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Writing is an essential part of a successful career in science. As such, many undergraduate science courses have begun to implement writing assignments that reflect "real-world" applications and focus on a critical analysis of current literature; these assignments are often in the form of a review or a research proposal. The semester-long project described herein is a unique marriage of these two ideas: students first select a topic and conduct a literature review, and then choose an area of that same topic to investigate further in a peer-reviewed grant proposal. A modified version of this project, which incorporates peer-reviewed oral presentations, is also discussed. This project is designed for an upper-level undergraduate course, typically having 15-20 students, and the approach (or parts of the approach) has been successfully incorporated in an advanced organic chemistry course, a biochemistry capstone course, and courses in endocrinology, as well as ecophysiology.

The deuterated form of iron oxyhydroxide goethite (alpha-FeOOD), one of the major inorganic components of soil, was studied by using the (super 2)H MAS NMR spectroscopy. The feasibility of applying NMR methods to characterize the local internal and surface structures of these classes of materials is demonstrated.

Summary Objectives: The overall aim of the project was for an advanced critical care practitioner (ACCP) to develop the clinical competency of arterial catheterisation. The study examined the impact of the intervention being performed by a different staff group member . Design: The project took the form of service development, employing a service redesign route-map. The general strategy was a pre/post implementation audit providing a baseline, to evaluate the change. Setting: The setting was an Adult General High Dependency Unit (HDU) in a large Teaching Hospital. Outcome measures: To reduce delay in arterial line insertion, whilst maintaining patient safety pre/post procedure, to a standard comparable to medical colleagues and to reduce the number of arterial punctures. Results: Insertion complications reduced by 9% (1), with no increase in infection. Post procedure complications increased by 18% (2); however this occurred during medical team insertions, with no increase in infection during ACCP line insertions. Observing the whole service, both medical and ACCP insertions, mean length of wait, reduced from 4.3 hours to 1.2 hours: compared to less than 45 minutes during ACCP insertions. The total number of arterial punctures for each patient, prior to receiving an arterial line, decreased to less than three stabs. Conclusion: All outcomes were achieved within ACCP practice, showing safe arterial line insertion by an ACCP in critically ill patients on HDU. Regular practice of the skill led to an improved technique and a reduction in delays. [ABSTRACT FROM AUTHOR]

Polysaccharide deacetylases are bacterial enzymes that catalyze the deacetylation of acetylated sugars on the membranes of Gram-positive bacteria, allowing them to be unrecognized by host immune systems. Inhibition of these enzymes would disrupt such pathogenic defensive mechanisms and therefore offers a promising route for the development of novel antibiotic therapeutics. Here, the first X-ray crystal structure of BA0150, a putative polysaccharide deacetylase from Bacillus anthracis, is reported to 2.0 Å resolution. The overall structure maintains the conserved (α/β)8 fold that is characteristic of this family of enzymes. The lack of a catalytic metal ion and a distinctive metal-binding site, however, suggest that this enzyme is not a functional polysaccharide deacetylase. [ABSTRACT FROM AUTHOR]

The first committed step of lipid A biosynthesis is catalyzed by UDP-(3-O-((R)-3-hydro-xymvristoyl))-N-acetylglucosamine deacetylase, a metal-dependent deacetylase also known as LpxC. Because lipid A is essential for bacterial viability, the inhibition of LpxC is an appealing therapeutic strategy for the treatment of Gram-negative bactertal infections. Here we report the 1.79 A resolution X-ray crystal structure of LpxC from Yersinia enterocolitica (YeLpxC) complexed with the potent hydroxamate inhibitor CHIR-090. This enzyme is a nearly identical orthologue of LpxC from Yersinia pestis (99.7% sequence identity), the pathogen that causes bubonic plague. Similar to the inhibition of LpxC from Escherichia coli. CHIR-090 inhibits YeLpxC via a two-step slow, tight-binding mechanism with an apparent Ki of 0.54 ± 0.14 nM followed by conversion of the E • I to E • I* species with a rate constant of 0.11 ± 0.01 mini-1. The structure of the LpxC complex with CHIR-090 shows that the inhibitor hydroxamate group chelates the active site zinc ion, and the "tail" of the inhibitor hinds in the hydrophobic tunnel in the active site. This hydrophobic tunnel is framed by a βαβ subdomain that exhibits significant conformational flexibility as it accommodates inhibitor binding. CHIR-090 displays a 27 mm zone of inhibition against Y. enterocolitica in a Kirby-Bauer antibiotic assay. which is comparable to its reported activity against other Gram-negative species including E. coli and Pseudomonas aeruginosa. This study demonstrates that the inhibition of LpxC should be explored as a potential therapeutic and/or prophylatic response to infection by weaponized Yersinia species. [ABSTRACT FROM AUTHOR]

Isotope-edited FT-IR spectroscopy is a combined synthetic and spectroscopic method used to characterize local (e.g., residue-level) vibrational environments of biomolecules. We have prepared the 3(10) helical peptide Z-Aib6-OtBu and seven (13)C-enriched analogues that vary only in the number and position(s) of (13)C═O isotopic enrichment. FT-IR spectra of these eight peptides solvated in the nonpolar aprotic solvent dichloromethane have been collected and compared to frequency, intensity, and normal mode results of DFT calculations. Single (13)C enrichment of amide functional groups tends to localize amide I vibrational eigenmodes, providing residue-specific information regarding the local environment (e.g., hydrogen bonding or solvent exposure) of the peptide bond. Double (13)C enrichment of Z-Aib6-OtBu allows for examination of interamide coupling between two labeled amide functional groups, providing experimental evidence of interamide coupling in the context of 3(10) helical structure. Although the calculated and observed interamide couplings of Z-Aib6-OtBu are a few cm(-1) and less, the eight peptides exhibit distinct infrared spectra, revealing details of interamide coupling and residue level vibrational environments.