Modifying the Steric Properties in the Second Coordination Sphere of Designed Peptides Leads to Enhancement of Nitrite Reductase Activity

Protein design is a useful strategy to interrogate the protein structureâ function relationship. We demonstrate using a highly modular 3â stranded coiled coil (TRIâ peptide system) that a functional typeâ 2 copper center exhibiting copper nitrite reductase (NiR) activity exhibits the highest homogeneous catalytic efficiency under aqueous conditions for the reduction of nitrite to NO and H2O. Modification of the amino acids in the second coordination sphere of the copper center increases the nitrite reductase activity up to 75â fold compared to previously reported systems. We find also that steric bulk can be used to enforce a threeâ coordinate CuI in a site, which tends toward twoâ coordination with decreased steric bulk. This study demonstrates the importance of the second coordination sphere environment both for controlling metalâ center ligation and enhancing the catalytic efficiency of metalloenzymes and their analogues.Erstklassiges aus der zweiten Reihe: Die Aktivität der Nitritreduktase kann durch Modifikation der sterischen Eigenschaften in der zweiten Koordinationssphäre eines Typâ 2â Kupferzentrums deutlich erhöht werden. à ber die Sterik lassen sich die Koordination und Reaktivität des Metalls in einem dreisträngigen â Coiledâ coilâ â TRIâ Peptidgerüst (TRIWâ H) vorgeben.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142882/1/ange201712757_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142882/2/ange201712757-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142882/3/ange201712757.pd

Modifying the Steric Properties in the Second Coordination Sphere of Designed Peptides Leads to Enhancement of Nitrite Reductase Activity

Protein design is a useful strategy to interrogate the protein structureâ function relationship. We demonstrate using a highly modular 3â stranded coiled coil (TRIâ peptide system) that a functional typeâ 2 copper center exhibiting copper nitrite reductase (NiR) activity exhibits the highest homogeneous catalytic efficiency under aqueous conditions for the reduction of nitrite to NO and H2O. Modification of the amino acids in the second coordination sphere of the copper center increases the nitrite reductase activity up to 75â fold compared to previously reported systems. We find also that steric bulk can be used to enforce a threeâ coordinate CuI in a site, which tends toward twoâ coordination with decreased steric bulk. This study demonstrates the importance of the second coordination sphere environment both for controlling metalâ center ligation and enhancing the catalytic efficiency of metalloenzymes and their analogues.Second is best: A significant increase in nitrite reductase activity is achieved by modification of the steric properties of the second coordination sphere of a typeâ 2 copper center. The steric properties can be harnessed to control metal coordination and reactivity in a 3â stranded coiled coil TRI peptide scaffold (TRIWâ H).Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142897/1/anie201712757.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142897/2/anie201712757-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142897/3/anie201712757_am.pd

Stroke Ready: a multi-level program that combines implementation science and community-based participatory research approaches to increase acute stroke treatment: protocol for a stepped wedge trial

Abstract Background Post-stroke disability is common, costly, and projected to increase. Acute stroke treatments can substantially reduce post-stroke disability, but few patients take advantage of these cost-effective treatments. Practical, cost-efficient, and sustainable interventions to address underutilized acute stroke treatments are currently lacking. In this context, we present the Stroke Ready project, a stepped wedge design, multi-level intervention that combines implementation science and community-based participatory research approaches to increase acute stroke treatments in the predominately African American community of Flint, Michigan, USA. Methods Guided by the Tailored Implementation of Chronic Disease (TICD) framework, we begin with optimization of acute stroke care in emergency departments, with particular attention given to our safety-net hospital partners. Then, we move to a community-wide, multi-faceted, stroke preparedness intervention, with workshops led by peer educators, over 2 years. Measures of engagement of the safety-net hospital and the feasibility and sustainability of the implementation strategy as well as community intervention reach, dose delivered, and satisfaction will be collected. The primary outcome is acute stroke treatment rates, which includes both intravenous tissue plasminogen activator, and endovascular treatment. The co-secondary outcomes are intravenous tissue plasminogen activator treatment rates and the proportion of stroke patients who arrive by ambulance. Discussion If successful, Stroke Ready will increase acute stroke treatment rates through emergency department and community level interventions. The stepped wedge design and process evaluation will provide insight into how Stroke Ready works and where it might work best. By exploring the relative effectiveness of the emergency department optimization and the community intervention, we will inform hospitals and communities as they determine how best to use their resources to optimize acute stroke care. Trial registration ClinicalTrials.gov Trial Identifier NCT03645590 .https://deepblue.lib.umich.edu/bitstream/2027.42/148211/1/13012_2019_Article_869.pd

Mammary molecular portraits reveal lineage-specific features and progenitor cell vulnerabilities.

The mammary epithelium depends on specific lineages and their stem and progenitor function to accommodate hormone-triggered physiological demands in the adult female. Perturbations of these lineages underpin breast cancer risk, yet our understanding of normal mammary cell composition is incomplete. Here, we build a multimodal resource for the adult gland through comprehensive profiling of primary cell epigenomes, transcriptomes, and proteomes. We define systems-level relationships between chromatin-DNA-RNA-protein states, identify lineage-specific DNA methylation of transcription factor binding sites, and pinpoint proteins underlying progesterone responsiveness. Comparative proteomics of estrogen and progesterone receptor-positive and -negative cell populations, extensive target validation, and drug testing lead to discovery of stem and progenitor cell vulnerabilities. Top epigenetic drugs exert cytostatic effects; prevent adult mammary cell expansion, clonogenicity, and mammopoiesis; and deplete stem cell frequency. Select drugs also abrogate human breast progenitor cell activity in normal and high-risk patient samples. This integrative computational and functional study provides fundamental insight into mammary lineage and stem cell biology

Individual common variants exert weak effects on the risk for autism spectrum disorders.

While it is apparent that rare variation can play an important role in the genetic architecture of autism spectrum disorders (ASDs), the contribution of common variation to the risk of developing ASD is less clear. To produce a more comprehensive picture, we report Stage 2 of the Autism Genome Project genome-wide association study, adding 1301 ASD families and bringing the total to 2705 families analysed (Stages 1 and 2). In addition to evaluating the association of individual single nucleotide polymorphisms (SNPs), we also sought evidence that common variants, en masse, might affect the risk. Despite genotyping over a million SNPs covering the genome, no single SNP shows significant association with ASD or selected phenotypes at a genome-wide level. The SNP that achieves the smallest P-value from secondary analyses is rs1718101. It falls in CNTNAP2, a gene previously implicated in susceptibility for ASD. This SNP also shows modest association with age of word/phrase acquisition in ASD subjects, of interest because features of language development are also associated with other variation in CNTNAP2. In contrast, allele scores derived from the transmission of common alleles to Stage 1 cases significantly predict case status in the independent Stage 2 sample. Despite being significant, the variance explained by these allele scores was small (Vm< 1%). Based on results from individual SNPs and their en masse effect on risk, as inferred from the allele score results, it is reasonable to conclude that common variants affect the risk for ASD but their individual effects are modest

Long Covid in adults discharged from UK hospitals after Covid-19 : a prospective, multicentre cohort study using the ISARIC WHO Clinical Characterisation Protocol

Funding: This work is supported by grants from: the National Institute for Health Research (NIHR) [award CO-CIN-01], the Medical Research Council [grant MC_PC_19059], the Imperial Biomedical Research Centre (NIHR Imperial BRC, grant P45058), the Health Protection Research Unit (HPRU) in Respiratory Infections at Imperial College London and NIHR HPRU in Emerging and Zoonotic Infections at University of Liverpool, both in partnership with Public Health England, [NIHR award 200907], Wellcome Trust and Department for International Development [215091/Z/18/Z], and the Bill and Melinda Gates Foundation [OPP1209135], and Liverpool Experimental Cancer Medicine Centre (Grant Reference: C18616/A25153), NIHR Biomedical Research Centre at Imperial College London [IS-BRC-1215-20013], EU Platform for European Preparedness Against (Re-) emerging Epidemics 1 [FP7 project 602525] and NIHR Clinical Research Network for providing infrastructure support for this research. LT is a Wellcome Trust clinical career development fellow, supported by grant number 205228/Z/16/Z. This research was funded in part, by the Wellcome Trust. PJMO is supported by a NIHR Senior Investigator Award [award 201385].Background : This study sought to establish the long-term effects of Covid-19 following hospitalisation. Methods : 327 hospitalised participants, with SARS-CoV-2 infection were recruited into a prospective multicentre cohort study at least 3 months post-discharge. The primary outcome was self-reported recovery at least ninety days after initial Covid-19 symptom onset. Secondary outcomes included new symptoms, disability (Washington group short scale), breathlessness (MRC Dyspnoea scale) and quality of life (EQ5D-5L). Findings : 55% of participants reported not feeling fully recovered. 93% reported persistent symptoms, with fatigue the most common (83%), followed by breathlessness (54%). 47% reported an increase in MRC dyspnoea scale of at least one grade. New or worse disability was reported by 24% of participants. The EQ5D-5L summary index was significantly worse following acute illness (median difference 0.1 points on a scale of 0 to 1, IQR: -0.2 to 0.0). Females under the age of 50 years were five times less likely to report feeling recovered (adjusted OR 5.09, 95% CI 1.64 to 15.74), were more likely to have greater disability (adjusted OR 4.22, 95% CI 1.12 to 15.94), twice as likely to report worse fatigue (adjusted OR 2.06, 95% CI 0.81 to 3.31) and seven times more likely to become more breathless (adjusted OR 7.15, 95% CI 2.24 to 22.83) than men of the same age. Interpretation : Survivors of Covid-19 experienced long-term symptoms, new disability, increased breathlessness, and reduced quality of life. These findings were present in young, previously healthy working age adults, and were most common in younger females.Publisher PDFPeer reviewe