Mitogenomics reveals extremely low genetic diversity in the endangered Jilin clawed salamander: Implications for its conservation.

The Jilin clawed salamander (Onychodactylus zhangyapingi) is an endemic, endangered, and level-two protected amphibian species of China. In the context of serious threats to amphibians worldwide, conservation studies of this endangered species are urgently needed. In this study, mitogenomic conservation genetics and species distribution modeling analyses were performed for O. zhangyapingi. Sixty-three samples were collected from nine different locations, and the complete mitochondrial genome was sequenced. Population genetic analyses revealed that O. zhangyapingi exhibits only one genetic structure with extremely low nucleotide diversity. Late Pleistocene climate cooling may have led to a reduction in effective population size and extremely low mitogenomic nucleotide diversity in this salamander, and the subsequent temperature increase (~20 kya to present) provided the opportunity for rapid population growth. The continuous highly suitable region for O. zhangyapingi is only approximately 3000 km2 on the southeastern boundary of Jilin Province, China. Fortunately, there are three large forested national nature reserves within the distribution of O. zhangyapingi that can effectively protect endangered species. Our findings suggest that O. zhangyapingi is a vulnerable species with a narrow distribution and extremely low genetic diversity, and we should pay more attention to the conservation management of this species.

A Promising Plant-Based Eugenol-Loaded Nano Delivery System (EUG@CMC-PGMA-CS) for Enhanced Antibacterial and Insect Repellent Behavior.

Pathogens and pests pose significant threats to global crop productivity and plant immunity, necessitating urgent measures from researchers to prevent pathogen contamination and pest damage to crops. A natural plant-based antibacterial agent, eugenol (EUG), has demonstrated excellent antimicrobial and insect repellent capabilities, but the characteristics of volatilization and poor dissolution limit the practical application. The nanoization of pesticide formulations holds promise in the development of highly effective pesticides for antibacterial and insecticidal purposes. Herein, a eugenol-loaded nano delivery system (EUG@CMC-PGMA-CS) was synthesized using glycidyl methacrylate (GMA) as a functional monomer to connect carrier core structure carboxymethyl cellulose (CMC) with shell structure chitosan (CS), and EUG was encapsulated within the carrier. EUG@CMC-PGMA-CS demonstrated excellent leaf affinity, with minimum contact angles (CAs) of 37.83 and 70.52° on hydrophilic and hydrophobic vegetable leaf surfaces, respectively. Moreover, the maximum liquid holding capacity (LHC) of EUG@CMC-PGMA-CS on both hydrophilic and hydrophobic vegetable leaf surfaces demonstrates a noteworthy 55.24% enhancement compared to the LHC of pure EUG. The in vitro release curve of EUG@CMC-PGMA-CS exhibited an initial burst followed by stable sustained release. It is with satisfaction that the nano delivery system demonstrated exceptional antibacterial properties against S. aureus and satisfactory insecticidal efficacy against Spodoptera litura. The development of this eugenol-loaded nano delivery system holds significant potential for enhanced antibacterial and insect repellents in agriculture, paving the way for the application of volatile bioactive substances.

Foliar application of glycine-functionalized nanopesticides for effective prevention and control of root-knot nematodes via a targeted delivery strategy.

BACKGROUND: Root-knot nematodes (RKNs) are the highly damaging pests for various crops, and the prevalence of RKNs has posed serious threats to worldwide agricultural harvest, severely affecting global food security and ecosystem health. Traditional pesticide systems on controlling RKNs generally cause environmental hazards and phytotoxicity due to the excessive use of pesticides resulted from low utilization efficiency. And effective approaches with biosafe and efficient features are highly demanded to break away from the dilemma caused by RKNs. RESULTS: In this research, a nanopesticide system with root-targeted delivery function was developed to achieve effective prevention and control of RKNs. The nanocarriers (MSN-KH560-Gly) and the obtained nanopesticides (EB@MSN-KH560-Gly) were proved to be biosafe. Also, this nanopesticide system demonstrated sustained release behavior. The grafting of glycine (Gly) significantly improved the pesticide contents translocating to cucumber roots (about 304.7%). Besides, such root-targeted delivery function resulted in no root nodule in cucumber plants after the foliar application of these nanopesticides (prevention rate of 100%). In addition, the root nodule numbers of the infected cucumber plants decreased by 71.67%. CONCLUSION: Foliar application of these Gly-functionalized nanopesticides achieved effective prevention and control of RKNs due to the root-targeted delivery property inherent in this nanopesticide system, and such root-targeted delivery strategy opens a novel and efficient method to protect crops from RKN invasion and thus facilitates the development of sustainable agriculture. © 2023 Society of Chemical Industry.

Strategy to enhance the semicontinuous anaerobic digestion of food waste via exogenous additives: experimental and machine learning approaches.

The anaerobic digestion (AD) of food waste (FW) was easy to acidify and accumulate ammonia nitrogen. Adding exogenous materials to the AD system can enhance its conversion efficiency by alleviating acidification and ammonia nitrogen inhibition. This work investigated the effects of the addition frequency and additive amount on the AD of FW with increasing organic loading rate (OLR). When the OLR was 3.0 g VS per L per day and the concentration of the additives was 0.5 g per L per day, the stable methane yield reached 263 ± 22 mL per g VS, which was higher than that of the group without the additives (189 mL per g VS). Methanosaetaceae was the dominant archaea, with a maximum abundance of 93.25%. Through machine learning analysis, it was found that the optimal daily methane yield could be achieved. When the OLR was within the range of 0-3.0 g VS per L per day, the pH was within the range of 7.6-8.0, and the additive concentration was more than 0.5 g per L per day. This study proposed a novel additive and determined its usage strategy for regulating the AD of FW through experimental and simulation approaches.

Preparation of Salicylic Acid-Functionalized Nanopesticides and Their Applications in Enhancing Salt Stress Resistance.

Soil salinization is one of the global ecological and environmental problems that are tremendously threatening to the sustainable development of agriculture and food supply. In this work, a facile strategy was proposed to enhance the salt stress resistance of plants by preparing salicylic acid (SA)-functionalized mesoporous silica nanocarriers loaded with emamectin benzoate (EB). The obtained nanopesticides demonstrated a particle size of less than 300 nm. As an endogenous plant hormone, the grafting of SA in this nanopesticide system improved the uptake and translocation of pesticides in cucumber plants by 145.06%, and the applications of such nanopesticides enhanced the salt stress resistance of plants. This phenomenon was accounted for by the SA-functionalized nanopesticides increasing the superoxide dismutase and peroxidase activities (640 and 175%, respectively) and reducing the malondialdehyde content (54.10%), correspondingly alleviating the accumulation of reactive oxygen species and cell damage in plants. The above results were also confirmed by Evans blue staining and NBT staining experiments on cucumber leaves. In addition, these nanopesticides exhibited high insecticidal toxicity, and they also demonstrated biosafety toward nontarget organisms due to their sustained release property. Therefore, this work developed a biosafe SA-functionalized nanopesticide system, and these newly developed nanopesticides have potential in the agricultural field for enhancing salt stress resistance of plants.

Exposing high-activity (111) facet CoO octahedral loading MXene quantum dots for efficient and stable photocatalytic H2 evolution.

Photocatalytic splitting of water for hydrogen generation is a green and renewable solution for converting solar energy to chemical energy; thus, the development of high-performance and stable photocatalytic materials has emerged as a research hotspot recently. Herein, a heterostructure composite photocatalyst of octahedral CoO uniformly modified with novel nitrogen-doped MXene quantum dots (N-MQDs) is successfully designed using a typical solvothermal approach. The optimum photocatalytic hydrogen evolution efficiency of the prepared N-MQDs@CoO heterojunction composite is 82.54 µmol g-1 h-1 with visible light, which is 16.57 times higher compared to the pure CoO. A series of photoelectrochemical tests were further performed to elucidate the photocatalytic hydrogen evolution mechanism. The remarkable improvement of activity is primarily attributed to the synergistic interaction between the closely spaced interface contacts and energy level matching among high conductivity Ti3C2 MXene quantum dots with CoO octahedra, dramatically hastening the segregation and transfer of photo-generated carriers. This study provides new ideas for the construction of MXene quantum dot-based co-photocatalysts with highly efficient photocatalytic performance and stability toward solar energy conversion applications.

Sulphate-reducing bacteria-mediated pyrite formation in the Dachang Tongkeng tin polymetallic deposit, Guangxi, China.

Mediation by sulphate-reducing bacteria (SRB) is responsible for pyrite (FeS2) formation. The origin of the Dachang tin polymetallic ore field is related to the mineralisation of submarine hydrothermal vent sediments. Here, we investigated SRB in these ores via morphological, chemical, and isotopic analyses. Polarised and scanning electron microscopy indicated that trace SRB fossils in the metal sulphide ore were present in the form of tubular, beaded, and coccoidal bodies comprising FeS2 and were enclosed within a pyrrhotite (FeS) matrix in the vicinity of micro-hydrothermal vents. The carbon (C), nitrogen (N), and oxygen (O) contents in the FeS2 synthesised by SRB were high, and a clear biological Raman signal was detected. No such signals were discerned in the peripheral FeS. This co-occurrence of FeS, FeS2, and the remains of bacteria (probably chemoautotrophic bacteria) was interpreted as the coprecipitation process of SRB-mediated FeS2 formation, which has, to the best of our knowledge, not been reported before. Our study also illustrates that combined energy-dispersive X-ray spectroscopy, Raman spectroscopy, and isotopic analysis can be used as a novel methodology to document microbial-mediated processes of mineral deposition in submarine hydrothermal vent ecology on geological time scales.

Comparison of thermal stability of Mo/Si multilayers with different crystallinities of Mo layers.

To investigate the thermal stability of Mo/Si multilayers with different initial crystallinities of Mo layers, two kinds of Mo/Si multilayers were deposited by DC magnetron sputtering and annealed at 300°C and 400°C. The period thickness compactions of multilayers with crystalized and quasi-amorphous Mo layers were 0.15 nm and 0.30 nm at 300°C, respectively, and the stronger the crystallinity, the lower the extreme ultraviolet reflectivity loss. At 400°C, the period thickness compactions of multilayers with crystalized and quasi-amorphous Mo layers were 1.25 nm and 1.04 nm, respectively. It was shown that multilayers with a crystalized Mo layer had better thermal stability at 300°C but were less stable at 400°C than multilayers with a quasi-amorphous Mo layer. These changes in stability at 300°C and 400°C were due to the significant transition of the crystalline structure. The transition of the crystal structure leads to increased surface roughness, more interdiffusion, and compound formation.

[CiteSpace knowledge map of research hotspots and frontiers of Polygalae Radix].

In this study, the Web of Science and China National Knowledge Infrastructure(CNKI) were searched comprehensively for the literature about the research on Polygalae Radix. After manual screening, 1 207 Chinese articles and 263 English articles were included in this study. Excel was used to draw the line chart of the annual number of relevant publications. CiteSpace 6.1.R3 was used for the visual analysis of author cooperation, publishing institutions, keyword co-occurrence, keyword clustering, and bursts in the research on Polygalae Radix. The results showed that the number of articles published in Chinese and English increased linearly, which indicated the rising research popularity of Polygalae Radix. WANG J and LIU X were the authors publishing the most articles in Chinese and English, respectively. Shanxi University of Chinese Medicine and Chinese Academy of Medical Sciences were the research institutions with the largest number of Chinese and English publications in this field, respectively. The institutions publishing the relevant articles in English formed a system with the Chinese Academy of Medical Sciences as the core. According to the keywords, the research hotspots of Polygalae Radix included variety selection and breeding, quality standard, extraction and identification of active chemical components, prescription compatibility, processing, clinical medication rules, and pharmacological mechanism. The research frontiers were the molecular mechanisms of Polygalae Radix and its active components in exerting the protective effect on brain nerve, regulating receptor pathways, alleviating anxiety and Alzheimer's disease, as well as data mining and clinical medication summary. This study has reference significance for the topic selection and frontier identification of the future research on Polygalae Radix.

Li-N2 Battery for Ammonia Synthesis and Computational Insight.

Electrochemical synthesis of ammonia is deemed as an alternative to the fossil-fuel-driven Haber-Bosch (HB) process, in which Li-mediated nitrogen reduction (LiNR) is the most promising scheme. Continuous lithium-mediated nitrogen reduction for ammonia synthesis (C-LiNR) has recently been reported in high-level journals with many foggy internal reactions. Synthesizing ammonia in a separate way may be profitable for understanding the mechanism of LiNR. Herein, an intermittent lithium-mediated nitrogen reduction for ammonia synthesis (I-LiNR) was proposed, three steps required for I-LiNR were achieved in the cathode chamber of a Li-N2 battery. Discharge, stand, and charge in the Li-N2 battery correspond to N2 lithification, protonation, and lithium regeneration, respectively. It can also realize the quasi-continuous process with practical significance because it could be carried out through identical batteries. Products such as Li3N, LiOH, and NH3 are detected experimentally, which demonstrate a definite reaction pathway. The mechanism of the Li-N2 battery, the Li-mediated synthesis of ammonia, and LiOH decomposition are explored through density functional theory calculations. The role of Li in dinitrogen activation is highlighted. It expands the range of LiOH-based Li-air batteries and may guide the study from Li-air to Li-N2; attention has been given to the reaction mechanism of Li-mediated nitrogen reduction. The challenges and opportunities of the procedure are discussed in the end.

Design of an Efficient CNN-based Cough Detection System on Lightweight FPGA.

Precisely and automatically detecting the cough sound is of vital clinical importance. Nevertheless, due to privacy protection considerations, transmitting the raw audio data to the cloud is not permitted, and therefore there is a great demand for an efficient, accurate, and low-cost solution at the edge device. To address this challenge, we propose a semi-custom software-hardware co-design methodology to help build the cough detection system. Specifically, we first design a scalable and compact convolutional neural network (CNN) structure that generates many network instances. Second, we develop a dedicated hardware accelerator to perform the inference computation efficiently, and then we find the optimal network instance by applying network design space exploration. Finally, we compile the optimal network and let it run on the hardware accelerator. The experimental results demonstrate that our model achieves 88.8% classification accuracy, 91.2% sensitivity, 86.5% specificity, and 86.5% precision, while the computation complexity is only 1.09M multiply-accumulation (MAC). Additionally, when implemented on a lightweight field programmable gate array (FPGA), the complete cough detection system only occupies 7.9K lookup tables (LUTs), 12.9K flip-flops (FFs), and 41 digital signal processing (DSP) slices, providing 8.3 GOP/s actual inference throughput and total power dissipation of 0.93 W. This framework meets the needs of partial application and can be easily extended or integrated into other healthcare applications.

Comparative Study on Microstructure of Mo/Si Multilayers Deposited on Large Curved Mirror with and without the Shadow Mask.

The Mo/Si multilayer mirror has been widely used in EUV astronomy, lithography, microscopy and other fields because of its high reflectivity at the wavelength around 13.5 nm. During the fabrication of Mo/Si multilayers on large, curved mirrors, shadow mask was a common method to precisely control the period thickness distribution. To investigate the effect of shadow mask on the microstructure of Mo/Si multilayers, we deposited a set of Mo/Si multilayers with and without the shadow mask on a curved substrate with aperture of 200 mm by direct current (DC) magnetron sputtering in this work. Grazing incidence X-ray reflectivity (GIXR), diffuse scattering, atomic force microscope (AFM) and X-ray diffraction (XRD) were used to characterize the multilayer structure and the EUV reflectivity were measured at the National Synchrotron Radiation Laboratory (NSRL) in China. By comparing the results, we found that the layer microstructure including interface width, surface roughness, layer crystallization and the reflectivity were barely affected by the mask and a high accuracy of the layer thickness gradient can be achieved.

Salicylic acid functionalized zein for improving plant stress resistance and as a nanopesticide carrier with enhanced anti-photolysis ability.

BACKGROUND: There is a serious global problem of salinization of arable land, causing large reduction in world food production. Use of plant hormones is an effective way to reduce damage caused to crops and salt stress. RESULTS: In this study, PEI-EDA was modified with AM-zein and grafted with plant hormone SA (AM-zein-SA) and used as a nano-pesticide carrier to load emamectin benzoate (EB). The use of AM-zein-SA as a nano-pesticide carrier could reduce the damage caused by salt stress to crops. The structure of AM-zein-SA was characterized by FTIR, UV, fluorescence, Raman, and 1H NMR spectroscopic techniques. AM-zein-SA could effectively improve the resistance of EB to ultraviolet radiations, resistance of cucumber to salt stress, and the absorption of EB by plants. The experimental results showed that AM-zein-SA could effectively improve the anti-UV property of EB by 0.88 fold. When treated with 120 mmol NaCl, the germination rate of cucumber seeds under salt stress increased by 0.93 fold in presence of 6.25 mg/L carrier concentration. The POD and SOD activities increased by 0.50 and 1.21 fold, whereas the content of MDA decreased by 0.23 fold. In conclusion, AM-zein-SA nano-pesticide carrier could be used to improve the salt resistance of crops and the adhesion of pesticides to leaves. CONCLUSION: AM-zein-SA, without undergoing any changes in its insecticidal activity, could simultaneously improve the salt stress resistance and salt stress germination rate of cucumber, reduce growth inhibition due to stress under high-concentration salt, and had a good effect on crops. In addition, EB@AM-zein-SA obviously improved the upward transmission rate of EB, as compared with EB. In this study, SA was grafted onto zein-based nano-pesticide carrier, which provided a green strategy to control plant diseases, insects, and pests while reducing salt stress on crops in saline-alkali soil.

A polymer sponge with dual absorption of mechanical and electromagnetic energy.

Polyaniline, a modified conductive polymer, has been widely studied in the field of electromagnetic (EM) wave absorption due to its excellent dielectric and conductive properties. However, it has limited applications due to its hard molding and processing, and poor mechanical stability. In this study, ice crystals with rapid directional growth were used as templates for polymerization to obtain polymer precursors with directional channels, and then ternary polymer sponges with oriented pore channels were designed and synthesized using a secondary template method. The Poisson's ratio of the study material reaches -1.52 and it absorbs 5.1 mJ/cm3 energy in a single compression cycle at 25% longitudinal strain. Also, the material has more than 90% absorption efficiency for X-band EM waves at a thickness of 4 mm. The flexibility of polymer molecular chains and the arrangement of oriented pores are the reasons for the negative Poisson's ratio property of the material, while the key to the loss of EM energy in the absorption process is the conversion of quinone bipolaron to monopolaron structure. Due to its large-scale green preparation with ice crystal as the template, this lightweight and robust material system are ideal for absorbing EM waves under extreme conditions.

CMC based microcapsules for smart delivery of pesticides with reduced risks to the environment.

Inefficient use of traditional pesticides causes serious environmental pollution. Stimuli-responsive pesticide formulations improve the utilization efficiency of target pests and reduce harm to non-target organisms and the environment. Herein, multi-stimuli-responsive avermectin (AVM) polyurea microcapsules (AVM@CM-SS-PU) are prepared by interfacial polymerization with modified carboxymethyl cellulose CMC-SS-NH2 as the wall material and hexadecane as the temperature-responsive core. The microcapsules are 3.90 µm in size and the encapsulation efficiency of AVM is 88.23 %. The photostability of AVM@CM-SS-PU is 5-times that of AVM solution. The insecticidal effect of AVM solution and AVM emulsifiable concentrate (EC) decreases to 13.3 % and 16.6 %, respectively, after UV irradiation for 180 min, whereas that of AVM@CM-SS-PU still remains at 50.0 %. AVM@CM-SS-PU has better foliar affinity and releases under the stimuli of temperature, glutathione, pH, cellulase, and urease. Hence, it has high insecticidal activity and biosafety. This smart controlled-release pesticide formulation provides a promising solution for green agriculture.

Risk factors for venous thromboembolism in patients with spinal cord injury: A systematic review and meta-analysis.

CONTEXT: Patients with spinal cord injury (SCI) are at high risk for venous thromboembolism (VTE). The risk factors for VTE in patients with SCI are complex. OBJECTIVE: This meta-analysis was conducted to clarify the risk factors for VTE in patients with SCI. METHODS: The Cochrane Library, PubMed, EBSCO, Web of Science, China National Knowledge Infrastructure (CNKI), China Biomedical Literature Database (CBM), Wanfang Med Data Database, and VIP Database were searched to identify studies reporting on risk factors for VTE in patients with SCI. RESULTS: The meta-analysis included 25 studies. Findings showed that risk of VTE in patients with SCI was significantly associated with middle- and old-age (OR = 2.08, 95%CI, 1.47, 2.95), male sex (OR = 1.41, 95%CI, 1.26, 1.59), complete paralysis (OR = 3.69, 95%CI, 2.60, 5.24), personal/family history of venous thrombosis (OR = 1.95, 95%CI, 1.35, 2.81), history of smoking (OR = 2.67, 95%CI, 1.79, 3.98), lack of compression therapy (OR = 2.44, 95%CI, 1.59, 3.73), presence of lower limb/pelvic fracture (OR = 3.47, 95%CI, 1.79, 6.75), paraplegia (OR = 1.81, 95%CI, 1.49, 2.19), and diabetes (OR = 4.24, 95%CI, 2.75, 6.52). CONCLUSION: The meta-analysis identified 9 risk factors for VTE in patients with SCI. Healthcare providers should be aware of the risk factors for VTE when rehabilitating patients with SCI.

Research progress on vaccines against human respiratory syncytial virus / 中国生物制品学杂志

@#Human respiratory syncytial virus(hRSV)is one of the main pathogens that cause lower respiratory tract infection in infants and the elderly.hRSV genome contains 10 genes with a full length of 15 222 bp,encoding 11 proteins(9structural proteins and 2 non-structural proteins).Different proteins play different roles in the pathogenesis of hRSV.With the in-depth research on the biological and structural characteristics of hRSV,various types of hRSV vaccines have been developed,making rapid progress.For example,hRSV attenuated live vaccine hRSV ?NS2/?1313/I1314L has entered Phase II clinical trial,and hRSV subunit protein vaccine Pre-F-GCN4t has entered Phase III clinical trial.In this paper,the biological characteristics of hRSV and the types of hRSV vaccines with rapid progress are reviewed so as to provide a reference for the development of hRSV vaccines in China.

A MALDI-TOF mass spectrometry-based method for detection of copy number variations in BRCA1 and BRCA2 genes.

Background: Identifying germline mutations in BRCA1 and BRCA2 genes (BRCAs) would benefit the carriers in multiple aspects. In addition to single-nucleotide variations and small indels, copy number variations (CNVs) is also an indispensable component of identifiable mutations in BRCAs. A sensitive, rapid and throughput-flexible method to detect CNVs would be preferred to meet the rising clinical requirements for BRCAs testing. Methods: We developed a MALDI-TOF-MS-based method (MS assay) which included three steps: first, multiplex end-point PCR followed by a single base extension reaction; second, automated analyte transfer and data acquisition; third, data analysis. We applied MS assay to detect CNVs in BRCAs in 293 Chinese patients with ovarian or pancreatic cancer. All the samples were examined by targeted next-generation sequencing (TS) simultaneously. Samples were further cross-validated by multiplex ligation-dependent probe amplification (MLPA) if the results from MS assay and TS were inconsistent. Long range PCR was then applied to identify the exact breakpoints in BRCAs. Results: MS assay introduced highly multiplexed panels to detect CNVs of BRCAs semi-quantitatively. Simplified on-board data analysis was available for MS assay and no complex bioinformatics was needed. The turnaround time of MS assay was less than 8 hours with a hands-on time of only 40 min. Compared to TS, MS assay exhibited higher sensitivity (100% vs. 75%) and was more flexible in throughput, with the reagent cost per sample remaining constant no matter how many samples were examined per assay. A total of eight CNVs in BRCAs were detected from the 293 samples, and the molecular breakpoints were successfully identified in five samples through long-range PCR followed by Sanger sequencing. Conclusion: Our results suggested that MS assay might be an effective method in primary screening for CNVs in genes such as BRCAs, especially when short turnaround time and/or high sensitivity is a top priority.

A bibliometric study of global trends in diabetes and gut flora research from 2011 to 2021.

Background and objectives: Diabetes mellitus is a serious metabolic disease that causes a serious economic burden worldwide. Gut flora is a major component of diabetes research, and the aim of this study was to understand the trends and major components of research related to diabetes and gut flora in the last 11 years. Methods: We searched the Web of Science Core Collection database for articles on diabetes and gut flora related research from 2011-2021 on July 2, 2022. The literature data were analyzed for country, institution, author, steward, journal, and highly cited literature using Citespace.5.8.R3 and Vosviewer1.6.17. Results: Finally 4834 articles that met the requirements were included. The overall trend of articles published in the last 11 years is increasing, and the trend of articles published after 2019 is increasing significantly. In total, 109 countries, 4820 institutions, and 23365 authors were involved in the field of research. The highest number of publications was 1262 articles from the United States, the institution with the most publications was the University of Copenhagen with 134 articles, and the author with the most publications was PATRICE D CANI with 52 articles. Conclusion: The number of studies related to diabetes and intestinal flora is increasing and more and more researchers are involved in this field. Intestinal flora provides a key research direction for the treatment of diabetes. In the future, gut flora will remain the focus of the diabetes field.

C-Diazeniumdiolate Graminine in the Siderophore Gramibactin Is Photoreactive and Originates from Arginine.

Siderophores are synthesized by microbes to facilitate iron acquisition required for growth. Catecholate, hydroxamate, and α-hydroxycarboxylate groups comprise well-established ligands coordinating Fe(III) in siderophores. Recently, a C-type diazeniumdiolate ligand in the newly identified amino acid graminine (Gra) was found in the siderophore gramibactin (Gbt) produced by Paraburkholderia graminis DSM 17151. The N-N bond in the diazeniumdiolate is a distinguishing feature of Gra, yet the origin and reactivity of this C-type diazeniumdiolate group has remained elusive until now. Here, we identify l-arginine as the direct precursor to l-Gra through the isotopic labeling of l-Arg, l-ornithine, and l-citrulline. Furthermore, these isotopic labeling studies establish that the N-N bond in Gra must be formed between the Nδ and Nω of the guanidinium group in l-Arg. We also show the diazeniumdiolate groups in apo-Gbt are photoreactive, with loss of nitric oxide (NO) and H+ from each d-Gra yielding E/Z oxime isomers in the photoproduct. With the loss of Gbt's ability to chelate Fe(III) upon exposure to UV light, our results hint at this siderophore playing a larger ecological role. Not only are NO and oximes important in plant biology for communication and defense, but so too are NO-releasing compounds and oximes attractive in medicinal applications.