Ultra-Efficient Solid-Phase Peptide Synthesis.

Microwave peptide synthesis offers significant advantages for peptide production in speed, efficiency, and overall purity. This chapter surveys key developments including the introduction of a wash-free methodology that has enabled 95% waste reduction in peptide synthesis at both research and production level solid-phase peptide synthesis (SPPS). Microwave SPPS is a widely used technique for R&D scale peptide synthesis with more recent expansion into larger scale current good manufacturing practice (cGMP).

Sequence-activity mapping via depletion reveals striking mutational tolerance and elucidates functional motifs in Tur1a antimicrobial peptide.

Proline-rich antimicrobial peptides (PrAMPs) are attractive antibiotic candidates that target gram-negative bacteria ribosomes. We elucidated the sequence-function landscape of 43 000 variants of a recently discovered family member, Tur1a, using the validated SAMP-Dep platform that measures intracellular AMP potency in a high-throughput manner via self-depletion of the cellular host. The platform exhibited high replicate reproducibility (ρ = 0.

Sequence-function mapping of proline-rich antimicrobial peptides.

Antimicrobial peptides (AMPs) are essential elements of natural cellular combat and candidates as antibiotic therapy. Elevated function may be needed for robust physiological performance. Yet, both pure protein design and combinatorial library discovery are hindered by the complexity of antimicrobial activity.

Total wash elimination for solid phase peptide synthesis.

We present a process for solid phase peptide synthesis (SPPS) that completely eliminates all solvent intensive washing steps during each amino acid addition cycle. A key breakthrough is the removal of a volatile Fmoc deprotection base through bulk evaporation at elevated temperature while preventing condensation on the vessel surfaces with a directed headspace gas flushing. This process was demonstrated at both research and production scales without any impact on product quality and when applied to a variety of challenging sequences (up to 89 amino acids in length).

Exercise capacity following SARS-CoV-2 infection is related to changes in cardiovascular and lung function in military personnel.

Background: Since the COVID-19 pandemic, post-COVID syndrome (persistent symptoms/complications lasting >12 weeks) continues to pose medical and economic challenges. In military personnel, where optimal fitness is crucial, prolonged limitations affecting their ability to perform duties has occupational and psychological implications, impacting deployability and retention. Research investigating post-COVID syndrome exercise capacity and cardiopulmonary effects in military personnel is limited.

Mobilising Extremism in Times of Change: Analysing the UK's Far-Right Online Content During the Pandemic.

The growing dissension towards the political handling of COVID-19, widespread job losses, backlash to extended lockdowns, and hesitancy surrounding the vaccine are propagating toxic far-right discourses in the UK. Moreover, the public is increasingly reliant on different social media platforms, including a growing number of participants on the far-right's fringe online networks, for all pandemic-related news and interactions. Therefore, with the proliferation of harmful far-right narratives and the public's reliance on these platforms for socialising, the pandemic environment is a breeding ground for radical ideologically-based mobilisation and social fragmentation.

The Politics of Re-Opening Schools: Explaining Public Preferences Reopening Schools and Public Compliance with Reopening Orders During the COVID-19 Pandemic.

Due to the COVID-19 Pandemic, the decision to reopen schools for in-person instruction has become a pressing policy issue. This study examines what overall factors drive public support for schools re-opening in person and whether members of the public are willing to comply with school re-opening decisions based on their own preferences and/or the level of government from which the order comes. Through two rounds of national surveys with an embedded experiment, I find consistent evidence that 1) trust in information from elites - not contact with COVID - best explain preferences for reopening, 2) political ideology and racial and class identification help explain preferences as well, and 3) the President of the United States is best positioned to generate compliance with a school reopening mandate.

Altered lung physiology in two cohorts after COVID-19 infection as assessed by computed cardiopulmonography.

The longer-term effects of COVID-19 on lung physiology remain poorly understood. Here, a new technique, computed cardiopulmonography (CCP), was used to study two COVID-19 cohorts (MCOVID and C-MORE-LP) at both ∼6 and ∼12 mo after infection. CCP is comprised of two components.

Quantitative 1H-NMR analysis reveals steric and electronic effects on the substrate specificity of benzoate dioxygenase in Ralstonia eutropha B9.

The cis-dihydroxylation of arenes by Rieske dearomatizing dioxygenases (RDDs) represents a powerful tool for the production of chiral precursors in organic synthesis. Here, the substrate specificity of the RDD benzoate dioxygenase (BZDO) in Ralstonia eutropha B9 whole cells was explored using quantitative 1H nuclear magnetic resonance spectroscopy (q1H-NMR). The specific activity, specific carbon uptake, and regioselectivity of the dihydroxylation reaction were evaluated in resting cell cultures for a panel of 17 monosubstituted benzoates.

New Developments in Microwave-Assisted Solid Phase Peptide Synthesis.

The unique combination of microwave heating with optimized carbodiimide activation has proven to be an indispensable technique for high-throughput peptide production. Here, we describe new methods in microwave-assisted solid phase peptide synthesis and optimized post-synthesis modifications that have been recently developed. These methods have drastically reduced synthesis time and solvent requirement while delivering peptides in high crude purities.

Ultra-protective mechanical ventilation without extra-corporeal carbon dioxide removal for acute respiratory distress syndrome.

Background: Tidal hyperinflation can still occur with mechanical ventilation using low tidal volume (LVT) (6 mL/kg predicted body weight (PBW)) in acute respiratory distress syndrome (ARDS), despite a well-demonstrated reduction in mortality.

Methods: Retrospective chart review from August 2012 to October 2014. : Age >18years, PaO/FiO<200 with bilateral pulmonary infiltrates, absent heart failure, and ultra-protective mechanical ventilation (UPMV) defined as tidal volume (VT) <6 mL/kg PBW.

Corrigendum: Cancer Cell Mitochondria Targeting by Pancratistatin Analogs is Dependent on Functional Complex II and III.

This corrects the article DOI: 10.1038/srep42957.

Process boundaries of irreversible scCO2 -assisted phase separation in biphasic whole-cell biocatalysis.

The formation of stable emulsions in biphasic biotransformations catalyzed by microbial cells turned out to be a major hurdle for industrial implementation. Recently, a cost-effective and efficient downstream processing approach, using supercritical carbon dioxide (scCO2 ) for both irreversible emulsion destabilization (enabling complete phase separation within minutes of emulsion treatment) and product purification via extraction has been proposed by Brandenbusch et al. (2010).

The dynamic influence of cells on the formation of stable emulsions in organic-aqueous biotransformations.

Emulsion stability plays a crucial role for mass transfer and downstream processing in organic-aqueous bioprocesses based on whole microbial cells. In this study, emulsion stability dynamics and the factors determining them during two-liquid phase biotransformation were investigated for stereoselective styrene epoxidation catalyzed by recombinant Escherichia coli. Upon organic phase addition, emulsion stability rapidly increased correlating with a loss of solubilized protein from the aqueous cultivation broth and the emergence of a hydrophobic cell fraction associated with the organic-aqueous interface.

High-efficiency solid phase peptide synthesis (HE-SPPS).

A series of improvements to the standard solid phase peptide synthesis (SPPS) process allowing for significant gains in product purity along with only a 4 min standard cycle time and a 90% reduction in total waste produced is reported. For example, syntheses of the well-known (65-74)acyl carrier protein (ACP) and (1-42)β-amyloid peptides were accomplished with 93 and 72% purity (UPLC-MS) in only 44 and 229 min, respectively.

Fire promotes pollinator visitation: implications for ameliorating declines of pollination services.

Pollinators serve critical roles for the functioning of terrestrial ecosystems, and have an estimated annual value of over $150 billion for global agriculture. Mounting evidence from agricultural systems reveals that pollinators are declining in many regions of the world, and with a lack of information on whether pollinator communities in natural systems are following similar trends, identifying factors which support pollinator visitation and services are important for ameliorating the effects of the current global pollinator crisis. We investigated how fire affects resource structure and how that variation influences floral pollinator communities by comparing burn versus control treatments in a southeastern USA old-field system.

Enhancement of apoptotic and autophagic induction by a novel synthetic C-1 analogue of 7-deoxypancratistatin in human breast adenocarcinoma and neuroblastoma cells with tamoxifen.

Breast cancer is one of the most common cancers amongst women in North America. Many current anti-cancer treatments, including ionizing radiation, induce apoptosis via DNA damage. Unfortunately, such treatments are non-selective to cancer cells and produce similar toxicity in normal cells.

Integrated organic-aqueous biocatalysis and product recovery for quinaldine hydroxylation catalyzed by living recombinant Pseudomonas putida.

In an earlier study, biocatalytic carbon oxyfunctionalization with water serving as oxygen donor, e.g., the bioconversion of quinaldine to 4-hydroxyquinaldine, was successfully achieved using resting cells of recombinant Pseudomonas putida, containing the molybdenum-enzyme quinaldine 4-oxidase, in a two-liquid phase (2LP) system (Ütkür et al.

Selective cytotoxicity against human osteosarcoma cells by a novel synthetic C-1 analogue of 7-deoxypancratistatin is potentiated by curcumin.

The natural compound pancratistatin (PST) is a non-genotoxic inducer of apoptosis in a variety of cancers. It exhibits cancer selectivity as non-cancerous cells are markedly less sensitive to PST. Nonetheless, PST is not readily synthesized and is present in very low quantities in its natural source to be applied clinically.

A novel synthetic C-1 analogue of 7-deoxypancratistatin induces apoptosis in p53 positive and negative human colorectal cancer cells by targeting the mitochondria: enhancement of activity by tamoxifen.

The natural compound pancratistatin (PST), isolated from the Hymenocallis littoralis plant, specifically induces apoptosis in many cancer cell lines. Unlike many other chemotherapeutics, PST is not genotoxic and has minimal adverse effects on non-cancerous cells. However, its availability for preclinical and clinical work is limited due to its low availability in its natural source and difficulties in its chemical synthesis.

Chemoenzymatic synthesis of Amaryllidaceae constituents and biological evaluation of their C-1 analogues. The next generation synthesis of 7-deoxypancratistatin and trans-dihydrolycoricidine.

An efficient synthesis of C-1 derivatives of 7-deoxypancratistatin is reported. The key steps include the following: selective opening of an epoxide with aluminum acetylide in the presence of an aziridine; solid-state silica-gel-catalyzed opening of an aziridine; and oxidative cleavage of a phenanthrene core and its recyclization to phenanthridone to provide the key C-1 aldehyde 22. The conversion of this aldehyde to C-1 acetoxymethyl and C-1 hydroxymethyl derivatives is described along with the evaluation of their biological activity against several cancer cell lines and in an apoptosis study.

Investigation of steric and functionality limits in the enzymatic dihydroxylation of benzoate esters. Versatile intermediates for the synthesis of pseudo-sugars, amino cyclitols, and bicyclic ring systems.

A series of benzoate esters (methyl, ethyl, n-Pr, i-Pr, n-Bu, t-Bu, allyl, and propargyl) were subjected to enzymatic dihydroxylation by E. coli JM 109(pDTG 601) strain in a whole-cell fermentation. The cis-cyclohexadienediols were obtained in yields of approximately 1g/L except for n-propyl- and i-propyl benzoate which were found to be poor substrates.

A cryptic diagnosis: disseminated cryptococcal disease presenting as an asymptomatic pulmonary nodule and a skin lesion: a case report.

Background: Cryptococcosis refers to a spectrum of infections caused by the encapsulated yeast Cryptococcus neoformans. In the immunocompromised host cryptococcus may disseminate resulting in significant mortality and morbidity.

Case Presentation: We report the case of a 49-year-old homosexual male presenting with an atypical skin lesion associated with an asymptomatic pulmonary nodule.