Assessing substrate scope of the cyclodehydratase LynD by mRNA display-enabled machine learning models.

Many of the biosynthetic pathways for ribosomal synthesized and post-translationally modified peptide (RiPP) natural products make use of multi-domain enzymes with separate recruitment and catalysis domains that separately bind and modify peptide substrates. This "division of labor" allows RiPP enzymes to use relatively open and promiscuous active sites to perform chemistry at multiple residues within a peptide substrate seemingly regardless of the surrounding context. Defining, measuring, and predicting the seemingly broad substrate promiscuity of RiPPs necessitates high throughput assays, capable of assessing activity against very large libraries of peptides.

Cheminformatics-Guided Cell-Free Exploration of Peptide Natural Products.

There have been significant advances in the flexibility and power of cell-free translation systems. The increasing ability to incorporate noncanonical amino acids and complement translation with recombinant enzymes has enabled cell-free production of peptide-based natural products (NPs) and NP-like molecules. We anticipate that many more such compounds and analogs might be accessed in this way.

Staff experiences of the use of virtual consultations in non-surgical oncology systemic anticancer therapy services.

Purpose: In response to the COVID-19 pandemic, virtual consultations were introduced rapidly across cancer services. This created a particular set of challenges for systemic anticancer therapy services, where patients have frequent, regular appointments to support decision-making regarding treatment. This study explores the experiences of staff who provide these consultations to understand the implications for patients, staff, and services.

Production of Ethyl-agarobioside, a Novel Skin Moisturizer, by Mimicking the Alcoholysis from the Japanese Sake-Brewing Process.

Agarobiose (AB; d-galactose-β-1,4-AHG), produced by one-step acid hydrolysis of agarose of red seaweed, is considered a promising cosmetic ingredient due to its skin-moisturizing activity. In this study, the use of AB as a cosmetic ingredient was found to be hampered due to its instability at high temperature and alkaline pH. Therefore, to increase the chemical stability of AB, we devised a novel process to synthesize ethyl-agarobioside (ethyl-AB) from the acid-catalyzed alcoholysis of agarose.

Data on vegetation across forest edges from the FERN (Forest Edge Research Network).

Many studies have focused on vegetation across forest edges to study impacts of edges created by human activities on forest structure and composition, or patterns of vegetation at inherent natural edges. Our objective was to create a database of plant-related variables across different types of edges from various studies (mainly from across Canada, but also in Brazil and Belize) to facilitate edge research. We compiled data on vegetation along more than 300 transects perpendicular to forest edges adjacent to clear-cuts, burned areas, bogs, lakes, barrens, insect disturbances, and riparian areas from 24 studies conducted over the past three decades.

Funneled Depolymerization of Ionic Liquid-Based Biorefinery "Heterogeneous" Lignin into Guaiacols over Reusable Palladium Catalyst.

The efficient utilization of lignin, the direct source of renewable aromatics, into value-added renewable chemicals is an important step towards sustainable biorefinery practices. Nevertheless, owing to the random heterogeneous structure and limited solubility, lignin utilization has been primarily limited to burning for energy. The catalytic depolymerization of lignin has been proposed and demonstrated as a viable route to sustainable biorefinery, however, low yields and poor selectivity of products, high char formation, and limited to no recycling of transition-metal-based catalyst involved in lignin depolymerization demands attention to enable practical-scale lignocellulosic biorefineries.

Enabling Genetic Code Expansion and Peptide Macrocyclization in mRNA Display via a Promiscuous Orthogonal Aminoacyl-tRNA Synthetase.

mRNA display is revolutionizing peptide drug discovery through its ability to quickly identify potent peptide binders of therapeutic protein targets. Methods to expand the chemical diversity of display libraries are continually needed to increase the likelihood of identifying clinically relevant peptide ligands. Orthogonal aminoacyl-tRNA synthetases (ORSs) have proven utility in cellular genetic code expansion, but are relatively underexplored for translation (IVT) and mRNA display.

Enzymatic Pyridine Aromatization during Thiopeptide Biosynthesis.

Thiazole-containing pyritides (thiopeptides) are ribosomally synthesized and post-translationally modified peptides (RiPPs) that have attracted interest owing to their potent biological activities and structural complexity. The class-defining feature of a thiopeptide is a six-membered, nitrogenous heterocycle formed by an enzymatic [4 + 2]-cycloaddition. In rare cases, piperidine or dehydropiperidine (DHP) is present; however, the aromatized pyridine is considerably more common.

A saturation-mutagenesis analysis of the interplay between stability and activation in Ras.

Cancer mutations in Ras occur predominantly at three hotspots: Gly 12, Gly 13, and Gln 61. Previously, we reported that deep mutagenesis of H-Ras using a bacterial assay identified many other activating mutations (Bandaru et al., 2017).

Reaction pathway engineering converts a radical hydroxylase into a halogenase.

Fe/α-ketoglutarate (Fe/αKG)-dependent enzymes offer a promising biocatalytic platform for halogenation chemistry owing to their ability to functionalize unactivated C-H bonds. However, relatively few radical halogenases have been identified to date, limiting their synthetic utility. Here, we report a strategy to expand the palette of enzymatic halogenation by engineering a reaction pathway rather than substrate selectivity.

Environment and coordination of FeMo-co in the nitrogenase metallochaperone NafY.

In nitrogenase biosynthesis, the iron-molybdenum cofactor (FeMo-co) is externally assembled at scaffold proteins and delivered to the NifDK nitrogenase component by the NafY metallochaperone. Here we have used nuclear magnetic resonance, molecular dynamics, and functional analysis to elucidate the environment and coordination of FeMo-co in NafY. H stands as the key FeMo-co ligand.

Biological upgrading of 3,6-anhydro-L-galactose from agarose to a new platform chemical.

Recently, the utilization of renewable biomass instead of fossil fuels for producing fuels and chemicals is receiving much attention due to the global climate change. Among renewable biomass, marine algae are gaining importance as third generation biomass feedstocks owing to their advantages over lignocellulose. Particularly, red macroalgae have higher carbohydrate contents and simpler carbohydrate compositions than other marine algae.

Coronary Artery Bypass Grafting Versus Percutaneous Coronary Intervention in Patients with Left Ventricular Systolic Dysfunction.

Purpose: There is a paucity of comparative data examining the optimal revascularization strategy in patients with left ventricular systolic dysfunction (LVD).

Methods: We performed an aggregate data meta-analysis of clinical outcomes comparing percutaneous coronary intervention (PCI) versus coronary artery bypass (CABG) in patients with LVD (left ventricle ejection fraction (LVEF) of ≤ 40%), using the random effects model. Effects size is reported as odds ratio (OR) and a 95% confidence interval.

Evaluation of reproducible and transparent research practices in pulmonology.

Background: Study reproducibility is valuable for validating or refuting results. Provision of reproducibility indicators, such as materials, protocols, and raw data in a study improve its potential for reproduction. Efforts to reproduce noteworthy studies in the biomedical sciences have resulted in an overwhelming majority of them being found to be unreplicable, causing concern for the integrity of research in other fields, including medical specialties.

Hypothyroidism-associated angioedema.

We present a 41-year-old woman with hypothyroidism who presented to the emergency department with acute onset of angioedema and profound hypothyroidism. She required complex airway management and medical treatment before being discharged home 10 days later. This may be the first case of hypothyroidism-induced angioedema that was not associated with chronic urticaria or hives.

A family of radical halogenases for the engineering of amino-acid-based products.

The integration of synthetic and biological catalysis enables new approaches to the synthesis of small molecules by combining the high selectivity of enzymes with the reaction diversity offered by synthetic chemistry. While organohalogens are valued for their bioactivity and utility as synthetic building blocks, only a handful of enzymes that carry out the regioselective halogenation of unactivated [Formula: see text] bonds have previously been identified. In this context, we report the structural characterization of BesD, a recently discovered radical halogenase from the Fe/α-ketogluturate-dependent family that chlorinates the free amino acid lysine.

Middle Colic Artery Originating from the Gastroduodenal Artery Discovered during a Whipple.

Hepatic artery variations occur in about one-fourth of the population, are frequent questions on standardized surgery exams, and are often discussed on teaching rounds with an attending surgeon. Intraoperatively, it is important to be aware of possible vascular anomalies in order to prevent ligation or injury of an essential vessel. This case report describes an extremely rare vascular anomaly encountered during a pancreaticoduodenectomy (Whipple operation).

Discovery of a pathway for terminal-alkyne amino acid biosynthesis.

Living systems can generate an enormous range of cellular functions, from mechanical infrastructure and signalling networks to enzymatic catalysis and information storage, using a notably limited set of chemical functional groups. This observation is especially notable when compared to the breadth of functional groups used as the basis for similar functions in synthetically derived small molecules and materials. The relatively small cross-section between biological and synthetic reactivity space forms the foundation for the development of bioorthogonal chemistry, in which the absence of a pair of reactive functional groups within the cell allows for a selective in situ reaction.

Unconstrained peptoid tetramer exhibits a predominant conformation in aqueous solution.

Conformational control in peptoids, N-substituted glycines, is crucial for the design and synthesis of biologically-active compounds and atomically-defined nanomaterials. While there are a growing number of structural studies in solution, most have been performed with conformationally-constrained short sequences (e.g.

Entropy drives selective fluorine recognition in the fluoroacetyl-CoA thioesterase from .

Fluorinated small molecules play an important role in the design of bioactive compounds for a broad range of applications. As such, there is strong interest in developing a deeper understanding of how fluorine affects the interaction of these ligands with their targets. Given the small number of fluorinated metabolites identified to date, insights into fluorine recognition have been provided almost entirely by synthetic systems.

Survey of solution dynamics in Src kinase reveals allosteric cross talk between the ligand binding and regulatory sites.

The catalytic domain of protein tyrosine kinases can interconvert between active and inactive conformations in response to regulatory inputs. We recently demonstrated that Src kinase features an allosteric network that couples substrate-binding sites. However, the extent of conformational and dynamic changes that are propagated throughout the kinase domain remains poorly understood.

An Interdisciplinary Approach to Reducing Length of Stay in Joint Replacement Patients.

Demand for hip and knee arthroplasty in the United States is rising rapidly. This is creating considerable strain on healthcare systems' institutional resources and finances. To reduce this strain, Spectrum Health in Grand Rapids, MI, developed a strategy to decrease length of stay for most primary hip and knee joint replacement patients.

A facile method for expression and purification of (15)N isotope-labeled human Alzheimer's β-amyloid peptides from E. coli for NMR-based structural analysis.

Alzheimer's disease (AD) is a progressive neurodegenerative disease affecting millions of people worldwide. AD is characterized by the presence of extracellular plaques composed of aggregated/oligomerized β-amyloid peptides with Aβ42 peptide representing a major isoform in the senile plaques. Given the pathological significance of Aβ42 in the progression of AD, there is considerable interest in understanding the structural ensembles for soluble monomer and oligomeric forms of Aβ42.