Cyclo[2]pyridine[8]pyrrole: An Expanded Porphyrinoid with Three Closed-Shell Oxidation States.

We report here an expanded porphyrinoid, cyclo[2]pyridine[8]pyrrole, 1, that can exist at three closed-shell oxidation levels. Macrocycle 1 was synthesized via the oxidative coupling of two open chain precursors and fully characterized by means of NMR and UV-vis spectroscopies, MS, and X-ray crystallography. Reduction of the fully oxidized form (1, blue) with NaBH4 produced either the half-oxidized (2, teal) or fully reduced forms (3, pale yellow), depending on the amount of reducing agent used and the presence or absence of air. Reduced products 2 or 3 can be oxidized to 1 by various oxidants (quinones, FeCl3, and AgPF6). Macrocycle 1 also undergoes proton-coupled reductions with I-, Br-, Cl-, SO32-, or S2O32- in the presence of an acid. Certain thiol-containing compounds likewise reduce 1 to 2 or 3. This conversion is accompanied by a readily discernible color change, making cyclo[2]pyridine[8]pyrrole 1 able to differentiate biothiols, such as cysteine (Cys), homocysteine (Hcy), and glutathione (GSH).

Genomic analyses provide insights into the polyploidization-driven herbicide adaptation in Leptochloa weeds.

Polyploidy confers a selective advantage under stress conditions; however, whether polyploidization mediates enhanced herbicide adaptation remains largely unknown. Tetraploid Leptochloa chinensis is a notorious weed in the rice ecosystem, causing severe yield loss in rice. In China, L. chinensis has only one sister species, the diploid L. panicea, whose damage is rarely reported. To gain insights into the effects of polyploidization on herbicide adaptation, we first assembled a high-quality genome of L. panicea and identified genome structure variations with L. chinensis. Moreover, we identified herbicide-resistance genes specifically expanded in L. chinensis, which may confer a greater herbicide adaptability in L. chinensis. Analysis of gene retention and loss showed that five herbicide target-site genes and several herbicide nontarget-site resistance gene families were retained during polyploidization. Notably, we identified three pairs of polyploidization-retained genes including LcABCC8, LcCYP76C1 and LcCYP76C4 that may enhance herbicide resistance. More importantly, we found that both copies of LcCYP76C4 were under herbicide selection during the spread of L. chinensis in China. Furthermore, we identified another gene potentially involved in herbicide resistance, LcCYP709B2, which is also retained during polyploidization and under selection. This study provides insights into the genomic basis of the enhanced herbicide adaptability of Leptochloa weeds during polyploidization and provides guidance for the precise and efficient control of polyploidy weeds.

Combined effects of S-metolachlor and benoxacor on embryo development in zebrafish (Danio rerio).

It is necessary to study the combined toxicity of an herbicide and its safener because the two are often used in combination. S-metolachlor and its safener benoxacor have been detected in aquatic environments and can individually damage the oxidative stress system in zebrafish embryos (Danio rerio). However, only their separate toxicity in zebrafish (Danio rerio) embryo development has been reported. This study assessed the combined toxicity of benoxacor and S-metolachlor in zebrafish embryo development, including acute toxicity, developmental toxicity, oxidative damage, and cell apoptosis. The 96-h LC50 values were higher in mixtures of benoxacor and S-metolachlor than in benoxacor alone. The treatments included S-metolachlor, Mix-1 (0.1 mg/L benoxacor + 0.1 mg/L S-metolachlor), Mix-2 (0.1 mg/L benoxacor + 0.3 mg/L S-metolachlor) and benoxacor alone. Embryos exposed to Mix-1 and Mix-2 had lower developmental toxicities, superoxide dismutase (SOD) activity, osx and cat expression levels than those exposed to benoxacor alone. Moreover, glutathione S-transferase (GST), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) activities, and the expressions of tbx16, nrf2, bcl2, and caspase9 were higher in the mixtures than in the benoxacor group. High-throughput RNA sequencing revealed that benoxacor had a greater effect on gene regulation than Mix-1 and Mix-2. The malformation rate, different enrichment gene numbers, and gene expression levels of hatched embryos were higher in Mix-1 than in Mix-2. The results indicate that a mixture of S-metolachlor and benoxacor has antagonistic effects in the early stage of embryo development. The mixtures can break the reactive oxygen species balance, causing abnormal cell apoptosis and developmental malformation in embryos. Besides investigating the combined toxicity of benoxacor and S-metolachlor in zebrafish embryo development, this study provides a risk assessment basis for a herbicide combined with its safener.

Macroevolutionary patterns in seed component mass and different evolutionary trajectories across seed desiccation responses.

Seed coat and seed reserve show substantial mass variation, play different roles in plant life strategies and are shaped by different selective forces. However, remarkably little is known about the macroevolution of the relative allocation in seed components and its influence on important ecophysiological processes. Using phylogenetic comparative methods and evolutionary modelling approaches, we modelled mass changes in seed components along individual lineages for 940 species and compared the patterns across seed desiccation responses. Seed component allocation was driven primarily by changes in reserve mass rather than coat mass, as evolutionary rates in reserve mass significantly outpaced those in coat mass. Although the scaling patterns between reserve mass and coat mass were similar across desiccation responses, desiccation-sensitive seeds allocated more and evolved faster in reserve compared to desiccation-tolerant seeds. The findings emphasize the relative importance of reserve to coat in the evolution of plant reproductive strategies, revealing potential ecological advantages gained by enlarged reserve. As the first quantification of the evolutionary tempo and mode of seed component mass, our study allows a detailed interpretation of evolutionary pathways underlying seed storage behaviours and advances the understanding of the evolution of desiccation sensitivity in seeds.

An allometry between seed kernel and seed coat shows greater investment in physical defense in small seeds.

PREMISE OF THE STUDY: Numerous studies have treated the mass of a whole seed as an integrated unit, although the components seed kernel and seed coat play different roles and are subject to different evolutionary selection pressures. In this study, we provided the first global-scale quantification of the relative biomass investments in seed coats and seed kernels. We tested the following hypotheses: there is a negative allometry between seed kernel mass and seed coat mass, and therefore, seed coat ratio (SCR) is negatively correlated with seed mass. METHODS: We compiled a global-scale data set from the published literature, including 680 plant species from 420 genera and 108 families. The relationships between seed components were quantified using standardized major axis regression, ordinary least squares regression, and phylogenetic independent analyses. KEY RESULTS: We found a weak but significantly negative allometry between seed kernel mass and seed coat mass, which resulted in a negative relationship between seed mass and SCR. Similar results were found after accounting for the phylogeny. CONCLUSIONS: The finding that smaller seeds invest more in protective tissues but less in stored reserves may explain the general prediction that larger seeds suffer greater predation than smaller seeds. Furthermore, this weak allometry may also explain, at least in part, why so many studies failed to identify a clear pattern of the effect of seed mass on many ecological processes. Our study suggests that the allometry between the two seed components must be considered when evaluating the ecological significance and evolutionary history of seed mass.

rs35301225 polymorphism in miR-34a promotes development of human colon cancer by deregulation of 3'UTR in E2F1 in Chinese population.

BACKGROUND: Previous reports have revealed that down-regulation of miR-34a expression can promote colorectal cancer (CRC) cell growth by targeting cell cycle-related transcriptional factor E2F1. To date, the function of the single nucleotide polymorphism (SNP) located in the mature region of miR-34a has not been investigated. METHODS: We performed a case-control study including 685 CRC patients and 618 cancer-free controls. Genotyping, real-time PCR assay, cell transfection, and the dual luciferase reporter assay were used in our study. Cell proliferation and cell cycle analysis were measured in CRC cells including Hct-116 and SW480. The overall survival of different genotypes was also investigated. RESULTS: We found that the rs35301225 polymorphism in miR-34a was involved in the occurrence of CRC by acting as a tumor suppressor by down-regulation of tumor-promoting gene E2F1. C/A SNP of miR-34a could promote CRC cell proliferation by up-regulation of E2F1. Also, C/A genotype can change the cell cycle by increasing the S phase percentage. Moreover, the SNP in rs35301225 of miR-34a was associated with tumor size and tumor differentiation, as well as metastasis in CRC patients; C/A SNP was related to the significantly enhanced expression of E2F1 and shorter survival in post-surgery CRC patients. CONCLUSIONS: rs35301225 in miR-34a was highly associated with a decreased risk of CRC in a Chinese population and might serve as a novel biomarker for colon cancer.

The Functional Variant in the 3'UTR of IGF1 with the Risk of Gastric Cancer in a Chinese Population.

BACKGROUND/AIMS: IGF-1 can act as an endocrine hormone and its signaling server as essential roles in regulating tumorigenesis. Polymorphisms in IGF-1 have been reported associated bad prognosis of with human cancer, but their association with the risk of human gastric cancer (GC) has not been found so far. In this study rs6218 located in the 3'UTR of IGF-1 was selected to evaluate its relationship with the risk of GC among Chinese population. METHODS: Questionnaire, SNaPshot genotype assay, real time PCR assay, cell transfection and the dual luciferase reporter assay were used in our study. RESULTS: SNP rs6218 in IGF-1 3'-UTR was involved in the occurrence of GC by acting as a tumor promotion factor while rs6128 acting as a risk factor. SNP rs6128 was also could be regulated by miR-603 which caused an up-regulation of IGF-1 in patients with UC and CC genotype. Furthermore, the carriers of UC and CC genotype presented a big tumor size as well as the high probability of metastasis. CONCLUSION: In conclusion, our findings have shown that the SNP rs6218 in IGF-1 3'-UTR, through disrupting the regulatory role of miR-603 in IGF-1 expression, rs16128 in IGF-1 might act as a promotion factor in the pathogenesis of GC.

Toxoplasma gondii nucleus coding apicoplast protein ACP synthesis and trafficking in delayed death.

This study aimed to explore Toxoplasma gondii nucleus coding apicoplast protein acyl carrier protein (ACP) synthesis and trafficking in delayed death. The recombinant T. gondii ACP was expressed by prokaryotic expression method, and anti-ACP polyclonal antibody was obtained from rabbit immune. T. gondii "delayed death" was induced by clindamycin (CLDM), and ACP transcription was determined by real-time PCR assay. The expression of ACP with transit type (t-ACP) and mature type (m-ACP) was determined by Western blotting with anti-ACP polyclonal antibody. The mutant-expressed ACP fused with green fluorescent protein (GFP) tag was constructed by pHX-ACP-GFP. The distribution of ACP in "delayed death" was observed by ACP-GFP fusion protein with a confocal microscope. T. gondii ACP transcription and t-ACP expression had no significant decrease in the early 4 h of "delayed death," but there has been a significant decrease in 6 h. The expression of m-ACP had a significant decrease in 4 h which occurred earlier than the t-ACP expression. The number of brightly dot green fluorescence in ACP-GFP mutant decreased with prolonged time. There was very little brightly dot green fluorescence in ACP-GFP mutant when treated with CLDM for 6 h. CLDM could suppress apicoplast proliferation and induce T. gondii "delayed death"; however, it could not directly suppress nucleus coding ACP transcription and expression. T. gondii lacking of apicoplast had a barrier of transit peptide cleavage and t-ACP could not be transformed into m-ACP. The reason for the decrease in ACP expression could be due to excessive t-ACP synthesis in tachyzoites resulting in a negative feedback for the ACP coding gene transcription.

[Overexpression of Toxoplasam gondii ROP18 by Tet-on Lentivirus Expression System].

OBJECTIVE: To construct a 293T mutant cell line over-expressing ROP18 of Toxoplasma gondii by Tet-on lentivirus expression system. METHODS: Rop18 gene of T. gondii was amplified by PCR, and inserted into a lentiviral vector pLVCT-tTR-KRAB. The recombinant plasmid pLVCT-tTR-KRAB-ROP18 (6 µg) and 293T human embryonic kidney cells were co-transfected with psPAX2 (4 µg) and pMD2.G (2 µg) for the packaging. The result of co-transfection was evaluated by fluorescence microscopy. At 48 h and 72 h after co-transfection, the supernatant of the packaging lentivirus was collected for the 293T cell infection. The doxycycline (DOX) was added into the medium to induce the ROP18 expression in 293T cells. The ROP18 fusion expression was observed under fluorescence microscope and detected by RT-PCR after induction. RESULTS: PCR product of the gene fragment encoding ROP18 was 960 bp. The recombinant plasmid pLVCT-tTR-KRAB-ROP18 was identified by PCR and restriction enzyme digestion. Green fluorescence was observed in 293T cells at 48 h post-transfection. Bright green fluorescence was observed in 293T cells at 24 h after DOX induction. RT-PCR results showed that a 960 bp specific band (ROP18 gene) was detectable in 293T cells. CONCLUSION: 293T cell line stably expressing ROP18 is established with Tet-on lentivirus expression system.

Rh(III) -catalyzed hydroacylation reactions between N-sulfonyl 2-aminobenzaldehydes and olefins.

Metal-catalyzed hydroacylation of olefins represents an important atom-economic synthetic process in CH activation. For the first time highly efficient Rh(III) Cp*-catalyzed hydroacylation was realized in the coupling of N-sulfonyl 2-aminobenzaldehydes with both conjugated and aliphatic olefins, leading to the synthesis of various aryl ketones. Occasionally, oxidative coupling occurred when a silver(I) oxidant was used.

[Construction of beta-hydroxyacyl-acyl carrier protein dehydratase mutant of Toxoplasma gondii by tetracycline inducible expression system].

OBJECTIVE: To construct a beta-hydroxyacyl-acyl carrier protein dehydratase (FABZ) mutant of Toxoplasma gondii with tetracycline inducible expression system. METHODS: The fabz gene was amplified from T. gondii genomic DNA, and then used to construct the tetracycline inducible expression vector pTetO7-Sag1-FABZ-Ty-DHFR. The vector was transfected into TATi strain by electroporation. The FABZ defective mutant was selected by pyrimethamine and limitting dilution assay. The expression of Ty-tagged mutant was detected by Western blotting. 5 x 10(5) tachyzoites of FABZ defective mutant were cultured in HFF in the presence of anhydrotetracycline (ATc, 1 microg/ml) for 24 h and 48 h, respectively. The expression of Ty-tagged FABZ protein in the mutant was detected by Western blotting. RESULTS: The mutant could express the transit peptide (t-FABZ) and mature FABZ (m-FABZ) with the Ty-epitope tag. After ATc added in culture medium for 24 h and 48 h, the expression of t-FABZ in the mutant decreased significantly (P<0.05). CONCLUSION: The FABZ mutant is constructed with a tetracycline inducible expression system.

The Pro-197-Thr mutation in the ALS gene confers novel resistance patterns to ALS-inhibiting herbicides in Bromus japonicus in China.

Introduction: Bromus japonicus is one of the most notorious agricultural weeds in China. The long-term use of ALS-inhibiting herbicides has led to rapid evolution of herbicide resistance in B. japonicus. B. japonicus population (BJ-R) surviving mesosulfuron-methyl treatment was collected from wheatland. Here, we aimed to confirm the resistance mechanisms in this putative resistant population. Methods: The dose-reponse tests were used to test the resistance level of the B. japonicus to ALS-inhibiting herbicides. Pretreatment with P450 and GST inhibitors and GST activity assays were used to determine whether P450 or GST was involved in the resistance of the BJ-R population. Sanger sequencing was used to analyse the ALS mutation of the BJ-R population. RT-qPCR was used to confirm the the expression levels of the ALS gene in mesosulfuron-methyl -resistant (BJ-R) and-susceptible (BJ-S) B. japonicus. An in vitro ALS activity assay was used to determine the ALS activity of the BJ-R and BJ-S populations. Homology modelling and docking were used to determine the binding energy of the BJ-R and BJ-S populations with ALS-inhibiting herbicides. Results: B. japonicus population (BJ-R) was confirmed to be 454- and 2.7-fold resistant to the SU herbicides mesosulfuron-methyl and nicosulfuron, and 7.3-, 2.3-, 1.1- and 10.8-fold resistant to the IMI herbicide imazamox, the TP herbicide penoxsulam, the PTB herbicide pyribenzoxim and the SCT herbicide flucarbazone-sodium, respectively, compared with its susceptible counterpart (BJ-S). Neither a P450 inhibitor nor a GST inhibitor could reverse the level of resistance to mesosulfuron-methyl in BJ-R. In addition, no significant differences in GST activity were found between the BJ-R and BJ-S. ALS gene sequencing revealed a Pro-197-Thr mutation in BJ-R, and the gene expression had no significant differences between the BJ-R and BJ-S. The ALS activity of BJ-R was 106-fold more tolerant to mesosulfuron-methyl than that of BJ-S. Molecular docking showed that the binding energy of the ALS active site and mesosulfuron-methyl was changed from -6.67 to -4.57 kcal mol-1 due to the mutation at position 197. Discussion: These results suggested that the Pro-197-Thr mutation was the main reason for the high resistance level of BJ-R to mesosulfuron-methyl. Unlike previous reports of the cross-resistance pattern conferred by this mutation, we firstly documented that the Pro-197-Thr mutation confers broad cross-resistance spectrums to ALS-inhibiting herbicides in B. japonicus.

Proteomic Analysis Comparison on the Ecological Adaptability of Quinclorac-Resistant Echinochloa crus-galli.

Barnyardgrass (Echinochloa crus-galli L.) is the most serious weed threatening rice production, and its effects are aggravated by resistance to the quinclorac herbicide in the Chinese rice fields. This study conducted a comparative proteomic characterization of the quinclorac-treated and non-treated resistant and susceptible E. crus-galli using isobaric tags for relative and absolute quantification (iTRAQ). The results indicated that the quinclorac-resistant E. crus-galli had weaker photosynthesis and a weaker capacity to mitigate abiotic stress, which suggested its lower environmental adaptability. Quinclorac treatment significantly increased the number and expression of the photosynthesis-related proteins in the resistant E. crus-galli and elevated its photosynthetic parameters, indicating a higher photosynthetic rate compared to those of the susceptible E. crus-galli. The improved adaptability of the resistant E. crus-galli to quinclorac stress could be attributed to the observed up-regulated expression of eight herbicide resistance-related proteins and the down-regulation of two proteins associated with abscisic acid biosynthesis. In addition, high photosynthetic parameters and low glutathione thiotransferase (GST) activity were observed in the quinclorac-resistant E. crus-galli compared with the susceptible biotype, which was consistent with the proteomic sequencing results. Overall, this study demonstrated that the resistant E. crus-galli enhanced its adaptability to quinclorac by improving the photosynthetic efficiency and GST activity.

Myeloid-derived suppressor cells: Are they involved in gestational diabetes mellitus?

Gestational diabetes mellitus (GDM) is currently the most common metabolic complication during pregnancy, with an increasing prevalence worldwide. Maternal immune dysregulation might be partly responsible for the pathophysiology of GDM. Myeloid derived suppressor cells (MDSCs) are a heterogeneous population of cells, emerging as a new immune regulator with potent immunosuppressive capacity. Although the fate and function of these cells were primarily described in pathological conditions such as cancer and infection, accumulating evidences have spotlighted their beneficial roles in homeostasis and physiological conditions. Recently, several studies have explored the roles of MDSCs in the diabetic microenvironment. However, the fate and function of these cells in GDM are still unknown. The current review summarized the existing knowledges about MDSCs and their potential roles in diabetes during pregnancy in an attempt to highlight our current understanding of GDM-related immune dysregulation and identify areas where further study is required.

Quinoxaline-fused octaphyrin(2.0.0.0.2.0.0.0). A rudimentary chemosensor.

A quinoxaline-fused octaphyrin(2.0.0.0.2.0.0.0) was synthesized by the FeCl3-induced oxidative coupling of an α-free quinoxaline-fused tetrapyrrole. This macrocycle adopts a figure-of-eight conformation in the solid state and acts as a rudimentary chemosensor in solution. The Lewis basic anions fluoride and hydroxide induce a colour change via a deprotonation mechanism.

Cloning and functional characterization of a tau class glutathione transferase associated with haloxyfop-P-methyl resistance in Digitaria sanguinalis.

BACKGROUND: Haloxyfop-P-methyl, an acetyl-CoA carboxylase (ACCase)-inhibiting herbicide, has been extensively used to control grass weeds. Widespread use of haloxyfop-P-methyl in cotton fields in China has led to the development of glutathione transferase (GST)-mediated resistance in Digitaria sanguinalis. An RNA-seq analysis identified DsGSTU1, a tau class glutathione transferase from the D. sanguinalis transcriptome as a potential candidate. Here, we cloned DsGSTU1 from D. sanguinalis young leaf tissues and subsequently characterized DsGSTU1 by a combination of sequence analysis, as well as functional heterologous expression in rice. RESULTS: The full-length coding DNA sequence (CDS) of DsGSTU1 is 717 bp in length. Higher DsGSTU1 expression was observed in haloxyfop-P-methyl-resistant (HR) D. sanguinalis than in haloxyfop-P-methyl-susceptible (HS) plants. Overexpression of the DsGSTU1 gene was confirmed by transformation into the wild-type (WT) Nipponbare rice with pBWA(V)HS, a recombinant expression vector. GST activity in transgenic rice seedlings was 1.18-1.40-fold higher than the WT rice seedlings before and after haloxyfop-P-methyl treatment, respectively. Additionally, transgenic rice seedlings overexpressing DsGSTU1 were less sensitive to haloxyfop-P-methyl. CONCLUSION: Our combined findings suggest that DsGSTU1 is involved in metabolic resistance to haloxyfop-P-methyl in D. sanguinalis. A better understanding of the major genes contributing to herbicide-resistant D. sanguinalis facilitates the development of resistance management strategies for this global invasive grass weed. © 2023 Society of Chemical Industry.

Multi-omics analyses reveal the crosstalk between the circadian clock and the response to herbicide application in Oryza sativa.

Plants have evolved circadian clock systems that enable biological processes to occur in tandem with periodic changes in the environment. However, it is largely unknown whether crosstalk occurs between the circadian clock and the response to herbicide in rice. We identified 19 conserved rhythmic metabolites which were response to pesticide application and their metabolic abundance peaked mainly at ZT2 or ZT14-ZT18. We found a series of glyphosate, s-Metolachlor, fenclorim, metcamifen and GA3 response genes were expressed following stable circadian rhythms. In order to determine the patterns of their temporal expression, co-expression network analysis was done on 10,467 genes that were periodically expressed throughout a 24-hour period. Next, we identified 4,031 potential direct target genes of OsCCA1 in using DAP-seq data for OsCCA1. Of these, 339, 22, 53, 53 and 63 genes showed a response to glyphosate, s-Metolachlor, fenclorim, metcamifen and GA3 application, respectively. And they were mainly phased from dusk to midnight. Interestingly, we identified significant OsCCA1 binding peaks in the promoter regions of four herbicide resistance genes, including OsCYP81A12, OsCYP81E22, OsCYP76C2, and OsCYP76C4. Finally, we found that herbicide application could affects the expression of some of the central oscillator genes of the rice circadian clock. Here, we used multi-omics data to reveal the crosstalk between the circadian clock and herbicide response processes at the epigenomics, transcriptome, and metabolome levels in rice. This work will serve as a theoretical guide for identifying rhythmic herbicide targets, leading to the creation of new herbicides or the breeding of crops resistant to herbicides.

Interference of Dihydrocoumarin with Hormone Transduction and Phenylpropanoid Biosynthesis Inhibits Barnyardgrass (Echinochloa crus-galli) Root Growth.

Botanical compounds with herbicidal activity exhibit safety, low toxicity, and low chances of herbicide resistance development in plants. They have widespread applications in green agricultural production and the development of organic agriculture. In the present study, dihydrocoumarin showed potential as a botanical herbicide, and its phenotypic characteristics and mechanism of action were studied in barnyardgrass [Echinochloa crus-galli (L.) P.Beauv.] seedlings. The results indicated that dihydrocoumarin inhibited the growth of barnyardgrass without causing significant inhibition of rice seedling growth at concentrations ranging between 0.5 and 1.0 g/L. Additionally, dihydrocoumarin treatment could cause oxidative stress in barnyardgrass, disrupt the cell membrane, and reduce the root cell activity, resulting in root cell death. Transcriptomic analyses revealed that dihydrocoumarin could inhibit barnyardgrass normal growth by affecting the signal transduction of plant hormones. The results showed significant differential expression of plant hormone signal transduction genes in barnyardgrass. Additionally, dihydrocoumarin interfered with the expression of numerous phenylpropanoid biosynthesis genes in barnyardgrass that affect the production of various vital metabolites. We speculate that the barnyardgrass growth was suppressed by the interaction among hormones and phenylpropanoid biosynthesis genes, indicating that dihydrocoumarin can be applied as a bioherbicide to control barnyardgrass growth in rice transplanting fields.

Phenotypic and genotypic characterization of multi-drug resistance Pseudomonas aeruginosa isolated from urinary tract infections of non-catheterized and catheterized Chinese patients: A descriptive study over 3 years.

Urinary tract infections (UTI) are commonest infections, especially in catheterized patients. It is responsible of mortality and morbidity among hospitalized patients. The objectives of the study were to demonstrate the virulence factors and their genes of multi-drug resistance Pseudomonas aeruginosa causing UTI. A total of 366 non-catheterized and 171 catheterized patients' (in whom the catheter was in > 48 hours duration) urine samples (one sample/patient) from both sexes were collected and processed. >105 colony forming unit was considered as Pseudomonas aeruginosa culture-positive. Antimicrobial susceptibility testing was done by the Kirby Bauer disc diffusion method (The Clinical and laboratory standards institute guidelines 2019). The virulence factors were detected by in vitro assay method and polymerase chain reaction was done to detect the resistance genes present in Pseudomonas aeruginosa. Biofilm production was detected by the microtiter plate method. Out of 537 urine samples a total of 280 (52%) were females and 257 (48%) were male patients. Out of 366 non-catheterized urine samples 42 (23.6%) grew Pseudomonas aeruginosa and out of 171 catheterized urine 23 (25.84%) grew Pseudomonas aeruginosa. All were multi-drug resistance strains. A total of 10 (23.80%), 42 (100%), 8 (19.05%), 24 (57.14%), and 36 (85.71%) produced the Metallo-ß-lactamases, AmpC-ß-lactamase, carbapenemase, strong biofilm, and twitching motility positive, respectively in non-catheterized urine samples. A total of 11, 34, 9, 28, and 37 were oxacillinases-23, multidrug efflux protein resistance, New Delhi metallo-ß-lactamase-1, Verona Integron-encoded MBL, and Pseudomonas specific enzyme gene detected in non-catheterized urine samples. A total of 8 (34.8%), 6 (26.01%), 4 (17.39%), 15 (65.2%), and 18 (78.26%) were produced Metallo-ß-lactamases, carbapenemase, AmpC-ß-lactamase, strong biofilm, and twitching motility positive, respectively in catheterized urine samples. A total of 6, 18, 4, 16, and 15 were oxacillinases 23, multidrug efflux protein resistance, New Delhi metallo-ß-lactamase-1, Verona Integron-encoded MBL, and Pseudomonas specific enzyme, respectively genes detected in catheterized urine samples. Biofilm formation and twitching motility showed correlation among culture-positive Pseudomonas aeruginosa strains from catheterized patients (Correlation coefficients = 6.2, 95% confidence interval: 5.4-7.2). A better hospital infection control practice and detailed investigation of the microevolution of Pseudomonas aeruginosa in UTI are needed.

Genomic insights into the origin, adaptive evolution, and herbicide resistance of Leptochloa chinensis, a devastating tetraploid weedy grass in rice fields.

Chinese sprangletop (Leptochloa chinensis), belonging to the grass subfamily Chloridoideae, is one of the most notorious weeds in rice ecosystems. Here, we report a chromosome-scale reference genome assembly and a genomic variation map of the tetraploid L. chinensis. The L. chinensis genome is derived from two diploid progenitors that diverged ∼10.9 million years ago, and its two subgenomes display neither fractionation bias nor overall gene expression dominance. Comparative genomic analyses reveal substantial genome rearrangements in L. chinensis after its divergence from the common ancestor of Chloridoideae and, together with transcriptome profiling, demonstrate the important contribution of tetraploidization to the gene sources for the herbicide resistance of L. chinensis. Population genomic analyses of 89 accessions from China reveal that L. chinensis accessions collected from southern/southwestern provinces have substantially higher nucleotide diversity than those from the middle and lower reaches of the Yangtze River, suggesting that L. chinensis spread in China from the southern/southwestern provinces to the middle and lower reaches of the Yangtze River. During this spread, L. chinensis developed significantly increased herbicide resistance, accompanied by the selection of numerous genes involved in herbicide resistance. Taken together, our study generated valuable genomic resources for future fundamental research and agricultural management of L. chinensis, and provides significant new insights into the herbicide resistance as well as the origin and adaptive evolution of L. chinensis.