keyword
MENU ▼
Read by QxMD icon Read
search

lipopeptides

keyword
https://www.readbyqxmd.com/read/28108091/implementation-of-a-simple-innovative-system-for-postprescription-antibiotic-review-based-on-computerized-tools-with-shared-access
#1
F Bouchand, A Dinh, A L Roux, B Davido, H Michelon, M Lepainteur, B Legendre, F El Sayed, I Pierre, J Salomon, C Lawrence, C Perronne, M Villart, A-C Crémieux
BACKGROUND: Controlling antibiotic use in healthcare establishments limits their consumption and the emergence of bacterial resistance. AIM: To evaluate the efficiency of an innovative antibiotic stewardship strategy implemented over three years in a university hospital. METHODS: An antimicrobial multi-disciplinary team (AMT) [pharmacist, microbiologist and infectious disease specialist (IDS)] conducted a postprescription review. Specific coding of targeted antibiotics (including broad-spectrum β-lactams, glycopeptides, lipopeptides, fluoroquinolones and carbapenems) in the computerized physician order entry allowed recording of all new prescriptions...
November 26, 2016: Journal of Hospital Infection
https://www.readbyqxmd.com/read/28107619/peptide-based-stealth-nanoparticles-for-targeted-and-ph-triggered-delivery
#2
Alessandro Ranalli, Melissa Santi, Luigi Capriotti, Valerio Voliani, David Porciani, Fabio Beltram, Giovanni Signore
Stealth agents are extensively investigated as means to prolong nanostructures residence time in the bloodstream by avoiding uptake by the reticuloendothelial system. Unfortunately, commonly used agents such as poly(ethylene glycol) can adversely impact on targeting efficiency and promote immune reaction by the host organism. Therefore, there is an increasing interest in developing biocompatible, non-PEGylated organic nanostructures able to perform targeted delivery, to increase the efficacy of liposomal technology...
January 20, 2017: Bioconjugate Chemistry
https://www.readbyqxmd.com/read/28106348/a-biosurfactant-inspired-heptapeptide-with-improved-specificity-to-kill-mrsa
#3
Yuan Liu, Shuangyang Ding, Richard Dietrich, Erwin Märtlbauer, Kui Zhu
The emergence and rapid spread of methicillin-resistant Staphylococcus aureus (MRSA) poses a serious threat to public health. New antibiotics and strategies are urgently needed to combat S. aureus associated infections. Bacaucin, a novel cyclic lipopeptide from Bacillus subtilis CAU21, is reported. Bacaucin shows broad antibacterial activity against Gram-positive bacteria, but is also hemolytic and cytotoxic. However, bacaucin-1, a bacaucin-inspired ring-opened heptapeptide, shows specific antibacterial activity against MRSA by a membrane-disruptive mechanism without detectable toxicity to mammalian cells or induction of bacterial resistance...
February 1, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28099806/melting-behavior-of-zipper-structured-lipopeptides-in-lipid-bilayer
#4
Sijia Wang, Xia Han, Danyang Liu, Mengya Li, Shouhong Xu, Honglai Liu
A zipper-structured lipopeptide is expected to play a role of "intelligent valve" in the lipid bilayer. In this paper, a series of zipper-structured lipopeptides have been designed for preparing thermo-controllable hybrid liposomes. Their conformational transition as a function of temperature in lipid bilayer has been investigated for understanding the influences of molecular structure and bilayer property on bio-function. The melting temperatures Tm of the lipopeptides have been found to depend on their molecular structures...
January 18, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28075053/synthesis-characterization-and-immunological-evaluation-of-self-adjuvanting-group-a-streptococcal-vaccine-candidates-bearing-various-lipidic-adjuvanting-moieties
#5
Vincent Fagan, Waleed M Hussein, Mei Su, Ashwini K Gidda, Michael R Batzloff, Michael F Good, Istvan Toth, Pavla Simerska
Four group A streptococcal glyco-lipopeptide vaccine candidates were prepared and characterized, each possessing different lipidic adjuvanting moieties. The immunogenicity of the compounds was evaluated by macrophage and dendritic cell uptake studies and by in vivo quantification of systemic IgG antibody using ELISA. Three of the four vaccine candidates showed a significant induction of IgG response compared to a negative control.
January 11, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/28073163/hydrocarbon-stapled-lipopeptides-exhibit-selective-antimicrobial-activity
#6
Zachary B Jenner, Christopher M Crittenden, Martín Gonzalez, Jennifer S Brodbelt, Kerry A Bruns
Antimicrobial peptides (AMPs) occur widely in nature and have been studied for their therapeutic potential. AMPs are of interest due to the large number of possible chemical structural combinations using natural and unnatural amino acids, with varying effects on their biological activities. Using physicochemical properties from known naturally occurring amphipathic cationic AMPs, several hydrocarbon-stapled lipopeptides (HSLPs) were designed, synthesized, and tested for antimicrobial properties. Peptides were chemically modified by N-terminal acylation, C-terminal amidation, and some were hydrocarbon stapled by intramolecular olefin metathesis...
January 10, 2017: Biopolymers
https://www.readbyqxmd.com/read/28071053/functional-characterization-of-the-unique-terminal-thioesterase-domain-from-polymyxin-synthetase
#7
Charles A Galea, Kade D Roberts, Yan Zhu, Philip E Thompson, Jian Li, Tony Velkov
Polymyxins remain one of the few antibiotics available for treating antibiotic resistant bacteria. Here we describe polymyxin B thioesterase which performs the final step in polymyxin B biosynthesis. Isolated thioesterase catalyzed cyclization of an N-acetylcystamine polymyxin B analogue to form polymyxin B. The thioesterase contained a catalytic cysteine unlike most thioesterases which possess a serine. Supporting this, incubation of polymyxin B thioesterase with reducing agents abolished enzymatic activity while mutation of the catalytic cysteine to serine significantly decreased activity...
January 10, 2017: Biochemistry
https://www.readbyqxmd.com/read/28045164/bicyclic-enol-cyclocarbamates-inhibit-penicillin-binding-proteins
#8
Paul Dockerty, Jerre G Edens, Menno B Tol, Danae Morales Angeles, Arnau Domenech, Yun Liu, Anna K H Hirsch, Jan-Willem Veening, Dirk-Jan Scheffers, Martin D Witte
Natural products form attractive leads for the development of chemical probes and drugs. The antibacterial lipopeptide Brabantamide A contains an unusual enol cyclocarbamate and we used this scaffold as inspiration for the synthesis of a panel of enol cyclocarbamate containing compounds. By equipping the scaffold with different groups, we identified structural features that are essential for antibacterial activity. Some of the derivatives block incorporation of hydroxycoumarin carboxylic acid-amino d-alanine into the newly synthesized peptidoglycan...
January 3, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28040465/toll-like-receptor-2-promiscuity-is-responsible-for-the-immunostimulatory-activity-of-nucleic-acid-nanocarriers
#9
Malvina Pizzuto, Monique Gangloff, Daniel Scherman, Nicholas J Gay, Virginie Escriou, Jean-Marie Ruysschaert, Caroline Lonez
Lipopolyamines (LPAs) are cationic lipids; they interact spontaneously with nucleic acids to form lipoplexes used for gene delivery. The main hurdle to using lipoplexes in gene therapy lies in their immunostimulatory properties, so far attributed to the nucleic acid cargo, while cationic lipids were considered as inert to the immune system. Here we demonstrate for the first time that di-C18 LPAs trigger pro-inflammatory responses through Toll-like receptor 2 (TLR2) activation, and this whether they are bound to nucleic acids or not...
December 28, 2016: Journal of Controlled Release: Official Journal of the Controlled Release Society
https://www.readbyqxmd.com/read/28038833/structure-activity-relationship-of-daptomycin-analogues-with-substitution-at-2s-3r-3-methyl-glutamic-acid-position
#10
Du'an Lin, Hiu Yung Lam, Wenbo Han, Nicole Cotroneo, Bhaumik A Pandya, Xuechen Li
Daptomycin is a highly effective lipopeptide antibiotic against Gram-positive pathogens. The presence of (2S, 3R) 3-methyl glutamic acid (mGlu) in daptomycin has been found to be important to the antibacterial activity. However the role of (2S, 3R) mGlu is yet to be revealed. Herein, we reported the syntheses of three daptomycin analogues with (2S, 3R) mGlu substituted by (2S, 3R) methyl glutamine (mGln), dimethyl glutamic acid and (2S, 3R) ethyl glutamic acid (eGlu), respectively, and their antibacterial activities...
December 18, 2016: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/28025839/biological-and-structural-effects-of-the-conjugation-of-an-antimicrobial-decapeptide-with-saturated-unsaturated-methoxylated-and-branched-fatty-acids
#11
María Verónica Húmpola, María Carolina Rey, Nestor M Carballeira, Arturo Carlos Simonetta, Georgina Guadalupe Tonarelli
The increasing bacterial resistance against conventional antibiotics has led to the search for new antimicrobial drugs with different modes of action. Cationic antimicrobial peptides (AMPs) and lipopeptides are promising candidates to treat infections because they act on bacterial membranes causing rapid destruction of sensitive bacteria. In this study, a decapeptide named A2 (IKQVKKLFKK) was conjugated at the N-terminus with saturated, unsaturated, methoxylated and methyl -branched fatty acids of different chain lengths (C8 - C20), the antimicrobial and structural properties of the lipopeptides being then investigated...
December 26, 2016: Journal of Peptide Science: An Official Publication of the European Peptide Society
https://www.readbyqxmd.com/read/28024522/brevibacillin-a-cationic-lipopeptide-that-binds-to-lipoteichoic-acid-and-subsequently-disrupts-cytoplasmic-membrane-of-staphylococcus-aureus
#12
Xu Yang, En Huang, Ahmed E Yousef
Brevibacillin is a newly-discovered antimicrobial lipopeptide produced by Brevibacillus laterosporus OSY-I1. It is active against Gram-positive bacteria, including antibiotic resistant strains. This research was initiated to investigate the mechanism of action of brevibacillin against an indicator strain, Staphylococcus aureus ATCC 6538. Results of the study proved that brevibacillin binds to lipoteichoic acid (LTA) on cell wall before interacting with cell membrane. Additionally, brevibacillin disrupts S. aureus cytoplasmic membrane by increasing its permeability, depolarization and potassium leakage...
January 2017: Microbiological Research
https://www.readbyqxmd.com/read/28019119/evaluation-of-bacillus-subtilis-spb1-biosurfactant-effects-on-hyperglycemia-angiotensin-i-converting-enzyme-ace-activity-and-kidney-function-in-rats-fed-on-high-fat-high-fructose-diet
#13
Raida Zouari, Khaled Hamden, Abdelfattah El Feki, Khansa Chaabouni, Fatma Makni-Ayadi, Fahima Sallemi, Semia Ellouze-Chaabouni, Dhouha Ghribi-Aydi
This study investigated the protective and the curative effects of Bacillus subtilis SPB1 crude lipopeptide biosurfactant in alleviating induced obesity complications in rats fed on high-fat-high-fructose diet (HFFD). Male Wistar rats were divided into five groups with the following treatment schedule: normal diet-fed rats (CD), HFFD-fed rats, HFFD-fed rats supplemented with SPB1 biosurfactant from the first day of the experiment (HFFD + Bios1), rats fed on HFFD receiving standard drug (HFFD + Torva), or SPB1 biosurfactant (HFFD + Bios2) during the last 4 weeks of the study...
December 25, 2016: Archives of Physiology and Biochemistry
https://www.readbyqxmd.com/read/28011350/clinical-effectiveness-of-daptomycin-loading-dose-in-patients-infected-with-gram-positive-pathogens
#14
Hideo Kato, Mao Hagihara, Naoya Nishiyama, Yusuke Koizumi, Yuka Yamagishi, Katsuhiko Matsuura, Hiroshige Mikamo
This study was to evaluate the loading does of daptomycin, a novel lipopeptide antibacterial active against Gram-positive pathogens, on clinical efficiency. We divided patients received daptomycin therapy into 2 groups. One of two groups comprised patients received the loading dose of daptomycin on day 1 (group 1) and the other group received normal dosage (4-6 mg/kg/day) (group 2). Inflammatory markers were assessed at least 3 days before daptomycin therapy started as their baseline, and 2 weeks from daptomycin therapy started for the evaluation of clinical efficacy...
December 20, 2016: Journal of Infection and Chemotherapy: Official Journal of the Japan Society of Chemotherapy
https://www.readbyqxmd.com/read/28009004/translocation-of-the-thioesterase-domain-for-the-redesign-of-plipastatin-synthetase
#15
Ling Gao, Hongxia Liu, Zhi Ma, Jinzhi Han, Zhaoxin Lu, Chen Dai, Fengxia Lv, Xiaomei Bie
Non-ribosomal peptide synthetases (NRPSs) are large enzymatic complexes that catalyse the synthesis of biologically active peptides in microorganisms. Genetic engineering has recently been applied to reprogram NRPSs to produce lipopeptides with a new sequence. The carboxyl-terminal thioesterase (TE) domains from NRPSs catalyse cleavage products by hydrolysis or complex macrocyclization. In this study, we modified plipastatin synthetase by moving the intrinsic TE region to the end of the internal thiolation (T) domains, thus generating Bacillus subtilis strains that could produce new truncated cyclic or linear peptides of the predicted sequence, which further provided an important insight into the regioselectivity of plipastatin TE...
December 23, 2016: Scientific Reports
https://www.readbyqxmd.com/read/28006919/bacterial-analysis-by-laser-desorption-ionization-mass-spectrometry-on-amorphous-silicon
#16
Shin Hye Kim, Jeongkwon Kim, Seung-Hyun Jo, Jeong-Hoon Kim, Kyung Joong Kim, Sohee Yoon
Lipid profiling in nine bacterial species has been accomplished by laser desorption ionization mass spectrometry (LDI-MS) using amorphous silicon (a-Si) thin film with 100 nm thickness. Lipid ions could be generated by LDI on a-Si regardless of ion acquisition modes because of a thermal property of a-Si to govern laser-induced surface heating. In a comparative study of lipid profiling in Bacillus lichemiformis by LDI-MS and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), LDI-MS on a-Si shows a higher efficiency in lipid and lipopeptide detection than MALDI-MS...
December 22, 2016: Biointerphases
https://www.readbyqxmd.com/read/28003842/biomimetic-proopiomelanocortin-suppresses-capsaicin-induced-sensory-irritation-in-humans
#17
Sayed Ali Fatemi, Abbas Jafarian-Dehkordi, Valiollah Hajhashemi, Ali Asilian-Mahabadi
Sensitive skin is a frequently mentioned cosmetic complaint. Addition of a biomimetic of neuromediator has recently appeared as a promising new way to cure skin care product problems. This study was aimed to assess the inhibitory effect of a biomimetic lipopeptide derived from proopiomelanocortin (bPOMC) on capsaicin-induced sensory irritation in human volunteers and also to compare its protective effect with that of the well-known anti irritant strontium chloride. The effect of each test compound was studied on 28 selected healthy volunteers with sensitive skin in accordance with a double-blind vehicle-controlled protocol...
December 2016: Research in Pharmaceutical Sciences
https://www.readbyqxmd.com/read/27996239/cancer-cell-specific-delivery-of-photosystem-i-through-integrin-targeted-liposome-shows-significant-anticancer-activity
#18
Abhijit Saha, Saswat Mohapatra, Gaurav Das, Batakrishna Jana, Subhajit Ghosh, Debmalya Bhunia, Surajit Ghosh
Many anticancer drugs are developed for the treatment of cancer from natural sources. Photosystem I (PSI), a protein complex present in the chloroplast, is involved in photosynthesis and generates reactive oxygen species (ROS) in plant. Here, we used the ROS generation property of PSI for cancer therapy. We show that PSI can enter into different kinds of cancer cell like human lung carcinoma (A549) and mouse melanoma (B16F10) cell lines and generate ROS inside the cells. It inhibits the proliferation of cancer cell and causes apoptotic death of cancer cells...
December 20, 2016: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/27995738/novel-approach-to-determine-ghrelin-analogs-by-using-liquid-chromatography-with-mass-spectrometry-using-a-monolithic-column
#19
Jana Zemenova, David Sykora, Hana Adamkova, Lenka Maletinska, Tomas Elbert, Ales Marek, Miroslava Blechova
In our project, ghrelin analogs possessing enhanced stability and potential to significantly increase food intake were used. Three newly synthesized ghrelin analogs with fatty acid residues consisting of 8, 10, and 14 carbon atoms were studied. The main goal of this work was to develop a suitable analytical method for the determination of the stability of the novel ghrelin analogs in plasma. An appropriate liquid chromatography with mass spectrometry method was developed and optimized. The results obtained were compared with the data measured by using a commercial enzyme-linked immuno-sorbent assay kit, and a good correlation was found...
December 19, 2016: Journal of Separation Science
https://www.readbyqxmd.com/read/27992815/molecular-dynamics-study-of-micelles-properties-according-to-their-size
#20
S Lebecque, J M Crowet, M N Nasir, M Deleu, L Lins
Surfactants are molecules able to spontaneously self-assemble to form aggregates with well-defined properties, such as spherical micelles, planar bilayers, cylindrical micelles or vesicles. Micelles have notably several applications in many domains, such as drug delivery or membrane protein solubilization. In this context, the study of micelle formation in relation with the structural and physico-chemical properties of surfactants is of great interest to better control their use in the different application fields...
December 11, 2016: Journal of Molecular Graphics & Modelling
keyword
keyword
81314
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"