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Dinuclear monooxygenases mediate challenging C-H bond oxidation reactions throughout nature. Many of these enzymes are presumed to exclusively utilize diiron cofactors. Herein we report the bioinformatic discovery of an orphan dinuclear monooxygenase that preferentially utilizes a heterobimetallic manganese-iron (Mn/Fe) cofactor to mediate an O 2 -dependent C-H bond hydroxylation reaction. Unlike the structurally similar Mn/Fe-dependent monooxygenase AibH2, the diiron form of this enzyme (SfbO) exhibits a nascent enzymatic activity. This behavior raises the possibility that many other dinuclear monooxygenases may be endowed with the capacity to harness cofactors with a variable metal content.

Crop engineering and de novo domestication using gene editing are new frontiers in agriculture. However, outside of well-studied crops and model systems, prioritizing engineering targets remains challenging. Evolution can guide us, revealing genes with deeply conserved roles that have repeatedly been selected in the evolution of plant form. Homologs of the transcription factor genes GRASSY TILLERS1 ( GT1 ) and SIX-ROWED SPIKE1 ( VRS1 ) have repeatedly been targets of selection in domestication and evolution, where they repress growth in many developmental contexts. This suggests a conserved role for these genes in regulating growth repression. To test this, we determined the roles of GT1 and VRS1 homologs in maize ( Zea mays ) and the distantly related grass brachypodium ( Brachypodium distachyon ) using gene editing and mutant analysis. In maize, gt1; vrs1-like1 ( vrl1 ) mutants have derepressed growth of floral organs. In addition, gt1; vrl1 mutants bore more ears and more branches, indicating broad roles in growth repression. In brachypodium, Bdgt1; B dvrl1 mutants have more branches, spikelets, and flowers than wild-type plants, indicating conserved roles for GT1 and VRS1 homologs in growth suppression over ca. 59 My of grass evolution. Importantly, many of these traits influence crop productivity. Notably, maize GT1 can suppress growth in arabidopsis ( Arabidopsis thaliana ) floral organs, despite ca . 160 My of evolution separating the grasses and arabidopsis. Thus, GT1 and VRS1 maintain their potency as growth regulators across vast timescales and in distinct developmental contexts. This work highlights the power of evolution to inform gene editing in crop improvement., Competing Interests: Competing interests statement:The authors declare no competing interest.

The aerobic oxidation of carbon-hydrogen (C-H) bonds in biology is currently known to be accomplished by a limited set of cofactors that typically include heme, nonheme iron, and copper. While manganese cofactors perform difficult oxidation reactions, including water oxidation within Photosystem II, they are generally not known to be used for C-H bond activation, and those that do catalyze this important reaction display limited intrinsic reactivity. Here we report that the 2-aminoisobutyric acid hydroxylase from Rhodococcus wratislaviensis , AibH1H2, requires manganese to functionalize a strong, aliphatic C-H bond (BDE = 100 kcal/mol). Structural and spectroscopic studies of this enzyme reveal a redox-active, heterobimetallic manganese-iron active site at the locus of O 2 activation and substrate coordination. This result expands the known reactivity of biological manganese-iron cofactors, which was previously restricted to single-electron transfer or stoichiometric protein oxidation. Furthermore, the AibH1H2 cofactor is supported by a protein fold distinct from typical bimetallic oxygenases, and bioinformatic analyses identify related proteins abundant in microorganisms. This suggests that many uncharacterized monooxygenases may similarly require manganese to perform oxidative biochemical tasks.

Manganese cofactors activate strong chemical bonds in many essential enzymes. Yet very few manganese-dependent enzymes are known to functionalize ubiquitous carbon-hydrogen (C-H) bonds, and those that catalyze this important reaction display limited intrinsic reactivity. Herein, we report that the 2-aminoisobutyric acid hydroxylase from Rhodococcus wratislaviensis requires manganese to functionalize a C-H bond possessing a bond dissociation enthalpy (BDE) exceeding 100 kcal/mol. Structural and spectroscopic studies of this enzyme reveal a redox-active, heterobimetallic manganese-iron active site that utilizes a manganese ion at the locus for O 2 activation and substrate coordination. Accordingly, this enzyme represents the first documented Mn-dependent monooxygenase in biology. Related proteins are widespread in microorganisms suggesting that many uncharacterized monooxygenases may utilize manganese-containing cofactors to accomplish diverse biological tasks.

Wastewater-based epidemiology has emerged as a promising technology for population-level surveillance of COVID-19. In this study, we present results of a large nationwide SARS-CoV-2 wastewater monitoring system in the United States. We profile 55 locations with at least six months of sampling from April 2020 to May 2021. These locations represent more than 12 million individuals across 19 states. Samples were collected approximately weekly by wastewater treatment utilities as part of a regular wastewater surveillance service and analyzed for SARS-CoV-2 RNA concentrations. SARS-CoV-2 RNA concentrations were normalized to pepper mild mottle virus, an indicator of fecal matter in wastewater. We show that wastewater data reflect temporal and geographic trends in clinical COVID-19 cases and investigate the impact of normalization on correlations with case data within and across locations. We also provide key lessons learned from our broad-scale implementation of wastewater-based epidemiology, which can be used to inform wastewater-based epidemiology approaches for future emerging diseases. This work demonstrates that wastewater surveillance is a feasible approach for nationwide population-level monitoring of COVID-19 disease. With an evolving epidemic and effective vaccines against SARS-CoV-2, wastewater-based epidemiology can serve as a passive surveillance approach for detecting changing dynamics or resurgences of the virus., Competing Interests: The authors declare the following competing financial interest(s): C.D., K.A.M., N.E., M.I., R.F.-O., M.M.P., S.M., S.T.W., F.C., T.M., C.L.S., and S.W.O. are current or former employees of Biobot Analytics, Inc. E.J.A. is scientific advisor to Biobot Analytics, Inc., (© 2022 The Authors. Published by American Chemical Society.)

Schizophrenia is a severe mental disorder with various medical comorbidities and early mortality. Hyperprolactinemia is common in women and its impact on sexual function, galactorrhea and amenorrhea is well known. This paper evaluates the risk of 25-hydroxy vitamin D deficiency and other metabolic related laboratory abnormalities in women with schizophrenia having hyperprolactinemia (N = 43). The mean prolactin level in these women was 88.5 ± 56.0 ng/mL. We found that 100% of women were overweight of which 74% (32/43) of the women were obese, 56% (23/41) had abnormal total cholesterol levels and 30% (13/43) had high fasting blood glucose. Vitamin D levels were considered deficient or inadequate in 37% of women. We did not see significant correlations of prolactin with laboratory measures, however all female patients had elevated and high prolactin levels, leading to low variability in a small sample, which may have precluded seeing any direct relationships. Recognizing prolactin related side effects and understanding the role of other health measures seen in women with antipsychotic induced hyperprolactinemia in our female patients are critical steps toward better personalization of their care and recovery., (Copyright © 2022. Published by Elsevier Ltd.)

Permafrost degradation is delivering bioavailable dissolved organic matter (DOM) and inorganic nutrients to surface water networks. While these permafrost subsidies represent a small portion of total fluvial DOM and nutrient fluxes, they could influence food webs and net ecosystem carbon balance via priming or nutrient effects that destabilize background DOM. We investigated how addition of biolabile carbon (acetate) and inorganic nutrients (nitrogen and phosphorus) affected DOM decomposition with 28-day incubations. We incubated late-summer stream water from 23 locations nested in seven northern or high-altitude regions in Asia, Europe, and North America. DOM loss ranged from 3% to 52%, showing a variety of longitudinal patterns within stream networks. DOM optical properties varied widely, but DOM showed compositional similarity based on Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis. Addition of acetate and nutrients decreased bulk DOM mineralization (i.e., negative priming), with more negative effects on biodegradable DOM but neutral or positive effects on stable DOM. Unexpectedly, acetate and nutrients triggered breakdown of colored DOM (CDOM), with median decreases of 1.6% in the control and 22% in the amended treatment. Additionally, the uptake of added acetate was strongly limited by nutrient availability across sites. These findings suggest that biolabile DOM and nutrients released from degrading permafrost may decrease background DOM mineralization but alter stoichiometry and light conditions in receiving waterbodies. We conclude that priming and nutrient effects are coupled in northern aquatic ecosystems and that quantifying two-way interactions between DOM properties and environmental conditions could resolve conflicting observations about the drivers of DOM in permafrost zone waterways., (©2020. The Authors.)

This study investigates clinically valid signals about psychiatric symptoms in social media data, by rating severity of psychiatric symptoms in donated, de-identified Facebook posts and comparing to in-person clinical assessments. Participants with schizophrenia (N=8), depression (N=7), or who were healthy controls (N=8) also consented to the collection of their Facebook activity from three months before the in-person assessments to six weeks after this evaluation. Depressive symptoms were assessed in- person using the Montgomery-Åsberg Depression Rating Scale (MADRS), psychotic symptoms were assessed using the Brief Psychiatric Rating Scale (BPRS), and global functioning was assessed using the Community Assessment of Psychotic Experiences (CAPE-42). Independent raters (psychiatrists, non-psychiatrist mental health clinicians, and two staff members) rated depression, psychosis, and global functioning symptoms from the social media activity of deidentified participants. The correlations between in-person clinical ratings and blinded ratings based on social media data were evaluated. Significant correlations (and trends for significance in the mixed model controlling for multiple raters) were found for psychotic symptoms, global symptom ratings and depressive symptoms. Results like these, indicating the presence of clinically valid signal in social media, are an important step toward developing computational tools that could assist clinicians by providing additional data outside the context of clinical encounters., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Approximately one-third of people with schizophrenia have elevated levels of anti-gliadin antibodies of the immunoglobulin G type (AGA IgG) — a higher rate than seen in healthy controls. We performed the first double-blind clinical trial of gluten-free versus gluten-containing diets in a subset of patients with schizophrenia who were positive for AGA IgG., Methods: In this pilot feasibility study, 16 participants with schizophrenia or schizoaffective disorder who had elevated AGA IgG (≥ 20 U) but were negative for celiac disease were admitted to an inpatient unit for a 5-week trial. All participants received standardized gluten-free meals and were randomized in a double-blind fashion to receive a shake containing 10 g of gluten flour or 10 g of rice flour each day. Participants were rated for psychiatric, cognitive and gastrointestinal symptoms at baseline and endpoint., Results: Of the 16 participants, 14 completed the 5-week trial (2 discontinued early for administrative reasons). Compared with participants on the gluten-containing diet, participants on the gluten-free diet showed improvement on the Clinical Global Impressions scale (Cohen d = –0.75) and in negative symptoms (Cohen d = –0.53). We noted no improvement in positive or global cognitive symptoms, but did observe an improvement in attention favouring the gluten-free diet (Cohen d = 0.60). Robust improvements in gastrointestinal adverse effects occurred in the gluten-free group relative to the glutencontaining group. Adverse effects were similar between groups., Limitations: This study was limited by its small sample size; larger studies are needed., Conclusion: This feasibility study suggests that removal of gluten from the diet is associated with improvement in psychiatric and gastrointestinal symptoms in people with schizophrenia or schizoaffective disorder., Competing Interests: D. Kelly served as an advisor to Lundbeck and HLS Therapeutics. A. Fasano is the founder and a stock holder of Alba Therapeutics. R. Buchanan served on the advisory boards for Astellas Pharma, Avanir, Boehringer Ingelheim-RCV, ITI, Inc., Lundbeck and Roche. He was a consultant for Takeda and Upsher-Smith Laboratories and on the DSMB for Pfizer. W. Carpenter has served as an advisor to Boehringer Ingelheim, Allergan, Health Analytics and Teva. All other authors have nothing to disclose., (© 2019 Joule Inc. or its licensors)

Cytochrome P450 enzymes generally functionalize inert C-H bonds, and thus, they are important biocatalysts for chemical synthesis. However, enzymes that catalyze both aliphatic and aromatic hydroxylation in the same biotransformation process have rarely been reported. A recent biochemical study demonstrated the P450 TxtC for the biosynthesis of herbicidal thaxtomins as the first example of this unique type of enzyme. Herein, the detailed characterization of substrate requirements and biocatalytic applications of TxtC are reported. The results reveal the importance of N-methylation of the thaxtomin diketopiperazine (DKP) core on enzyme reactions and demonstrate the tolerance of the enzyme to modifications on the indole and phenyl moieties of its substrates. Furthermore, hydroxylated, methylated, aromatic DKPs are synthesized through a biocatalytic route comprising TxtC and the promiscuous N-methyltransferase Amir_4628; thus providing a basis for the broad application of this unique P450., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Purpose/background: Prolactin-related adverse effects contribute to nonadherence and adverse health consequences, particularly in women with severe mental illness. Treating these adverse effects may improve treatment acceptability, adherence, and long-term outcomes., Methods/procedures: Premenopausal women with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision diagnosis of schizophrenia, schizoaffective disorder, or bipolar disorder were recruited for a randomized, double-blind, placebo-controlled 16-week trial of adjunct aripiprazole (5-15 mg/d). Participants had elevated prolactin (>24 ng/mL) and were experiencing galactorrhea, amenorrhea, oligomenorrhea, or sexual dysfunction on a prolactin-elevating antipsychotic. Participants were evaluated biweekly for prolactin elevation and galactorrhea and completed a menstrual diary review. Psychiatric symptoms and adverse effects were closely monitored., Findings/results: Forty-six women were randomized (n = 25 aripiprazole, n = 21 placebo). Thirty-seven completed at least 8 weeks of the study (n = 20 [80%] aripiprazole and n = 17 [81%] placebo). Aripiprazole (mean dose, 11.7 ± 2.4 mg/d) was effective for lowering prolactin relative to placebo (P = 0.04). In addition, 45% (9/20) of the aripiprazole group had a normalized prolactin (<24 mg/mL) compared with 12% (2/17) of the placebo group (P = 0.028). Galactorrhea resolved in 77% (10/13) of the aripiprazole-treated participants compared with 33% (4/12) in the placebo group (P = 0.028). Normalization of sexual function (<16 on the Arizona Sexual Experience Scale) occurred in 50% on aripiprazole (7/14) versus 9% (1/11) on placebo (P = 0.030). No differences between groups in symptoms or adverse effects were noted. Overall, women rated a mean score of 4.6 ± 0.6 on a 5-point Likert scale for sexual function improvement, suggesting their particular satisfaction with improvement in this domain., Implications/conclusions: Building upon prior studies, this rigorous evaluation confirms the utility of adjunctive aripiprazole as a strategy for improving prolactin and managing prolactin-related adverse effects in premenopausal women with psychosis.

Thaxtomins are virulence factors of most plant-pathogenic Streptomyces strains. Due to their potent herbicidal activity, attractive environmental compatibility, and inherent biodegradability, thaxtomins are key active ingredients of bioherbicides approved by the U.S. Environmental Protection Agency. However, the low yield of thaxtomins in native Streptomyces producers limits their wide agricultural applications. Here, we describe the high-yield production of thaxtomins in a heterologous host. The thaxtomin gene cluster from S. scabiei 87.22 was cloned and expressed in S. albus J1074 after chromosomal integration. The production of thaxtomins and nitrotryptophan analogs was observed using liquid chromatography-mass spectrometry (LC-MS) analysis. When the engineered S. albus J1074 was cultured in the minimal medium Thx defined medium supplemented with 1% cellobiose (TDMc), the yield of the most abundant and herbicidal analog, thaxtomin A, was 10 times higher than that in S. scabiei 87.22, and optimization of the medium resulted in the highest yield of thaxtomin analogs at about 222 mg/liter. Further engineering of the thaxtomin biosynthetic gene cluster through gene deletion led to the production of multiple biosynthetic intermediates important to the chemical synthesis of new analogs. Additionally, the versatility of the thaxtomin biosynthetic system in S. albus J1074 was capitalized on to produce one unnatural fluorinated analog, 5-fluoro-thaxtomin A (5-F-thaxtomin A), whose structure was elucidated by a combination of MS and one-dimensional (1D) and 2D nuclear magnetic resonance (NMR) analyses. Natural and unnatural thaxtomins demonstrated potent herbicidal activity in radish seedling assays. These results indicated that S. albus J1074 has the potential to produce thaxtomins and analogs thereof with high yield, fostering their agricultural applications. IMPORTANCE Thaxtomins are agriculturally valuable herbicidal natural products, but the productivity of native producers is limiting. Heterologous expression of the thaxtomin gene cluster in S. albus J1074 resulted in the highest yield of thaxtomins ever reported, representing a significant leap forward in its wide agricultural use. Furthermore, current synthetic routes to thaxtomins and analogs are lengthy, and two thaxtomin biosynthetic intermediates produced at high yields in this work can provide precursors and building blocks to advanced synthetic routes. Importantly, the production of 5-F-thaxtomin A in engineered S. albus J1074 demonstrated a viable alternative to chemical methods in the synthesis of new thaxtomin analogs. Moreover, our work presents an attractive synthetic biology strategy to improve the supply of herbicidal thaxtomins, likely finding general applications in the discovery and production of many other bioactive natural products., (Copyright © 2018 American Society for Microbiology.)

We evaluated the analytical performance of the "SimulTROPIN" (Becton-Dickinson Inc.) radioimmunoassay for the simultaneous measurement of lutropin (LH) and follitropin (FSH) in human serum. Dose response, linearity, analytical recovery, sensitivity, and reagent stability were all acceptable. Cross reactivity with other structurally related hormones [choriogonadotropin (CG) and thyrotropin (TSH)] was minimal. A normal reference interval was established for nonmidcycle, ovulatory women. We confirm the low degree of CG and TSH cross reactivity with LH and FSH reported by Becton Dickinson and conclude that this assay is an acceptable method for laboratory use in the simultaneous quantification of these analytes.