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Hiroyuki Tada, Risako Suzuki, Eiji Nemoto, Hidetoshi Shimauchi, Kenji Matsushita, Haruhiko Takada
Interleukin-33 (IL-33) is an IL-1 cytokine family member that is involved in the development of chronic inflammatory diseases and the initiation of allergic inflammation in response to pathogens. Porphyromonas gingivalis is a primary pathogen that is involved in chronic periodontitis and its bacterial components induce inflammatory responses. Dendritic cells (DCs) recognize pathogen- associated molecular patterns by expression of pattern-recognition receptors, such as Toll-like receptors (TLRs). DCs play an essential role in resistance to infection and maintenance of mucosal immune system...
2017: Biomedical Research
François Coutte, Didier Lecouturier, Krasimir Dimitrov, Jean-Sébastien Guez, Frank Delvigne, Pascal Dhulster, Philippe Jacques
Lipopeoptides are amphiphilic compounds combining interesting physicochemical properties and biological activities. Due to their high foaming capacity in aerated bioreactor, the development of scalable bioprocesses for their production is a major bottleneck. In addition, the genes involved in the biosynthesis of these lipopeptides are mainly regulated by the quorum sensing, a global regulatory mechanism depending on cell density and known to be activated in biofilms. Several approaches have thus been considered in literature taking into account two criteria, on one side, to favor, control or avoid foam formation and on the other side, to use planktonic or immobilized (biofilm) cells...
June 21, 2017: Biotechnology Journal
Samara Mejri, Ali Siah, François Coutte, Maryline Magnin-Robert, Béatrice Randoux, Benoit Tisserant, François Krier, Philippe Jacques, Philippe Reignault, Patrice Halama
Innovation toward ecofriendly plant protection products compatible with sustainable agriculture and healthy food is today strongly encouraged. Here, we assessed the biocontrol activity of three cyclic lipopeptides from Bacillus subtilis (mycosubtilin, M; surfactin, S; fengycin, F) and two mixtures (M + S and M + S + F) on wheat against Zymoseptoria tritici, the main pathogen on this crop. Foliar application of these biomolecules at a 100-mg L(-1) concentration on the wheat cultivars Dinosor and Alixan, 2 days before fungal inoculation, provided significant reductions of disease severity...
June 21, 2017: Environmental Science and Pollution Research International
Nicholas C Harris, Michio Sato, Nicolaus A Herman, Frederick Twigg, Wenlong Cai, Joyce Liu, Xuejun Zhu, Jordan Downey, Ryan Khalaf, Joelle Martin, Hiroyuki Koshino, Wenjun Zhang
A putative lipopeptide biosynthetic gene cluster is conserved in many species of Actinobacteria, including Mycobacterium tuberculosis and M. marinum, but the specific function of the encoding proteins has been elusive. Using both in vivo heterologous reconstitution and in vitro biochemical analyses, we have revealed that the five encoding biosynthetic enzymes are capable of synthesizing a family of isonitrile lipopeptides (INLPs) through a thio-template mechanism. The biosynthesis features the generation of isonitrile from a single precursor Gly promoted by a thioesterase and a nonheme iron(II)-dependent oxidase homolog and the acylation of both amino groups of Lys by the same isonitrile acyl chain facilitated by a single condensation domain of a nonribosomal peptide synthetase...
June 20, 2017: Proceedings of the National Academy of Sciences of the United States of America
Terukazu Sanui, Masaaki Takeshita, Takao Fukuda, Urara Tanaka, Rehab Alshargabi, Yoshitomi Aida, Fusanori Nishimura
Tripalmitoyl-S-glyceryl-l-Cys-Ser-(Lys)4 (Pam3CSK4) is a highly conserved molecular motif found in various classes of lipoproteins. The requirement for leukocyte to respond to synthetic Pam3CSK4 were studied. Pam3CSK4 primed neutrophils for a respiratory burst in a serum-dependent manner. Pam3CSK4 upregulated CD11b, CD14, and cytochrome b558, and downregulated Leu-8. Treatment of neutrophils with anti-CD14 antibodies and treatment of serum with anti-LPS binding protein (LBP) antibodies resulted in the inhibition of priming for respiratory burst by Pam3CSK4...
June 17, 2017: International Immunopharmacology
Tomáš Galica, Pavel Hrouzek, Jan Mareš
Cyanobacterial lipopeptides exhibit antimicrobial and antifungal bioactivities with potential for use in pharmaceutical research. However, due to their haemolytic activity and cytotoxic effects against human cells, they may pose a health issue if produced in substantial amounts in the environment. In bacteria, lipopeptides can be synthesized via several well-evidenced mechanisms. In one of them, fatty acyl-AMP ligase (FAAL) initiates the biosynthesis by activation of a fatty acyl residue. We have performed a bioinformatic survey of the cyanobacterial genomic information available in the public databases for the presence of FAAL-containing non-ribosomal peptide synthetase/polyketide synthetase (NRPS/PKS) biosynthetic clusters, as a genetic basis for lipopeptide biosynthesis...
June 20, 2017: Journal of Phycology
Rajni Sharma, Arin Ghasparian, John A Robinson, Kenneth C McCullough
Dendritic cells (DCs) play critical roles in developing immune defenses. One important aspect is interaction with pathogen-associated molecular patterns (PAMPs)/danger-associated molecular patterns, including di- and triacylated lipopeptides. Isolated or synthetic lipopeptides are potent vaccine adjuvants, interacting with cell surface TLR2 heterodimers. In contrast, deep embedment within bacteria cell walls would impair lipopeptide interaction with cell surface TLR2, requiring degradation for PAMP recognition...
June 19, 2017: Journal of Immunology: Official Journal of the American Association of Immunologists
Feyisara E Olorunleke, Nam P Kieu, Evelien De Waele, Marc Timmerman, Marc Ongena, Monica Höfte
Cyclic lipopeptides (CLPs) are synthesized by nonribosomal peptide synthetases (NRPS), which are often flanked by LuxR-type transcriptional regulators. Pseudomonas sp. CMR12a, an effective biocontrol strain, produces two different classes of CLPs namely sessilins and orfamides. The orfamide biosynthesis gene cluster is flanked up- and downstream by LuxR-type regulatory genes designated ofaR1 and ofaR2, respectively, whereas the sessilin biosynthesis gene cluster has one LuxR-type regulatory gene which is situated upstream of the cluster and is designated sesR...
June 15, 2017: MicrobiologyOpen
Yeji Lee, Chanvorleak Phat, Soon-Cheol Hong
Many cyclic peptides and analogues derived from marine sources are known to possess biological properties, including anticancer, antitumor, antibacterial, antifungal, antiparasitic, anti-inflammation, anti-proliferative, anti-hypertensive, cytotoxic, and antibiotic properties. These compounds demonstrate different activities and modes of action according to their structure such as cyclic oligopeptide, cyclic lipopeptide, cyclic glycopeptide and cyclic depsipeptide. The recent advances in application of the above-mentioned cyclic peptides were reported in dolastatins, soblidotin, didemnin B, aplidine, salinosporamide A, kahalalide F and bryostatin 1 and they are currently in clinical trials...
June 10, 2017: Peptides
Chengjun Zhu, Fang Xiao, Yimin Qiu, Qin Wang, Zhili He, Shouwen Chen
Lichenysin is categorized into the family of lipopeptide biosurfactants and has a variety of applications in the petroleum industry, bioremediation, pharmaceuticals, and the food industry. Currently, large-scale production is limited due to the low yield. This study found that lichenysin production was repressed by supplementation of extracellular amino acids. The global transcriptional factor CodY was hypothesized to prevent lichenysin biosynthesis under an amino acid-rich condition in Bacillus licheniformis...
June 11, 2017: Applied Microbiology and Biotechnology
Parent Zihalirwa Kulimushi, Géant Chuma Basime, Gustave Mushagalusa Nachigera, Philippe Thonart, Marc Ongena
In the province of South Kivu (Democratic Republic of Congo), warm and humid climatic conditions favor the development and spreading of phytopathogens. The resulting diseases cause important losses in production both in crop and after harvest. In this study, we wanted to evaluate the potential of Bacillus amyloliquefaciens as biocontrol agent to fight some newly isolated endemic fungal pathogens infesting maize. The strain S499 has been selected based on its high in vitro antagonistic activity correlating with a huge potential to secrete fungitoxic lipopeptides upon feeding on maize root exudates...
June 9, 2017: Environmental Science and Pollution Research International
Ivica Dimkić, Slaviša Stanković, Marija Nišavić, Marijana Petković, Petar Ristivojević, Djordje Fira, Tanja Berić
In this study the efficacy of two different methods for extracting lipopeptides produced by five Bacillus strains-ethyl acetate extraction, and acid precipitation followed by methanol extraction-was investigated using mass spectrometry. High performance thin layer chromatography (HPTLC) was also used for the simultaneous separation of complex mixtures of lipopeptide extracts and for the determination of antimicrobial activity of their components. The mass spectra clearly showed well-resolved groups of peaks corresponding to different lipopeptide families (kurstakins, iturins, surfactins, and fengycins)...
2017: Frontiers in Microbiology
Qin-Wei Yu, Hao Wang, Jing-Ting Huo, Xiao-Fei An, Peng Gao, Zhen-Zhou Jiang, Lu-Yong Zhang, Ming Yan
ETHNOPHARMACOLOGICAL RELEVANCE: Baeckea frutescens L. is commonly used as a folk medicinal material. There are nineteen components in its volatile oil, including Pcymol which has effects of eliminating phlegm, relieving asthma and antiviral. This study was aimed to investigate the anti-infectious inflammatory activities of Baeckea frutescens L. and its conponents and analyzing the mechanisms. MATERIALS AND METHODS: The anti-infectious inflammation of Baeckea frutescens L...
May 31, 2017: Journal of Ethnopharmacology
Ting Ding, Bo Su, Xiaojie Chen, Shanshan Xie, Shuangyue Gu, Qi Wang, Dayue Huang, Haiyang Jiang
Bacillus subtilis DZSY21 isolated from the leaves of Eucommia ulmoides oliv. was labeled by antibiotic marker and found to effectively colonize the leaves of maize plant. Agar diffusion assays and biocontrol effect experiments showed that strain DZSY21 and its lipopeptides had antagonistic activity against Bipolaris maydis, as well as high biocontrol effects on southern corn leaf blight caused by B. maydis. Using MALDI-TOF-MS analysis, we detected the presence of antimicrobial surfactin A, surfactin B, and fengycin in the strain DZSY21...
2017: Frontiers in Microbiology
Thando Ndlovu, Marina Rautenbach, Sehaam Khan, Wesaal Khan
The quantitative and qualitative effect of water immiscible and miscible carbon-rich substrates on the production of biosurfactants, surfactin and rhamnolipids, by Bacillus amyloliquefaciens ST34 and Pseudomonas aeruginosa ST5, respectively, was analysed. A small-scale high throughput 96 deep-well micro-culture method was utilised to cultivate the two strains in mineral salt medium (MSM) supplemented with the water miscible (glucose, glycerol, fructose and sucrose) and water immiscible carbon sources (diesel, kerosene and sunflower oil) under the same growth conditions...
December 2017: AMB Express
Thando Ndlovu, Marina Rautenbach, Johann Arnold Vosloo, Sehaam Khan, Wesaal Khan
Biosurfactants are unique secondary metabolites, synthesised non-ribosomally by certain bacteria, fungi and yeast, with their most promising applications as antimicrobial agents and surfactants in the medical and food industries. Naturally produced glycolipids and lipopeptides are found as a mixture of congeners, which increases their antimicrobial potency. Sensitive analysis techniques, such as liquid chromatography coupled to mass spectrometry, enable the fingerprinting of different biosurfactant congeners within a naturally produced crude extract...
December 2017: AMB Express
Marina Rautenbach, N Maré Vlok, Hans A Eyéghé-Bickong, Marthinus J van der Merwe, Marietjie A Stander
It was previously observed that the lipopeptide surfactants in surfactin (Srf) have an antagonistic action towards the highly potent antimicrobial cyclodecapeptide, gramicidin S (GS). This study reports on some of the molecular aspects of the antagonism as investigated through complementary electrospray ionization mass spectrometry techniques. We were able to detect stable 1:1 and 2:1 hetero-oligomers in a mixture of surfactin and gramicidin S. The noncovalent interaction between GS and Srf, with the proposed equilibrium: GS~Srf↔GS+Srf correlated to apparent K d values of 6-9 μM in gas-phase and 1 μM in aqueous solution...
May 30, 2017: Journal of the American Society for Mass Spectrometry
Yulin Chen, Shiliang A Liu, Haijin Mou, Yunxiao Ma, Meng Li, Xiaoke Hu
Antibiotic resistance has become one of the world's most severe problems because of the overuse of antibiotics. Antibiotic-resistant bacteria are more difficult to kill and more expensive to treat. Researchers have been studied on antibiotic alternatives such as antimicrobial peptides and lipopeptides. A functional bacteria MB01 producing lipopeptides which can be used as bacteriostat was isolated from the Bohai Sea sediments, which had been identified as Bacillus licheniformis by the morphological, physiological, and biochemical identification and 16s rDNA sequence...
2017: Frontiers in Microbiology
J Goret, L Béven, B Faustin, C Contin-Bordes, C Le Roy, S Claverol, H Renaudin, C Bébéar, S Pereyre
Mycoplasma hominis lacks a cell wall and lipoproteins anchored to the extracellular side of the plasma membrane are in direct contact with the host components. A Triton X-114 extract of M. hominis enriched with lipoproteins was shown to stimulate the production of IL-23 by human dendritic cells (hDCs). The inflammasome activation of the host cell has never been reported upon M. hominis infection. We studied here the interaction between M. hominis PG21 and hDCs by analyzing both the inflammation-inducing mycoplasmal lipoproteins and the inflammasome activation of the host cell...
May 30, 2017: Journal of Bacteriology
Ana C Rodrigo, Stephen M Bromfield, Erik Laurini, Paola Posocco, Sabrina Pricl, David K Smith
Tuning molecular structures of self-assembling multivalent (SAMul) dendritic cationic lipopeptides controls the self-assembled morphology. In buffer, spherical micelles formed by higher generation systems bind polyanionic heparin better than worm-like micelles formed by lower generation systems. In human serum, the binding of spherical micelles to heparin is adversely affected, while worm-like micelles maintain their relative binding ability.
June 8, 2017: Chemical Communications: Chem Comm
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