicone rubber resistant to NO2 aging.

In this study, functional graphene oxide (f-GO) nanosheets were prepared to enhance the NO2 resistibility of room-temperature-vulcanized (RTV) silicone rubber. A nitrogen dioxide (NO2) accelerated aging experiment was designed to simulate the aging process of nitrogen oxide produced by corona discharge on a silicone rubber composite coating, and then electrochemical impedance spectroscopy (EIS) was used to test the process of conductive medium penetration into silicone rubber. After exposure to the same concentration (115 mg·L−1) of NO2 for 24 h, at an optimal filler content of 0.3 wt.%, the impedance modulus of the composite silicone rubber sample was 1.8 × 107 Ω·cm2, which is an order of magnitude higher than that of pure RTV. In addition, with an increase in filler content, the porosity of the coating decreases. When the content of the nanosheet increases to 0.3 wt.%; the porosity reaches a minimum value 0.97 × 10−4%, which is 1/4 of the porosity of the pure RTV coating, indicating that this composite silicone rubber sample has the best resistance to NO2 aging.

The second messenger Ap4A contributes to mast cell activation by interacting with HINT1 but the molecular mechanism is not fully understood. Here, the authors show that Ap4A regulates downstream signaling by polymerizing HINT1 and provide insights into how specificity over other second messengers is achieved.

Silicone rubber is widely used as an insulating material. In this article, silicone rubber samples were prepared by varying the content of crosslinker (2,5-bis(tert-butyl-peroxy)-2,5-dimethylhexane, DBPMH), and the free volume holes in the samples were investigated by means of positron annihilation lifetime spectroscopy (PALS) measurement. The surface chemical structure, surface micromorphology and water diffusion of the samples after corona discharge treatment were studied by FTIR, SEM and EIS measurements, respectively. As the crosslinker weight ratio increased from 0.2 wt.% to 1.5 wt.%, the mean free volume hole size first decreased and then remained unchanged. However, the concentration of free volume holes did not vary as the crosslinker weight ratio increased. SEM morphologies show that surface cracks were produced on samples having high crosslinking levels after corona treatment. The water diffusion coefficient of samples after corona treatment increased from 3.13 × 10−10 cm2 s−1 to 17.68 × 10−10 cm2 s−1 in the initial immersion period, as the crosslinker weight ratio increased from 0.2 wt.% to 3.0 wt.%. The results indicated that deterioration of samples with high crosslinking levels were more serious and water repellency more easily lost. The corona resistance ability of low crosslinking level silicone rubber stems from internal low molecular weight molecules.

The organic piezoelectric polymer polyvinylidene fluoride (PVDF) has attracted extensive research because of its excellent flexibility and mechanical energy-harvesting properties. Here, the electrospinning technique was taken to fabricate synthesized fiber membranes of a PVDF/cellulose acetate (CA) composite. The obtained PVDF/CA electrospun fiber membranes (EFMs) were employed to prepare a flexible nanogenerator. XRD and FTIR spectroscopy revealed the enhancement of piezoelectric behavior due to an increase in β-phase in PVDF/CA EFMs compared with cast films. The PVDF/CA fibers (mass ratio of PVDF to CA = 9:1) showed an output voltage of 7.5 V and a short-circuit current of 2.1 μA under mechanical stress of 2 N and frequency of 1 Hz, which were 2.5 and two times greater than those of the pure PVDF fibers, respectively. By charging a 4.7 µF capacitor for 15 min with the voltage generated by the PVDF/CA EFMs, nine LED lamps could be lit. The work provides an effective approach to enhancing the piezoelectric effects of PVDF for low-power electronic loading of macromolecule polymers.

Modifying materials by ions with multiple valence states is an effective way for enhancing their properties. NiFe layered double hydroxides (NiFe LDHs) were prepared by using a hydrothermal method. Efficient LDH photocatalyst was synthesized by the modification of NiFe LDHs with Fe(III). Electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller surface area, photoluminescence spectroscopy, and UV-Vis diffuse reflectance spectroscopy were used to investigate the morphology, crystal structure, and optical properties of the NiFe LDHs. The photocatalytic and adsorption performances were examined in the degradation of methyl orange. NiFe LDHs exhibited higher adsorption property but lower photocatalytic activity. After modification with Fe(III), the introducing of Fe ions and recrystallization of LDHs led to the distance decreasing between NiFe LDH sheets and exhibit higher photocatalytic performance.

Uniform polyaniline (PANI) nanotubes were synthesized by a self-assembly method under relatively dilute hydrochloric acid (HCl) solution. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and UV-Vis-NIR spectroscopy were employed to characterize the morphology and molecular structure of the PANI products. SEM images show that the PANI nanotubes have uniform morphology and form compact coating on the substrate surface. For comparison, aggregated PANI was also synthesized by conventional polymerization method. The performance of the PANI products on carbon steel was studied using eletrochemical measurement and immersion corrosion experiment in 3.5 wt% NaCl aqueous solution. The corrosion potentials of carbon steel samples increase by 0.196 V and 0.060 V after coated with PANI nanotubes and aggregated PANI, respectively, and the corrosion currents density decrease by about 76.32% and 36.64%, respectively. The 6-day immersion experiment showed that the carbon steel samples coated by PANI nanotubes showed more excellent anticorrosion performance, because the more compact coating formed by PANI nanotubes may inhibit the corrosion process between the anodic and cathodic.

To study the pile-forming mechanism and bearing deformation characteristics of continuous flight auger (CFA) piles, a series of procedures, including helical drilling, pulling up/grouting, and inserting cage/pile forming, were simulated in clay-sand double-layer foundations by a homemade model drilling machine system in laboratory model tests. The effects of two different pile-forming methods on the load transfer and bearing characteristics of the piles were investigated by performing a model test comparison of CFA piles and bored piles. The experimental results show that there exist a soil improvement effect around the pile and a diameter expansion effect during the drilling process and grouting process for the CFA pile, which can effectively improve the lateral friction resistance of the pile. Compared with the bored pile, the pile diameter in the middle of the CFA pile increased by 19%, and the total lateral friction resistance of the CFA pile increased by 9.1% at a high load (1500 N). The comparative results of the model tests show that the bearing capacity of a single CFA pile increased by 50.0% and that the total settlement decreased by 40.5%. The results of the in situ test piles show that the load-settlement curves of the two pile types are similar under low-medium loads and that the lateral friction resistance of the CFA pile under high loads is better developed, which is relatively consistent with the model test results.

Carbon fiber/ceramic composite demonstrates excellent electro-thermal performance that can be applied in various heating applications. However high temperature ceramization inevitably causes oxidation of carbon fiber and negatively influences its electro-thermal property. Herein, a graphene coated carbon fiber/ceramic composite via one-step firing with rapid and stable temperature responsiveness is proposed. Crystal structure, morphological feature, electrical property and electrothermal behavior of the modified carbon fibers and carbon fiber/ceramic composite were investigated. The results showed effectively protective effect of coating and sintering of carbon fiber under N2 environment, resulting in greatly improved electro-thermal and mechanical properties. The composite based on 24 k carbon fibers and 1 cm thickness ceramic sintering reached about 65 °C at 6 V in only 10 min and the cooling process lasted 30 min from 82 °C to room temperature, presenting highly responsive heating and good temperature storage performance. The tensile strength and elongation at break of the single graphene coated carbon fiber increased 12% and 200%. The great electro-thermal features and strong mechanical properties of the modified carbon fibers make the carbon fiber/ceramic composite a good candidate for in-door temperature control and out-door deicing applications.

The activation of TGF-β signaling has been implicated in cancer metastasis. Here, the authors show that OTUD1 suppresses metastasis by antagonizing the TGF-β pathway via the deubiquitination of SMAD7, and its loss correlates with poor prognosis in breast cancer.

In this paper, gas chromatography–mass spectrometry (GC–MS) and positron annihilation lifetime spectroscopy (PALS) were used to probe the changes of oligomers and the polydimethylsiloxane (PDMS) network in silicone rubber, after different durations of UVA/UVB irradiation. At the early stage (4-D9 decreases. The o-Ps intensity of the extracted silicone rubber increases in the stage after UVB irradiation. These results indicate the crosslinking of oligomers into the PDMS network. After a long duration (>300 h) of UVB irradiation, D4 was generated and the lifetime of τ3 also increased, indicating the rupture of the Si-O bond in the PDMS network. These two aging processes were termed the post curing process and the chain session process. The new finding was that UVA could only induce the post curing process; UVB causes the rupture of the chemical bond in silicone rubber. Photons of UVB could break the C-H bond, and then trigger the backbiting decomposition of PDMS, breaking the Si-O bond, while the photons of UVA cannot. The fact that D4 was generated after UVB irradiation can be used to evaluate the UVB stability of silicone rubber in the future.

Aminoacyl-tRNA synthetases (aaRSs) are enzymes that catalyze the transfer of amino acids to their cognate tRNAs as building blocks for translation. Each of the aaRS families plays a pivotal role in protein biosynthesis and is indispensable for cell growth and survival. In addition, aaRSs in higher species have evolved important non-translational functions. These translational and non-translational functions of aaRS are attractive for developing antibacterial, antifungal, and antiparasitic agents and for treating other human diseases. The interplay between amino acids, tRNA, ATP, EF-Tu and non-canonical binding partners, had shaped each family with distinct pattern of key sites for regulation, with characters varying among species across the path of evolution. These sporadic variations in the aaRSs offer great opportunity to target these essential enzymes for therapy. Up to this day, growing numbers of aaRS inhibitors have been discovered and developed. Here, we summarize the latest developments and structural studies of aaRS inhibitors, and classify them with distinct binding modes into five categories.

Vaccines against Porcine circovirus type 2 (PCV2) have been studied intensely and found to be effective in decreasing mortality and improving growth in swine populations. In this study, interleukin-23 (IL-23) gene was cloned from peripheral blood mononuclear cells (PBMCs) of Tibetan pigs and inserted into a eukaryotic VR1020 expression vector-VRIL23. Coated with chitosan (CS), the VRIL23-CS was intramuscularly injected into 3-week-old piglets with PCV2 vaccine. The blood was collected after vaccination at 0, 1, 2, 4, 8, and 12 weeks, respectively, to detect the immunological changes. The IgG2a and specific PCV2 antibodies were detected using ELISA, and blood CD4+ and CD8+ T cells were quantified by flow cytometry. Quantitative fluorescence PCR was used to evaluate the expression of immune genes. The results indicate that leukocytes, erythrocytes, and CD4+ and CD8+ T cells increased significantly in the blood of VRIL23-CS inoculated piglets in comparison with the control (p < 0.05) and so did the IgG2a and PCV2 antibodies. In addition, the expressions of Toll-like receptor (TLR) 2, TLR7, cluster of differentiation (CD) 45, IL-15, IL-12, signal transducer and activator of transcription (STAT)1, STAT2, STAT3, STAT4, and B-cell lymphoma (Bcl)-2 genes were also obviously higher in the VRIL23-CS inoculated pigs at different time points (p < 0.05). Overall, the results demonstrated that VRIL23-CS can enhance the comprehensive immune responses to PCV2 vaccine in vivo and has the promising potential to be developed into a safe and effective adjuvant to promote the immunity of pig against PCV disease.

Aminoacyl-tRNA synthetases-interacting multifunctional protein3 (AIMP3/p18) is involved in the macromolecular tRNA synthetase complex via its interaction with several aminoacyl-tRNA synthetases. Recent reports reveal a novel function of AIMP3 as a tumor suppressor by accelerating cellular senescence and causing defects in nuclear morphology. AIMP3 specifically mediates degradation of mature Lamin A (LmnA), a major component of the nuclear envelope matrix; however, the mechanism of how AIMP3 interacts with LmnA is unclear. Here we report solution-phase hydrogen/deuterium exchange (HDX) for AIMP3, LmnA, and AIMP3 in association with the LmnA C-terminus. Reversed-phase LC coupled with LTQ 14.5 T Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) results in high mass accuracy and resolving power for comparing the D-uptake profiles for AIMP3, LmnA, and their complex. The results show that the AIMP3-LmnA interaction involves one of the two putative binding sites and an adjacent novel interface on AIMP3. LmnA binds AIMP3 via its extreme C-terminus. Together these findings provide a structural insight for understanding the interaction between AIMP3 and LmnA in AIMP3 degradation.

Improving the electrocatalytic performance of oxygen evolution reaction (OER) is essential for oxygen-involved electrochemical devices, including water splitting and rechargeable metal−air batteries. In this work, we report that the OER performance of commercial catalysts of IrO2, Co3O4, and Pt-C can be improved by replacing the traditional Nafion® ionomer with newly synthesized copolymers consisting of protonated imidazolium moieties such as ion conductors and binders in electrodes. Specifically, such an improvement in OER performance for all the tested catalysts is more significant in basic and neutral environments than that under acidic conditions. We anticipate that the results will provide new ideas for the conceptual design of electrodes for oxygen-involved electrochemical devices.

Due to multiple charge transport pathways, adjustable layer spacing, compositional flexibility, low manufacturing cost, and absorption of visible light, layered double hydroxides (LDHs) are a promising material for wastewater treatment. In this study, LDH films and Fe-doped LDH films with different metal ions (Ni, Al, Fe) on the surface of conductive cloth were successfully prepared and applied for the photocatalytic degradation of wastewater containing methyl orange and Ag ions under visible-light irradiation. The chemical state of Fe ions and the composition of LDHs on methyl orange photodegradation were investigated. The experimental results showed that LDH films exhibited high photocatalytic activity. The photocatalytic activity of LDH films on methyl orange improved in the mixed wastewater, and the Fe-doped NiAl−LDH films exhibited best visible-light photocatalytic performance. The analysis showed that Ag ions in the mixed wastewater were reduced by the LDH films and subsequently deposited on the surface of the LDH films. The Ag nanoparticles acted as electron traps and promoted the photocatalytic activity of the LDH films on methyl orange. Thus, we have demonstrated that prepared LDH films can be used in the treatment of mixed wastewater and have broad application prospects in environmental remediation and purification processes.