The profound stability of bacterial spores makes them a promising platform for biotechnological applications like biocatalysis, bioremediation, drug delivery, etc. However, though the spore is composed of >40 proteins, only ∼12 have been explored as fusion carriers for protein display. Here, we assessed the suitability of 33 spore proteins (SPs) as enzyme display carriers by direct allele tagging at native genomic loci.
View Article and Find Full Text PDFMicrobial-derived natural products remain a major source of structurally diverse bioactive compounds and chemical scaffolds that have the potential as new therapeutics to target drug-resistant pathogens and cancers. In particular, genome mining has revealed the vast number of cryptic or low-yield biosynthetic gene clusters in the genus Streptomyces. However, low natural product yields-improvements to which have been hindered by the lack of high throughput methods-have slowed the discovery and development of many potential therapeutics.
View Article and Find Full Text PDFMicrobial derived natural products remain a major source of structurally diverse bioactive compounds and chemical scaffolds that have potential as new therapeutics to target drug resistant pathogens and cancers. In particular, genome mining has revealed the vast number of cryptic or low yield biosynthetic gene clusters in the genus . Here, we describe our efforts to improve yields of landomycins - angucycline family polyketides under investigation as cancer therapeutics - by a genetically modified 136.
View Article and Find Full Text PDFEngineering the utilization of non-native substrates, or synthetic heterotrophy, in proven industrial microbes such as Saccharomyces cerevisiae represents an opportunity to valorize plentiful and renewable sources of carbon and energy as inputs to bioprocesses. We previously demonstrated that activation of the galactose (GAL) regulon, a regulatory structure used by this yeast to coordinate substrate utilization with biomass formation during growth on galactose, during growth on the non-native substrate xylose results in a vastly altered gene expression profile and faster growth compared with constitutive overexpression of the same heterologous catabolic pathway. However, this effort involved the creation of a xylose-inducible variant of Gal3p (Gal3p), the sensor protein of the GAL regulon, preventing this semi-synthetic regulon approach from being easily adapted to additional non-native substrates.
View Article and Find Full Text PDFA strategy has been developed for the carbon-14 radiosynthesis of [ C]-SHP-141, a 4-(7-hydroxycarbamoyl-heptanoyloxy)-benzoic acid methyl ester derivative containing a terminal hydroxamic acid. The synthesis involved four radiochemical transformations. The key step in the radiosynthesis was the conversion of the 7-[ C]-cyano-heptanoic acid benzyloxyamide [ C]-4 directly into the carboxylic acid derivative, 7-benzyloxycarbamoyl-[ C]-heptanoic acid [ C]-8 using nitrilase-113 biocatalyst.
View Article and Find Full Text PDFDeep mutational scanning (DMS) has recently emerged as a powerful method to study protein sequence-function relationships but it has not been well-explored as a guide to enzyme engineering and identifying pathways by which their catalytic cycle may be improved. We report such a demonstration in this work using a Phenylalanine ammonia-lyase (PAL), which deaminates L-phenylalanine to -cinnamic acid and has widespread application in chemo-enzymatic synthesis, agriculture, and medicine. In particular, the PAL from (AvPAL*) has garnered significant attention as the active ingredient in Pegvaliase, the only FDA-approved drug treating classical Phenylketonuria (PKU).
View Article and Find Full Text PDFTranscription factor (TF)-based biosensors are very desirable reagents for high-throughput enzyme and strain engineering campaigns. Despite their potential, they are often difficult to deploy effectively as the small molecules being detected can leak out of high-producer cells, into low-producer cells, and activate the biosensor therein. This crosstalk leads to the overrepresentation of false-positive/cheater cells in the enriched population.
View Article and Find Full Text PDFBackground: Current treatment of vulvovaginal candidiasis (VVC) is largely limited to azole therapy. Ibrexafungerp is a first-in-class triterpenoid antifungal with broad-spectrum anti-Candida fungicidal activity. The objective of this study was to evaluate the efficacy and safety of ibrexafungerp compared with placebo in patients with acute VVC.
View Article and Find Full Text PDFAm J Obstet Gynecol
August 2021
Background: According to the Centers for Disease Control and Prevention, rates of infection for Chlamydia trachomatis and Neisseria gonorrhoeae are increasing in the United States. EVO100 is an investigational antimicrobial, pH-modulating, vaginal gel with active ingredients L-lactic acid, citric acid, and potassium bitartrate that is being evaluated for the prevention of sexually transmitted infections.
Objective: The objective of this phase 2B/3 study was to assess the efficacy and safety of EVO100 for the prevention of chlamydia and gonorrhea.
NPJ Biofilms Microbiomes
October 2020
Biofilms are an emerging target for new therapeutics in the effort to address the continued increase in resistance and tolerance to traditional antimicrobials. In particular, the distinct nature of the biofilm growth state often means that traditional antimcirobials, developed to combat planktonic cells, are ineffective. Biofilm treatments are designed to both reduce pathogen load at an infection site and decrease the development of resistance by rendering the embedded organisms more susceptible to treatment at lower antimicrobial concentrations.
View Article and Find Full Text PDFObjective: The objective was to evaluate the contraceptive effectiveness, safety, and acceptability of a novel vaginal pH regulator over seven cycles of use.
Study Design: A single-arm, open-label, phase 3 study was conducted across 112 sites in the United States in sexually active 18-35-year-old women at risk of pregnancy. Women administered the study treatment ≤ 1 h before each episode of intercourse.
There is broad interest in engineering phenylalanine ammonia-lyase (PAL) for its biocatalytic applications in industry and medicine. While site-specific mutagenesis has been employed to improve PAL stability or substrate specificity, combinatorial techniques are poorly explored. Here, we report development of a directed evolution technique to engineer PAL enzymes.
View Article and Find Full Text PDFMucus in the gastrointestinal (GI) tract is the primary point-of-interaction between humans and their gut microbiota. This intimates that mucus not only ensures protection against endogenous and exogenous opportunists but also provisions for the human microbiota to reside and flourish. With the emergence of living therapeutics, engineered microbes can deliver and produce increasingly complex medicine, and controlling the mucoadhesive properties of different microbial chassis can dictate dose-response in a patient.
View Article and Find Full Text PDFBackground: Limb length discrepancy (LLD) in the setting of concurrent hindfoot and ankle deformity poses an added level of complexity to the reconstructive surgeon. Regardless of etiology, a clinically significant LLD poses additional challenges without a forthright and validated solution. The purpose of the current study is to determine whether reconstructive hindfoot and ankle surgery with concurrent lengthening through a distal tibial corticotomy is comparable to other treatment alternatives in the literature.
View Article and Find Full Text PDFBiotechnol Bioeng
October 2017
Escherichia coli is an important commercial species used for production of biofuels, biopolymers, organic acids, sugar alcohols, and natural compounds. Processed biomass and agroindustrial byproducts serve as low-cost nutrient sources and contain a variety of hexoses available for bioconversion. However, metabolism of hexose mixtures by E.
View Article and Find Full Text PDFDiabetic Charcot neuroarthropathy is a complex, limb-threatening disease process with major lifestyle-altering repercussions for patients. When Charcot neuroarthropathy leads to unstable deformity, ulceration, and potential infection despite conservative therapies, foot and ankle surgeons often consider reconstructive limb salvage procedures to restore function. The purpose of the present study was to evaluate the clinical and radiographic outcomes of diabetic Charcot reconstruction using combined internal and external fixation.
View Article and Find Full Text PDFBackground: There is heterogeneity in the literature regarding the anatomy and number of ligamentous bands that form the deltoid ligament (DL). Anatomic knowledge of the DL and its variations are important for surgeons who repair ankle fractures.
Methods: The DL was dissected in 33 ankles from 17 formalin-fixed cadavers (mean age at death, 76.
There is no consensus in the literature related to the morphology, bony attachments, and variations of the fibular collateral ligament (FCL) of the knee. Our purpose was to investigate FCL morphology and to review reports in the literature regarding this structure. Seventy knees from formalin-fixed, adult cadavers were dissected and a digital caliper was used to measure FCL length, width, distance from proximal attachment to articular surface (PA→AS), and distance from distal attachment to articular surface (DA→AS).
View Article and Find Full Text PDFBackground: Many cadaver-based anatomy courses and surgical workshops use prosections to help podiatry students and residents learn clinically relevant anatomy. The quality of these prosections is variable and dependent upon the methods used to prepare them. These methods have not been adequately described in the literature, and few studies describe the use of chemicals to prepare prosections of the cadaveric foot and ankle.
View Article and Find Full Text PDF