RESUMO
BACKGROUND: Amino acids are not only the main form of N in rice, but also are vital for its growth and development. These processes are facilitated by amino acid transporters within the plant. Despite their significance, only a few AAP amino acid transporters have been reported. RESULTS: In this study, we observed that there were differences in the expression of amino acid transporter OsAAP7 among 521 wild cultivated rice varieties, and it directly negatively correlated with tillering and grain yield per plant. We revealed that OsAAP7 protein was localized to the endoplasmic reticulum and had absorption and transport affinity for amino acids such as phenylalanine (Phe), lysine (Lys), leucine (Leu), and arginine (Arg) using subcellular localization, yeast substrate testing, fluorescent amino acid uptake, and amino acid content determination. Further hydroponic studies showed that exogenous application of amino acids Phe, Lys and Arg inhibited the growth of axillary buds in the overexpression lines, and promoted the elongation of axillary buds in the mutant lines. Finally, RNA-seq analysis showed that the expression patterns of genes related to nitrogen, auxin and cytokinin pathways were changed in axillary buds of OsAAP7 transgenic plants. CONCLUSIONS: This study revealed the gene function of OsAAP7, and found that blocking of amino acid transporter OsAAP7 with CRISPR/Cas9 technology promoted tillering and yield by determining basic and neutral amino acids accumulation in rice.
Assuntos
Oryza , Proteínas de Plantas , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Plantas Geneticamente Modificadas , Aminoácidos Neutros/metabolismo , Regulação da Expressão Gênica de Plantas , Aminoácidos/metabolismoRESUMO
Perovskite solar cells (PSCs) have grabbed much attention of researchers owing to their quick rise in power conversion efficiency (PCE). However, long-term stability remains a hurdle in commercialization, partly due to the inclusion of necessary hygroscopic dopants in hole transporting materials, enhancing the complexity and total cost. Generally, the efforts in designing dopant-free hole transporting materials (HTMs) are devoted toward small molecule and polymeric HTMs, where small molecule based HTMs (SM-HTMs) are dominant due to their reproducibility, facile synthesis, and low cost. Still, the state-of-art dopant-free SM-HTM has not been achieved yet, mainly because of the knowledge gap between device engineering and molecular designs. From a molecular engineering perspective, this article reviews dopant-free SM-HTMs for PSCs, outlining analyses of chemical structures with promising properties toward achieving effective, low-cost, and scalable materials for devices with higher stability. Finally, an outlook of dopant-free SM-HTMs toward commercial application and insight into the development of long-term stability PSCs devices is provided.
RESUMO
Overall photocatalytic conversion of CO2 and pure H2 O driven by solar irradiation into methanol provides a sustainable approach for extraterrestrial synthesis. However, few photocatalysts exhibit efficient production of CH3 OH. Here, BiOBr nanosheets supporting atomic Cu catalysts for CO2 reduction are reported. The investigation of charge dynamics demonstrates a strong built-in electric field established by isolated Cu sites as electron traps to facilitate charge transfer and stabilize charge carriers. As result, the catalysts exhibit a substantially high catalytic performance with methanol productivity of 627.66 µmol gcatal -1 h-1 and selectivity of ≈90% with an apparent quantum efficiency of 12.23%. Mechanism studies reveal that the high selectivity of methanol can be ascribed to energy-favorable hydrogenation of *CO intermediate giving rise to *CHO. The unfavorable adsorption on Cu1 @BiOBr prevents methanol from being oxidized by photogenerated holes. This work highlights the great potential of single-atom photocatalysts in chemical transformation and energy storage reactions.
RESUMO
Helium-neon (He-Ne) laser mutagenesis is widely used in microbiology and plant breeding. In this study, two frameshift mutant representative strains of Salmonella typhimurium TA97a and TA98 and two base pair substitution types TA100 and TA102 were employed as model microorganisms to assess DNA mutagenicity induced by He-Ne laser (3 J·cm-2·s-1, 632.8 nm) for 10, 20, and 30 min. The results revealed that the optimal laser application was 6 h in the mid-logarithmic growth stage. Low-power He-Ne laser for short treatment inhibited cell growth, and continued treatment stimulated the metabolism. The effects of the laser on TA98 and TA100 were the most prominent. Sequencing results from 1500 TA98 revertants showed that there were 88 insertion and deletion (InDel) types in the hisD3052 gene, of which the InDels unique to laser were 21 more than that of the control. Sequencing results from 760 TA100 revertants indicated that laser treatment created Pro (CCC) in the product of the hisG46 gene more likely to be replaced by His (CAC) or Ser (TCC) than by Leu (CTC). Two unique non-classical base substitutions, CCC â TAC and CCC â CAA, also appeared in the laser group. These findings will provide a theoretical basis for further exploration of laser mutagenesis breeding. KEY POINTS: ⢠Salmonella typhimurium served as model organism for laser mutagenesis study. ⢠Laser promoted the occurrence of InDels in the hisD3052 gene of TA98. ⢠Laser promoted the occurrence of base substitution in the hisG46 gene of TA100.
Assuntos
Mutagênicos , Salmonella typhimurium , Mutagênicos/toxicidade , Salmonella typhimurium/genética , Mutagênese , DNA , Lasers , Testes de Mutagenicidade/métodosRESUMO
Multimetallic nanoclusters (MMNCs) offer unique and tailorable surface chemistries that hold great potential for numerous catalytic applications. The efficient exploration of this vast chemical space necessitates an accelerated discovery pipeline that supersedes traditional "trial-and-error" experimentation while guaranteeing uniform microstructures despite compositional complexity. Herein, we report the high-throughput synthesis of an extensive series of ultrafine and homogeneous alloy MMNCs, achieved by 1) a flexible compositional design by formulation in the precursor solution phase and 2) the ultrafast synthesis of alloy MMNCs using thermal shock heating (i.e., â¼1,650 K, â¼500 ms). This approach is remarkably facile and easily accessible compared to conventional vapor-phase deposition, and the particle size and structural uniformity enable comparative studies across compositionally different MMNCs. Rapid electrochemical screening is demonstrated by using a scanning droplet cell, enabling us to discover two promising electrocatalysts, which we subsequently validated using a rotating disk setup. This demonstrated high-throughput material discovery pipeline presents a paradigm for facile and accelerated exploration of MMNCs for a broad range of applications.
RESUMO
Three frequently encountered problems-a variety of fault types, data with insufficient labels, and missing fault types-are the common challenges in the early fault diagnosis of space flywheel rotor systems. Focusing on the above issues, this paper proposes an intelligent early fault diagnosis method based on the multi-channel convolutional neural network with hierarchical branch and similarity clustering (HB-SC-MCCNN). First, a similarity clustering (SC) method is integrated into the parameter-shared dual MCCNN architecture to set up as the basic structural block. The hierarchical branch model and additional loss are then added to SC-MCCNN to form a hierarchical branch network, which simplifies the problem of fault multi-classification into binary classification with multi-steps. Based on the self-learning characteristics of the proposed model, the unlabeled data and the missing fault types in the training set are re-labeled to realize the re-training of the network. The results of the experiments for comparing the abilities between the proposed method and several advanced deep learning models confirm that on the established early fault dataset of the space flywheel rotor system, the proposed method successfully achieves the hierarchical diagnosis and presents stronger competitiveness in the case of insufficient labeled data and missing fault types at the same time.
RESUMO
The pursuit of high metal utilization in heterogeneous catalysis has triggered the burgeoning interest of various atomically dispersed catalysts. Our aim in this review is to assess key recent findings in the synthesis, characterization, structure-property relationship and computational studies of dual-atom catalysts (DACs), which cover the full spectrum of applications in thermocatalysis, electrocatalysis and photocatalysis. In particular, combination of qualitative and quantitative characterization with cooperation with DFT insights, synergies and superiorities of DACs compare to counterparts, high-throughput catalyst exploration and screening with machine-learning algorithms are highlighted. Undoubtably, it would be wise to expect more fascinating developments in the field of DACs as tunable catalysts.
RESUMO
Catalysts made of in situ exsolved metal nanoparticles often demonstrate promising activity and high stability in many applications. However, the traditional approach is limited by perovskites as prevailing precursor and requires high temperature typically above 900 K. Here, with the guidance of theoretical calculation, an unprecedented and substantially facile technique is demonstrated for Cu nanoparticles exsolved from interstitially Cu cations doped nickel-based hydroxide, which is accomplished swiftly at room temperature and results in metal nanoparticles with a quasi-uniform size of 4 nm, delivering an exceptional CO faradaic efficiency of 95.6% for the electrochemical reduction of CO2 with a notable durability. This design principle is further proven to be generally applicable to other metals and foregrounded for guiding the development of advanced catalytic materials.
RESUMO
Electrocatalysts with single metal atoms as active sites have received increasing attention owing to their high atomic utilization efficiency and exotic catalytic activity and selectivity. This review aims to provide a comprehensive summary on the recent development of such single-atom electrocatalysts (SAECs) for various energy-conversion reactions. The discussion starts with an introduction of the different types of SAECs, followed by an overview of the synthetic methodologies to control the atomic dispersion of metal sites and atomically resolved characterization using state-of-the-art microscopic and spectroscopic techniques. In recognition of the extensive applications of SAECs, the electrocatalytic studies are dissected in terms of various important electrochemical reactions, including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), carbon dioxide reduction reaction (CO2RR), and nitrogen reduction reaction (NRR). Examples of SAECs are deliberated in each case in terms of their catalytic performance, structure-property relationships, and catalytic enhancement mechanisms. A perspective is provided at the end of each section about remaining challenges and opportunities for the development of SAECs for the targeted reaction.
RESUMO
This work was to study the regulatory mechanism of large intergenic non-coding RNA 0196 (LINC0196), miR-584-5p, miR-34a-5p, and tripartite motif 59 (TRIM59) on neuroblastoma. The interaction among the four was analyzed to provide a research basis for the clinical treatment of neuroblastoma at the molecular level. The human neuroblastoma SK-N-SH cells were collected and cultured. According to the transfection methods, the cells were divided into control group (without any treatment), si-LINC0196 group (si-LINC0196 transfection), si-LINC0196-NC group (si-LINC0196 vector transfection), miR-584-5p group (miR-584-5p mimic transfection), miR-584-5p-NC group (miR-584-5p inhibitor transfection), miR-34a-5p group (miR-34a-5p mimic transfection), and miR-34a-5p-NC group (miR-34a-5p inhibitor transfection). The proliferation, migration, and apoptosis of SK-N-SH cells in each group were compared. The effects of LINC0196, miR-584-5p, miR-34a-5p, and TRIM59 were evaluated. The expressions of LINC0196 and TRIM59 in SK-N-SH cells in si-LINC0196, miR-584-5p, and miR-34a-5p groups were up-regulated. miR-584-5p and miR-34a-5p in si-LINC0196-NC, miR-584-5p-NC, and miR-34a-5p-NC groups decreased significantly (P < 0.05). The proliferation rate, migration rate, and invasiveness of SK-N-SH cells in miR-584-5p and miR-34a-5p groups were lower than those in si-LINC0196-NC, miR-584-5p-NC, and miR-34a-5p-NC groups, while the apoptosis rate increased (P < 0.05). After miR-584-5p and miR-34a-5p transfections, the relative activities of WT-LINC0196 and WT-TRIM59 dual luciferase were greatly inhibited (P < 0.05). LINC0196 could regulate TRIM59 by regulating miR-584-5p and miR-34a-5p, thereby indirectly regulating cell proliferation, apoptosis, migration, and invasion of SK-N-SH cells.
Assuntos
MicroRNAs , Neuroblastoma , RNA Longo não Codificante , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Criança , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Luciferases , MicroRNAs/genética , MicroRNAs/metabolismo , Neuroblastoma/genética , RNA Longo não Codificante/genética , Proteínas com Motivo TripartidoRESUMO
Metal-organic frameworks (MOFs) derived metal oxides/porous carbon nanocomposites were used as adsorbents to remove pollutants from wastewater. The adsorption performance of the metal oxides/porous carbon nanocomposites could be improved by introducing functional groups. In this study, hydroxyl-modified zirconia/porous carbon nanocomposite (C-UiO-66-OH) was prepared and tested, choosing carbamazepine as a typical pollutant. The results showed that the adsorption capacity (186.21 mg g-1) of C-UiO-66-OH was 6.96 times to that of normal UiO-66. The Langmuir isotherm model and pseudo-first-order kinetic model was well fit the adsorption process. The thermodynamic parameters indicated that the adsorption process was spontaneous and endothermic. The adsorbent regeneration could be accomplished by washing C-UiO-66-OH with ethanol and DI water. The good adsorption/desorption performance comes from the synergistic effect of (EDA) interaction and hydrogen bond between C-UiO-66-OH and CBZ molecule. A membrane prepared by immobilizing C-UiO-66-OH into melamine foam (MF) with sodium alginate (SA) was also investigated for CBZ adsorption. The results indicated the excellent removal efficiency (86.0%) and good regeneration of the prepared membrane. Therefore, this paper provides an efficient and applicable way to remove CBZ from water.
Assuntos
Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Adsorção , Carbamazepina , Carbono , Radical Hidroxila , Cinética , Estruturas Metalorgânicas , Nanocompostos/química , Ácidos Ftálicos , Porosidade , Água/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , ZircônioRESUMO
University of Oslo-66 (UiO-66) was a potential adsorbent for removing various pollutants from wastewater. Modifying the UiO-66 surface with different functional groups could enhance the adsorption performance. In this study, the UiO-66 modified with a functional group of -NH2 or -NO2 was prepared and tested to adsorb different pollutants. The results showed that -NO2 modified UiO-66 increased the adsorption capacity of tetracycline by 17 times to 94.08 mg g-1 compared with unmodified UiO-66. The adsorption process of UiO-66-NO2 followed the pseudo-second-order adsorption kinetic model and Langmuir isotherm model with a maximum isotherm adsorption capacity of 127.32 mg g-1. The adsorption interaction was hydrogen bonding and electrostatic attraction. The UiO-66-NO2 also showed good adsorption performance to Co2+, Methylene blue, Congo red. Fixing UiO-66-NO2 into hydrogel performed a stable absorption performance with a high absorption capacity (71.56 mg g-1) to TC and a good regeneration rate (85%) after five cycles, providing a novel applicable way to remove pollutants from wastewater.
Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Hidrogéis , Cinética , Estruturas Metalorgânicas , Dióxido de Nitrogênio , Ácidos Ftálicos , Águas Residuárias , Poluentes Químicos da Água/análise , Purificação da Água/métodosRESUMO
BACKGROUND: Removal of self-expanding esophageal metal stents that have been implanted for a long time can be difficult and risky. PURPOSE: In this paper, we describe the use of the "inversion technique" under fluoroscopy for removal of self-expandable nitinol esophageal stents that have been placed for long periods and evaluate the effectiveness and safety of the method. METHODS: Retrospective analysis of patients who underwent removal of self-expanding nitinol esophageal stents by the inversion technique under fluoroscopy at our center. Demographic characteristics, type of esophageal stents, stent retention time, reasons for stent removal, and related complications were collected from the case records and analyzed. RESULTS: A total of 112 metal esophageal stents (62 fully covered esophageal stents and 50 partially covered esophageal stents) were extracted from the 107 patients included in the study. Indications for stent implantation were malignant esophageal stenosis (27 patients), benign esophageal stenosis (42 patients), and esophageal fistula (38 patients). Median duration of stent retention was 77 days (29-727 days). All stents were removed successfully without major complications such as esophageal rupture, massive hemorrhage, asphyxia, or cardiorespiratory arrest. CONCLUSION: Inversion technique under fluoroscopy appears to be a safe, effective, and quick procedure for removal of self-expanding nitinol esophageal stent after long-term placement.
Assuntos
Estenose Esofágica , Ligas , Remoção de Dispositivo/métodos , Estenose Esofágica/etiologia , Fluoroscopia , Humanos , Metais , Estudos Retrospectivos , Stents/efeitos adversos , Resultado do TratamentoRESUMO
BACKGROUND: Tracheal stent implantation is widely used in clinic settings. Timely removal of tracheal stents could prevent or reduce related complications. This study was aimed at evaluating the feasibility and safety of removing tracheal stents by an interventional technique under fluoroscopy. METHODS: Clinical data of patients with self-expanding uncovered tracheal stents removed by an interventional technique under fluoroscopy were analyzed retrospectively, including medical records, imaging findings, surgical records, and follow-up results. According to the type and time of stent placement and the proliferation of granulation tissue under bronchoscopy, different tracheal stent removal techniques were used to remove the tracheal stent under fluoroscopy, and the feasibility and safety of the interventions were analyzed. RESULTS: In all, 148 tracheal stents were removed from 112 patients; 95.9% (142/148) of the stents were completely removed and 4.1% (6/148) had a small amount of metal residue, and foreign-body forceps were removed under fiber bronchoscopy guidance. In 78 (69.6%), 32 (21.6%), and 6 (5.4%) patients, the tracheal stent was removed by the internal stripping, direct removal, and stent-in-stent methods, respectively. The overall stent removal time ranged from 11 to 111 (28.9 ± 20.1) min. During stent removal, 16 (14.3%) and 13 (11.6%) patients developed mild and moderate complications, respectively. There were no serious complications such as massive hemorrhage, mediastinal fistula, or death. CONCLUSIONS: An interventional technique under fluoroscopy for stent removal is a feasible, safe, and effective method and could serve as a technique for tracheal stent removal in clinical settings.
Assuntos
Stents , Traqueia , Remoção de Dispositivo/métodos , Fluoroscopia , Humanos , Estudos Retrospectivos , Stents/efeitos adversos , Traqueia/cirurgiaRESUMO
For millimeter-wave (MMW) imaging security systems, the image resolution promisingly determines the performance of suspicious target detection and recognition. Conventional synthetic aperture radar (SAR) imaging algorithms only provide limited resolution in active MMW imaging, which is limited by the system. In terms of enhancing the resolution of a region of interest (ROI) image containing suspicious targets, super-resolution (SR) imaging is adopted via Bayesian compressive sensing (BCS) implemented by fast Fourier transform (FFT). The spatial sparsity of MMW ROI images is well exploited with BCS to achieve resolution enhancement without computational cost. Both simulated and measured experiments confirm that the proposed scheme effectively improves the resolution of ROI images.
RESUMO
Defects and energy offsets at the bulk and heterojunction interfaces of perovskite are detrimental to the efficiency and stability of perovskite solar cells (PSCs). Herein, we designed an amphiphilic π-conjugated ionic compound (QAPyBF4 ), implementing simultaneous defects passivation and interface energy level alignments. The p-type conjugated cations passivated the surface trap states and optimized energy alignment at the perovskite/hole transport layer. The highly electronegative [BF4 ]- enriched at the SnO2 interface featured desired band alignment due to the dipole moment of this interlayer. The planar n-i-p PSC had an efficiency of 23.1 % with Voc of 1.2â V. Notably, the synergy effect elevated the intrinsic endothermic decomposition temperature of the perovskite. The modified devices showed excellent long-term thermal (85 °C) and operational stability at the maximum power point for 1000â h at 45 °C under continuous one-sun illumination with no appreciable efficiency loss.
RESUMO
Dielectric metasurfaces, which are capable of manipulating incident light, have been a novel branch of flat optics. This modulation ability is realized by nanostructures with space-variant geometrical parameters such as height and diameter. Therefore, accurate profile measurement of metasurfaces is of great importance. White-light scanning interferometry is widely used for profile measurement. The step height is retrieved by locating the envelope's peak. However, spurious fringes attached to the desired fringes were observed at the measured area near the edge of nanostructures. Their amplitude distributions vary with the density of nanostructures as well as distance to the edge. Further, anomalous coherence signals with two fringe envelopes are produced, which result in inaccurate measurement results. We attributed this phenomenon to the complex light modulation by the nanostructures. When referring to the anomalous coherence signals for the top of the nanostructures, one envelope is produced by the top, and the other is produced by the bottom; however, it is difficult to distinguish these two, which is the same case for the bottom of the nanostructures. To automatically solve these obstacles, a signal processing method, which integrates the image segmentation technology to identify and divide the anomalous coherence signals, along with a Morlet wavelet transform to extract the fringe envelope, suitable for any measured area of the dielectric metasurface, is proposed. One metasurface belt consisting of seven kinds of nanopillars with varying arrayed densities that produce different coherence signals is measured. The diameter distribution ranges from 500 to 1250 nm with a constant height of 1850 nm. The local periods in the X and Y directions are 3020 and 1740 nm, respectively. Measurement results demonstrate the validity of the proposed method for spurious fringes processing.
RESUMO
Marine phycosphere hosts cross-kingdom algae-bacteria interactions playing a variety of crucial roles in aquatic ecosystems especially for the prevention and control of harmful algal blooms (HABs). During the investigation of structural composition of phycosphere microbiota (PM) of diverse marine HAB dinoflagellates, a Gram-negative, strictly aerobic, non-motile and rod-shaped bacterium designated LZ-17T was isolated from the phycosphere of highly toxic Alexandrium catenella LZT09. The 16S rRNA gene sequence analysis and the multilocus sequence analysis (MLSA) based on five protein-coding housekeeping genes (atpD, gyrB, mutL, topA and rpoD) indicated that strain LZ-17T was affiliated to the genus Maritimibacter within the family Rhodobacteraceae, and closely related to Maritimibacter alkaliphilus HTCC2654T (99.1%), 'Maritimibacter harenae' DP07T (97.9%) and M. lacisalsi X12M-4T (95.7%). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain LZ-17T and the type strain of M. alkaliphilus were 96.9% and 74.7%. However, strain LZ-17T could be clearly distinguished from its closest by the phenotypical and phenotypical characteristics. Strain LZ-17T contained Q-10 as its major isoprenoid quinone, and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c), C16:0 and C16:0 2-OH as the predominant fatty acids (>10%). The major polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylcholine. The DNA G + C content was 64.3 mol%. Based on the polyphasic taxonomic characterization, strain LZ-17T represents a novel species of the genus Maritimibacter, for which the name Maritimibacter alexandrii sp. nov. is proposed, with the type strain LZ-17T (=CCTCC 2019005T = KCTC 72193T).
Assuntos
Dinoflagellida , Microbiota , Rhodobacteraceae , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
A new versatile actinobacterium designated as strain NJES-13 was isolated from the feces of the Antarctic emperor penguin. This new isolate was found to produce two active gephyromycin analogues and bioflocculanting exopolysaccharides (EPS) metabolites. Phylogenetic analysis based on pairwise comparison of 16S rRNA gene sequences showed that strain NJES-13 was closely related to Mobilicoccus pelagius Aji5-31T with a gene similarity of 95.9%, which was lower than the threshold value (98.65%) for novel species delineation. Additional phylogenomic calculations of the average nucleotide identity (ANI, 75.9-79.1%), average amino acid identity (AAI, 52.4-66.9%) and digital DNA-DNA hybridization (dDDH, 18.6-21.9%), along with the constructed phylogenomic tree based on the up-to-date bacterial core gene (UBCG) set from the bacterial genomes, unequivocally separated strain NJES-13 from its close relatives within the family Dermatophilaceae. Hence, it clearly indicated that strain NJES-13 represented a putative new actinobacterial species isolated from the gut microbiota of mammals inhabiting the Antarctic. The obtained complete genome of strain NJES-13 consisted of a circular 3.45 Mb chromosome with a DNA G+C content of 67.0 mol%. Furthering genome mining of strain NJES-13 showed the presence of five biosynthetic gene clusters (BGCs) including one type III PKS responsible for the biosynthesis of the core of gephyromycins, and a series of genes encoding for bacterial EPS biosynthesis. Thus, based on the combined phylogenetic and active metabolites characterization presented in this study, we confidently conclude that strain NJES-13 is a novel, fresh actinobacterial candidate to produce active gephyromycins and microbial bioflocculanting EPS, with potential pharmaceutical, environmental and biotechnological implications.
Assuntos
Actinobacteria/genética , Antraquinonas/metabolismo , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Spheniscidae , Animais , Regiões Antárticas , Organismos Aquáticos , Técnicas de Tipagem Bacteriana , Fezes/microbiologia , Humanos , Filogenia , Fitoterapia , RNA Ribossômico 16S/genéticaRESUMO
Desymmetrization of gem-dimethyl groups en route to the rhodium(III)-catalyzed enantioselective sp3 C-H amidation is reported. Synthetically important ß-amino alcohol derivatives were accessed in moderate to good yields and high enantioselectivity. The high enantioselectivity is enabled by an appropriate oxime directing group, sterically biased gem-groups in the C-H substrate, and high reactivity of the amidating reagent.