Peptide-Modified Gemini Surfactants as Delivery System Building Blocks with Dual Functionalities for Glaucoma Treatment: Gene Carriers and Amyloid-Beta (Aß) Self-Aggregation Inhibitors.

Retinal ganglion cell (RGC) neurodegeneration in glaucoma has potential links with amyloid-ß (Aß) deposition. Targeting the Aß pathway was shown to reduce RGC apoptosis and protect RGCs from degeneration. We report exploratory studies on the amyloid Aß40 aggregation inhibition properties of four cell adhesion peptide (CAP)-gemini surfactants that are intended as building blocks for gene carrier nanoparticles for glaucoma treatment. The CAP-gemini surfactants (18-7N(p1-4)-18) were evaluated as potential Aß40 peptide aggregation inhibitors by a fluorescence kinetic assay and for their binding interactions with Aß40 dimers by molecular docking studies. In vitro Aß40 peptide aggregation inhibition studies showed that the 18-7N(p3)-18 and 18-7N(p1)-18 ligands inhibit Aß40 peptide aggregation and prevent the formation of higher order structures. CDOCKER energies and CDOCKER interaction energies demonstrated that the CAP-gemini surfactants formed more stable complexes in the Aß40 dimer assembly and underwent both polar and nonpolar interactions compared to CAP peptides alone. Also, 18-7N(p3)-18 showed a significantly lower CDOCKER energy compared to that of the unmodified gemini surfactant 18-7NH-18 (p < 0.0001) and 18-7N(p4)-18 (p < 0.001), 18-7N(p1)-18, and 18-7N(p2)-18. Similarly, 18-7N(p3)-18 showed a significantly lower CDOCKER interaction energy compared to that of 18-7NH-18, 18-7N(p4)-18 (p < 0.0001), and 18-7N(p2)-18 (p < 0.001), while 18-7N(p3)-18 and 18-7N(p1)-18 showed similar CDOCKER interaction energies. These studies suggest that a combination of both hydrophobic and electrostatic interactions contributes to the anti-Aß40 aggregation activity of CAP-gemini surfactants. CAP-gemini surfactants showed 10-fold better Aß40 peptide aggregation inhibition compared to previously reported values and could provide a new opportunity for glaucoma treatment as dual-functional gene carriers.

Anti-LPS IgA and IgG Can Inhibit Serum Killing of Pseudomonas aeruginosa in Patients with Cystic Fibrosis.

Pseudomonas aeruginosa is one of the principal pathogens implicated in respiratory infections of patients with cystic fibrosis (CF) and non-CF bronchiectasis. Previously, we demonstrated that impaired serum-mediated killing of P. aeruginosa was associated with increased severity of respiratory infections in patients with non-CF bronchiectasis. This inhibition was mediated by high titers of O-antigen-specific IgG2 antibodies that cloak the surface of the bacteria, blocking access to the membrane. Infection-related symptomatology was ameliorated in patients by using plasmapheresis to remove the offending antibodies. To determine if these inhibitory "cloaking antibodies" were prevalent in patients with CF, we investigated 70 serum samples from patients with P. aeruginosa infection and 5 from those without P. aeruginosa infection. Of these patients, 32% had serum that inhibited the ability of healthy control serum to kill P. aeruginosa. Here, we demonstrate that this inhibition of killing requires O-antigen expression. Furthermore, we reveal that while IgG alone can inhibit the activity of healthy control serum, O-antigen-specific IgA in patient sera can also inhibit serum-killing. We found that antibody affinity, not just titer, was also important in the inhibition of serum-mediated killing. These studies provide novel insight into cloaking antibodies in human infection and may provide further options in CF and other diseases for treatment of recalcitrant P. aeruginosa infections.

Interactions of polyunsaturated fatty acids with amyloid peptides Aß40 and Aß42.

Polyunsaturated fatty acids (PUFAs) are reported to exert beneficial effects in Alzheimer's disease. Some PUFAs are known to reduce amyloid-beta (Aß) toxicity by promoting its degradation and clearance. Studies on the direct interactions of PUFAs with Aß peptides are limited and contradictory. In this study, we report the interactions of fatty acids docosahexaenoic acid (DHA), eicosatetraenoic acid (EPA), α-linolenic acid (ALA), arachidonic acid (ARA), linoleic acid (LNA) and oleic acid (OA) with Aß peptides by carrying out fluorescence based aggregation kinetic experiments, transmission electron microscopy and molecular docking studies. Our investigations demonstrate that all the fatty acids tested exhibit anti-aggregation properties by preventing both Aß40 and Aß42 fibrillogenesis (∼16-84% inhibition). OA and DHA were identified as excellent inhibitors of Aß40 or Aß42 fibrillogenesis respectively (∼84% and 81% inhibition at 25 µM). Molecular docking studies conducted, using the dimer and oligomer models of Aß40 peptide, suggest that these fatty acids interact in the aggregation prone Phe19-Ala21 and the ß-turn region (Asp23-Lys28) whereas a similar study with Aß42 dimer and oligomer models, indicate that the fatty acids were oriented in a hydrophobic region (Gln15, Leu16, Leu17 and Leu34). These results, suggest that DHA, EPA, ALA, ARA, LNA and OA are capable of directly interacting with both Aß40 and Aß42 peptides. These studies will have implications in developing potential therapeutics for Alzheimer's disease.

The effects of heat and freeze-thaw cycling on naloxone stability.

PURPOSE: The availability of take home naloxone (THN) was increased for Canadians in 2016, including access to kits via pharmacies. Unlike typical over-the-counter (OTC) and prescription drugs, THN kits may be stored in non-standard conditions, including in vehicles, backpacks, and out of doors. To evaluate whether these non-standard storage conditions affect stability, we investigated the impact of heat and freeze-thaw cycling on naloxone hydrochloride stability. METHODS: To assess the effect of heat, naloxone hydrochloride ampoules were exposed to 80 °C in a temperature-controlled oven for 8 h followed by 16 h at room temperature. To assess the effect of freeze-thaw cycles, naloxone hydrochloride ampoules were exposed to - 20 °C for 16 h followed by 8 h at 4 °C. The impact of these conditions on naloxone hydrochloride stability was evaluated each day for 1 week and after 2 and 4 weeks. The concentration of remaining naloxone hydrochloride was quantified using high-performance liquid chromatography (HPLC). Naloxone hydrochloride ampoules stored at room temperature served as the experimental control. RESULTS: Naloxone hydrochloride ampoules exhibit no changes in drug concentration following exposure to heat or freeze-thaw cycles for up to 28 days compared to ampoules maintained at room temperature (as indicated in the product monograph). CONCLUSIONS: Naloxone hydrochloride remains chemically stable following exposure to heat or freeze-thaw cycles after 28 days. If THN kits are stored in non-standard conditions (for up to 28 days) the active naloxone is likely to remain stable. Despite this, pharmacists should continue to emphasize the importance of appropriate storage of THN kits to ensure optimal efficacy should naloxone administration be required in an emergency situation.

Quinolines from the cyclocondensation of isatoic anhydride with ethyl acetoacetate: preparation of ethyl 4-hydroxy-2-methylquinoline-3-carboxylate and derivatives.

A convenient two-step synthesis of ethyl 4-hydroxy-2-methylquinoline-3-carboxylate derivatives has been developed starting from commercially available 2-aminobenzoic acids. In step 1, the anthranilic acids are smoothly converted to isatoic anhydrides using solid triphosgene in THF. In step 2, the anhydride electrophiles are reacted with the sodium enolate of ethyl acetoacetate, generated from sodium hydroxide, in warm N,N-dimethylacetamide resulting in the formation of substituted quinolines. A degradation-build-up strategy of the ethyl ester at the 3-position allowed for the construction of the α-hydroxyacetic acid residue required for the synthesis of key arylquinolines involved in an HIV integrase project.

Low- and High-Grade Glioma-Associated Vascular Cells Differentially Regulate Tumor Growth.

A key feature distinguishing high-grade glioma (HG) from low-grade glioma (LG) is the extensive neovascularization and endothelial hyperproliferation. Prior work has shown that tumor-associated vasculature from HG is molecularly and functionally distinct from normal brain vasculature and expresses higher levels of protumorigenic factors that promote glioma growth and progression. However, it remains unclear whether vessels from LG also express protumorigenic factors, and to what extent they functionally contribute to glioma growth. Here, we profile the transcriptomes of glioma-associated vascular cells (GVC) from IDH-mutant (mIDH) LG and IDH-wild-type (wIDH) HG and show that they exhibit significant molecular and functional differences. LG-GVC show enrichment of extracellular matrix-related gene sets and sensitivity to antiangiogenic drugs, whereas HG-GVC display an increase in immune response-related gene sets and antiangiogenic resistance. Strikingly, conditioned media from LG-GVC inhibits the growth of wIDH glioblastoma cells, whereas HG-GVC promotes growth. In vivo cotransplantation of LG-GVC with tumor cells reduces growth, whereas HG-GVC enhances tumor growth in orthotopic xenografts. We identify ASPORIN (ASPN), a small leucine-rich repeat proteoglycan, highly enriched in LG-GVC as a growth suppressor of wIDH glioblastoma cells in vitro and in vivo. Together, these findings indicate that GVC from LG and HG are molecularly and functionally distinct and differentially regulate tumor growth. Implications: This study demonstrated that vascular cells from IDH-mutant LG and IDH-wild-type HG exhibit distinct molecular signatures and have differential effects on tumor growth via regulation of ASPN-TGFß1-GPM6A signaling.

Genomic analyses of Burkholderia respiratory isolates indicates two evolutionarily distinct B. anthina clades.

Introduction: The Burkholderia cepacia complex (BCC) encompasses a group of at least 22 genetically distinct gram-negatives bacterial species ubiquitous in nature. Recognised as a group of genetically and phenotypically flexible species, the BCC inhabits diverse ecological niches causing both plant and human diseases. Comparative genomic analysis provides an in depth understanding into the population biology, phylogenetic relationship, and genomic architecture of species. Methods: Here, we genomically characterise Burkholderia anthina isolated from patients with chronic lung infections, an understudied pathogen within the Burkholderia cepacia complex. Results: We demonstrate that B. anthina is polyphyletic and constitutes two distinct evolutionary lineages. Core- and pan-genome analyses demonstrated substantial metabolic diversity, with B. anthina Clade I enriched in genes associated with microbial metabolism in diverse environments, including degradation of aromatic compounds and metabolism of xenobiotics, while B. anthina Clade II demonstrated an enhanced capability for siderophore biosynthesis. Discussion: Based on our phylogenetic and comparative genomic analyses, we suggest stratifying B. anthina to recognise a distinct species harbouring increased potential for iron metabolism via siderophore synthesis, for which we propose the name Burkholderia anthinoferum (sp. nov.).

Low- and high-grade glioma endothelial cells differentially regulate tumor growth.

Background: A key feature distinguishing high-grade glioma (HGG) from low-grade glioma (LGG) is the extensive neovascularization and endothelial hyperproliferation. Prior work has shown that tumor endothelial cells (TEC) from HGG are molecularly and functionally distinct from normal brain EC and secrete higher levels of pro-tumorigenic factors that promote glioma growth and progression. However, it remains unclear whether TEC from LGG also express pro-tumorigenic factors, and to what extent they functionally contribute to glioma growth. Methods: Transcriptomic profiling was conducted on tumor endothelial cells (TEC) from grade II/III (LGG, IDH-mutant) and grade IV HGG (IDH-wildtype). Functional differences between LGG- and HGG-TEC were evaluated using growth assays, resistance to anti-angiogenic drugs and radiation therapy. Conditioned media and specific factors from LGG- and HGG-TEC were tested on patient-derived gliomasphere lines using growth assays in vitro and in co-transplantation studies in vivo in orthotopic xenograft models. Results: LGG-TEC showed enrichment of extracellular matrix and cell cycle-related gene sets and sensitivity to anti-angiogenic therapy whereas HGG-TEC displayed an increase in immune response-related gene sets and anti-angiogenic resistance. LGG- and HGG-TEC displayed opposing effects on growth and proliferation of IDH-wildtype and mutant tumor cells. Asporin (ASPN), a small leucine rich proteoglycan enriched in LGG-TEC was identified as a growth suppressor of IDH-wildtype GBM by modulating TGFΒ1-GPM6A signaling. Conclusions: Our findings indicate that TEC from LGG and HGG are molecularly and functionally heterogeneous and differentially regulate the growth of IDH-wildtype and mutant tumors.

Genomic diversity and antimicrobial resistance of Prevotella species isolated from chronic lung disease airways.

Cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) are characterized by increasingly frequent acute pulmonary exacerbations that reduce life quality and length. Human airways are home to a rich polymicrobial environment, which includes members of the obligately anaerobic genus Prevotella. Despite their commonness, surprisingly little is known about the prevalence, role, genomic diversity and antimicrobial resistance (AMR) potential of Prevotella species and strains in healthy and diseased airways. Here, we used comparative genomics to develop a real-time PCR assay to permit rapid Prevotella species identification and quantification from cultures and clinical specimens. Assay specificity was validated across a panel of Prevotella and non-Prevotella species, followed by PCR screening of CF and COPD respiratory-derived cultures. Next, 35 PCR-positive isolates were subjected to whole-genome sequencing. Of eight identified Prevotella species, P. histicola, P. melaninogenica, P. nanceiensis, P. salivae and P. denticola overlapped between participant cohorts. Phylogenomic analysis revealed considerable interhost but limited intrahost diversity, suggesting patient-specific lineages in the lower airways, probably from oral cavity aspirations. Correlation of phenotypic AMR profiles with AMR genes identified excellent correlation between tetQ presence and decreased doxycycline susceptibility, and ermF presence and decreased azithromycin susceptibility and clindamycin resistance. AMR rates were higher in the CF isolates, reflecting greater antibiotic use in this cohort. All tested Prevotella isolates were tobramycin-resistant, providing a potential selection method to improve Prevotella culture retrieval rates. Our addition of 35 airway-derived Prevotella genomes to public databases will enhance ongoing efforts to unravel the role of this diverse and enigmatic genus in both diseased and healthy lungs.

P300 promotes tumor recurrence by regulating radiation-induced conversion of glioma stem cells to vascular-like cells.

Glioma stem cells (GSC) exhibit plasticity in response to environmental and therapeutic stress leading to tumor recurrence, but the underlying mechanisms remain largely unknown. Here, we employ single-cell and whole transcriptomic analyses to uncover that radiation induces a dynamic shift in functional states of glioma cells allowing for acquisition of vascular endothelial-like and pericyte-like cell phenotypes. These vascular-like cells provide trophic support to promote proliferation of tumor cells, and their selective depletion results in reduced tumor growth post-treatment in vivo. Mechanistically, the acquisition of vascular-like phenotype is driven by increased chromatin accessibility and H3K27 acetylation in specific vascular genes allowing for their increased expression post-treatment. Blocking P300 histone acetyltransferase activity reverses the epigenetic changes induced by radiation and inhibits the adaptive conversion of GSC into vascular-like cells and tumor growth. Our findings highlight a role for P300 in radiation-induced stress response, suggesting a therapeutic approach to prevent glioma recurrence.

Drug Repurposing: Dipeptidyl Peptidase IV (DPP4) Inhibitors as Potential Agents to Treat SARS-CoV-2 (2019-nCoV) Infection.

The current outbreak of severe acute respiratory distress syndrome (SARS) or nCOVID-19 pandemic, caused by the coronavirus-2 (CoV-2), continues to wreak havoc globally. As novel vaccines are being discovered and developed, small molecule drugs still constitute a viable treatment option for SARS-CoV-2 infections due to their advantages such as superior patient compliance for oral therapies, reduced manufacturing costs and ease of large scale distribution due to better stability and storage profiles. Discovering new drugs for SARS-CoV-2 infections is a time consuming and expensive proposition. In this regard, drug repurposing is an appealing approach which can provide rapid access to therapeutics with proven record of safety and efficacy. We investigated the drug repurposing potential of a library of dipeptidyl peptidase 4 (DPP4) inhibitors which are currently marketed for type-2 diabetes as treatment option for SARS-CoV-2 infections. These computational studies led to the identification of three marketed DPP4 inhibitors; gemigliptin, linagliptin and evogliptin as potential inhibitors of SARS-CoV-2 Mpro viral cysteine protease. In addition, our computational modeling shows that these drugs have the potential to inhibit other viral cysteine proteases from the beta coronavirus family, including the SAR-CoV Mpro and MERS-CoV CLpro suggesting their potential to be repurposed as broad-spectrum antiviral agents.

Inferior outcomes in lung transplant recipients with serum Pseudomonas aeruginosa specific cloaking antibodies.

BACKGROUND: Chronic Lung Allograft Dysfunction (CLAD) limits long-term survival following lung transplantation. Colonization of the allograft by Pseudomonas aeruginosa is associated with an increased risk of CLAD and inferior overall survival. Recent experimental data suggests that 'cloaking' antibodies targeting the O-antigen of the P. aeruginosa lipopolysaccharide cell wall (cAbs) attenuate complement-mediated bacteriolysis in suppurative lung disease. METHODS: In this retrospective cohort analysis of 123 lung transplant recipients, we evaluated the prevalence, risk factors and clinical impact of serum cAbs following transplantation. RESULTS: cAbs were detected in the sera of 40.7% of lung transplant recipients. Cystic fibrosis and younger age were associated with increased risk of serum cAbs (CF diagnosis, OR 6.62, 95% CI 2.83-15.46, p < .001; age at transplant, OR 0.69, 95% CI 0.59-0.81, p < .001). Serum cAbs and CMV mismatch were both independently associated with increased risk of CLAD (cAb, HR 4.34, 95% CI 1.91-9.83, p < .001; CMV mismatch (D+/R-), HR 5.40, 95% CI 2.36-12.32, p < .001) and all-cause mortality (cAb, HR 2.75, 95% CI 1.27-5.95, p = .010, CMV mismatch, HR 3.53, 95% CI 1.62-7.70, p = .002) in multivariable regression analyses. CONCLUSIONS: Taken together, these findings suggest a potential role for 'cloaking' antibodies targeting P. aeruginosa LPS O-antigen in the immunopathogenesis of CLAD.

Therapeutic opportunities in cancer therapy: targeting the p53-MDM2/MDMX interactions.

Ubiquitination is a key enzymatic post-translational modification that influences p53 stability and function. p53 protein regulates the expression of MDM2 (mouse double-minute 2 protein) E3 ligase and MDMX (double-minute 4 protein), through proteasome-based degradation. Exploration of targeting the ubiquitination pathway offers a potentially promising strategy for precision therapy in a variety of cancers. The p53-MDM2-MDMX pathway provides multiple molecular targets for small molecule screening as potential therapies for wild-type p53. As a result of its effect on molecular carcinogenesis, a personalized therapeutic approach based on the wild-type and mutant p53 protein is desirable. We highlighted the implications of p53 mutations in cancer, p53 ubiquitination mechanistic details, targeting p53-MDM2/MDMX interactions, significant discoveries related to MDM2 inhibitor drug development, MDM2 and MDMX dual target inhibitors, and clinical trials with p53-MDM2/MDMX-targeted drugs. We also investigated potential therapeutic repurposing of selective estrogen receptor modulators (SERMs) in targeting p53-MDM2/MDMX interactions. Molecular docking studies of SERMs were performed utilizing the solved structures of the p53/MDM2/MDMX proteins. These studies identified ormeloxifene as a potential dual inhibitor of p53/MDM2/MDMX interaction, suggesting that repurposing SERMs for dual targeting of p53/MDM2 and p53/MDMX interactions is an attractive strategy for targeting wild-type p53 tumors and warrants further preclinical research.

Interactions of Selective Serotonin Reuptake Inhibitors with ß-Amyloid.

Treating Alzheimer's disease (AD) is a major challenge at the moment with no new drugs available to cure this devastating neurodegenerative disorder. In this regard, drug repurposing, which aims to determine novel therapeutic usage for drugs already approved by the regulatory agencies, is a pragmatic approach to discover novel treatment strategies. Selective serotonin reuptake inhibitors (SSRIs) are a known class of United States Food and Drug Administration approved drugs used in the treatment of depression. We investigated the ability of SSRIs fluvoxamine, fluoxetine, paroxetine, sertraline, and escitalopram on Aß42 aggregation and fibrillogenesis. Remarkably, the aggregation kinetic experiments carried out demonstrate the anti-Aß42 aggregation activity of SSRIs fluoxetine, paroxetine, and sertraline at all the tested concentrations (1, 10, 50, and 100 µM). Both fluoxetine and paroxetine were identified as the most promising SSRIs, showing 74.8 and 76% inhibition of Aß42 aggregation at 100 µM. The transmission electron microscopy experiments and dot-blot study also demonstrate the ability of fluoxetine and paroxetine to prevent Aß42 aggregation and fibrillogenesis, providing further evidence. Investigating the binding interactions of fluoxetine and paroxetine in the Aß42 oligomer and fibril models derived from the solid-state NMR structure suggests that these SSRIs interact at a region close to the N-terminal (Lys16-Glu22) in the S-shaped cross-ß-strand assembly and reduce Aß42 fibrillogenesis. On the basis of this study, a pharmacophore model is proposed which shows that the minimum structural requirements to design novel Aß42 aggregation inhibitors include the presence of one ionizable group, one hydrophobic group, two aromatic rings, and two hydrogen bond donor groups. These studies demonstrate that SSRIs have the potential to prevent Aß42 aggregation by direct binding and could be beneficial to AD patients on SSRIs.

{Ni4} Cubanes from enantiomerically pure 2-(1-hydroxyethyl)pyridine ligands: supramolecular chirality.

Homometallic {NiII4} cubane-like clusters with a rare chiral core have been prepared via the employment of enantiomerically pure 2-(1-hydroxyethyl)pyridine (Hmpm). Comparison with the achiral cubanes derived from the related 2-pyridinemethanol (Hpym) ligand reveals drastic structural changes as a consequence of the transfer of chirality from the ligands to the whole structure. Their magnetic properties have been related to the structural features of their cubane-type cores.

Drug-Induced Metabolic Acidosis.

Metabolic acidosis could emerge from diseases disrupting acid-base equilibrium or from drugs that induce similar derangements. Occurrences are usually accompanied by comorbid conditions of drug-induced metabolic acidosis, and clinical outcomes may range from mild to fatal. It is imperative that clinicians not only are fully aware of the list of drugs that may lead to metabolic acidosis but also understand the underlying pathogenic mechanisms. In this review, we categorized drug-induced metabolic acidosis in terms of pathophysiological mechanisms, as well as individual drugs' characteristics.

Residual dyslipidemia among United States adults treated with lipid modifying therapy (data from National Health and Nutrition Examination Survey 2009-2010).

Despite available medications for dyslipidemia, many treated patients still have suboptimal lipid levels. The aim of this study was to examine the extent of residual dyslipidemia in United States adults. Of 2509 United States adults aged ≥18 years from the National Health and Nutrition Examination Survey (NHANES) 2009-2010, 1,129 (41.8% weighted) had hyperlipidemia on the basis of modified treatment guidelines for low-density lipoprotein (LDL) cholesterol according to risk category or pharmacologic treatment. Of these, 484 (42.4%) were treated with lipid-modifying therapy, and the proportions of subjects who still had LDL cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides, or non-HDL cholesterol not at recommended levels were examined. In this cohort treated for hyperlipidemia, the mean age was 60.1 ± 14.9 years, and 52% were men. Only 36.5% of subjects receiving treatment for hyperlipidemia were at goal or normal levels for all 3 lipids (LDL cholesterol, HDL cholesterol, and triglycerides). LDL cholesterol remained higher than goal for 37.5% of subjects, 28.9% had low HDL cholesterol, and 36.3% had elevated triglycerides. One, 2, and 3 lipid parameters were at abnormal levels in 32.4%, 23.0%, and 8.2% of subjects, respectively; 36.5% had no lipid disorder. In addition, 38.6% of treated subjects were above non-HDL cholesterol goal, and even in those at LDL cholesterol goal, 12.9% were not at non-HDL cholesterol goal. Those with cardiovascular disease conditions had poorer goal attainment of LDL cholesterol, HDL cholesterol, and composite all lipids than those without cardiovascular disease. In conclusion, despite widely available treatments for dyslipidemia, many patients remain at suboptimal lipid levels, indicating need for greater adherence to lifestyle and medical therapies to address these gaps in the management of dyslipidemia.

Design, synthesis, and evaluation of fimbrolide-nitric oxide donor hybrids as antimicrobial agents.

Fimbrolides from marine algae have shown promising activity against quorum sensing (QS), a chief regulatory and communication system in bacteria controlling biofilm formation and virulence factor. Nitric oxide (NO) at sublethal concentration has also been reported to induce dispersal of bacterial biofilms and increase their susceptibility toward standard biocides and antibiotics. Therefore, the combination of QS inhibitors and NO donors has the potential to control the development of biofilm and promote their dispersion via a nonbactericidal mechanism. Inspired by these ideas, novel fimbrolide-NO donor hybrid compounds were designed and synthesized. Fimbrolide-NO hybrids 6b, 6f, and 14a were found to be particularly effective as antimicrobials compared to the nonhybrid natural fimbrolides as revealed by bioluminescent P. aeruginosa QS reporter assays and biofilm inhibition assays. Significantly, these fimbrolide-NO hybrids represent the first dual-action antimicrobial agent based on the baterial QS inhibition and NO signaling.