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Zongwang Ma, Jiangchun Hu
Certain Bacillus species have the capacity to produce cyclic lipopeptides and these lipopeptides are promising determinants contributing to the biocontrol of plant diseases. In the current study, a cyclic lipopeptide plipastatin A1 was isolated from the fermentation broth of a marine sediment-derived Bacillus amyloliquefaciens SH-B74 by the combination of solid-phase extraction and reversed-phase high-performance liquid chromatography, and its structure was identified by tandem mass spectrometry, high-resolution electro-spray ionization mass spectrometry, and gas chromatography-mass spectrometry together with nuclear magnetic resonance analysis...
February 2018: 3 Biotech
Anna Müller, Fabian Grein, Andreas Otto, Kathrin Gries, Dmitriy Orlov, Vladimir Zarubaev, Myriam Girard, Xinwei Sher, Olga Shamova, Terry Roemer, Patrice François, Dörte Becher, Tanja Schneider, Hans-Georg Sahl
The first-in-class lipopeptide antibiotic daptomycin (DAP) is highly active against Gram-positive pathogens including ß-lactam and glycopeptide resistant strains. Its molecular mode of action remains enigmatic, since a defined target has not been identified so far and multiple effects, primarily on the cell envelope have been observed. Reduced DAP susceptibility has been described in S. aureus and enterococci after prolonged treatment courses. In line with its pleiotropic antibiotic activities, a unique, defined molecular mechanism of resistance has not emerged, instead non-susceptibility appears often accompanied by alterations in membrane composition and changes in cell wall homeostasis...
December 21, 2017: International Journal of Medical Microbiology: IJMM
Mandana Ohadi, Gholamreza Dehghannoudeh, Hamid Forootanfar, Mojtaba Shakibaie, Majid Rajaee
In the present study the produced biosurfactant of Acinetobacter junii B6 (recently isolated from Iranian oil excavation site) were partially purified and identified by high performance thin layer chromatography (HPTLC), Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (1H NMR). Elemental analysis of the biosurfactant by energy dispersive X-ray spectroscopy (EDS) revealed that the biosurfactant was anionic in nature. The physiochemical properties of the lipopeptide biosurfactant were evaluated by determination of its critical micelle concentration (CMC) and hydrophile-lipophile balance (HLB)...
February 6, 2018: International Journal of Biological Macromolecules
Yuanmei Zhu, Xiujuan Zhang, Xiaohui Ding, Huihui Chong, Sheng Cui, Jinsheng He, Xinquan Wang, Yuxian He
Enfuvirtide (T20) is the only viral fusion inhibitor approved for clinical use, but it has relatively weak anti-HIV activity and easily induces drug resistance. In succession to T20, T1249 has been designed as a 39-mer peptide composed of amino acid sequences derived from HIV-1, HIV-2, and simian immunodeficiency virus (SIV); however, its development has been suspended due to formulation difficulties. We recently developed a T20-based lipopeptide (LP-40) showing greatly improved pharmaceutical properties. Here, we generated a T1249-based lipopeptide, termed LP-46, by replacing its C-terminal tryptophan-rich sequence with fatty acid...
February 7, 2018: Journal of Biological Chemistry
Chunshan Quan, Jing Liu, Wei Zhou, Wei Zheng, Liming Jin, Jing Zhao, Pengchao Zhao, Shengdi Fan
Cyclic lipopeptide has extensive application prospect in the field of medicine due to its unique chemical structure and biological activity. This study aims to obtain high purity of cyclic lipopeptide monomer from Bacillus amyloliquefaciems strain Q-426, and illuminate preliminary antitumor mechanism of C-15 Bacillomycin D and C-16 Bacillomycin D. Firstly, crude cyclic lipopeptide solution was prepared by two-steps purification of acid precipitation and double-resins chromatography. In order to obtain purer product preparative HPLC was utilized to separate and purify cyclic lipopeptide...
February 25, 2018: Sheng Wu Gong Cheng Xue Bao, Chinese Journal of Biotechnology
Yazen Yaseen, Awa Diop, Frédérique Gancel, Max Béchet, Philippe Jacques, Djamel Drider
Bacillus subtilis is a wealth source of lipopeptide molecules such as iturins, surfactins and fengycins or plipastatins endowed with a range of biological activities. These molecules, designated secondary metabolites, are synthesized via non-ribosomal peptides synthesis (NRPS) machinery and are most often subjected to a complex regulation with involvement of several regulatory factors. To gain novel insights on mechanism regulating fengycin production, we investigated the effect of the fascinating polynucleotide phosphorylase (PNPase), as well as the effect of lipopeptide surfactin...
February 8, 2018: Archives of Microbiology
Izabela Błażewicz, Maciej Jaśkiewicz, Lidia Piechowicz, Damian Neubauer, Roman J Nowicki, Wojciech Kamysz, Wioletta Barańska-Rybak
Introduction: Daptomycin is a cyclic lipopeptide that is bactericidal against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), vancomycin-intermediate S. aureus (VISA) and vancomycin-resistant S. aureus (VRSA) strains. Daptomycin exerts its antimicrobial effect by a calcium-dependent interaction with the cytoplasmic membrane resulting in depolarization, ion loss and rapid cell death. Unfortunately, loss of daptomycin susceptibility in S. aureus in the clinical setting has been noted...
December 2017: Postȩpy Dermatologii i Alergologii
A-Long Cui, Xin-Xin Hu, Yan Gao, Jie Jin, Hong Yi, Xiu-Kun Wang, Tong-Ying Nie, Yang Chen, Qi-Yang He, Huifang Guo, Jian-Dong Jiang, Xue-Fu You, Zhuo-Rong Li
In this paper, twenty-six natural polymyxin components and a new derivative S2 were synthesized, and their differences in efficacy and toxicity have been investigated. Almost all of the synthesized components showed strong activity against both susceptible and resistant strains of E. coli, K. pneumoniae, P. aeruginosa, and A. baumannii. The toxicities were obviously different between the components. Only some of the components were tested for toxicity in vivo. Compounds E2, E2-Val, A2, M2, D2, and S2 showed obviously lower renal cytotoxicity and acute toxicity than polymyxins B and E...
February 7, 2018: Journal of Medicinal Chemistry
Shuai Luo, Xin-Ai Chen, Xu-Ming Mao, Yong-Quan Li
Daptomycin is a cyclic lipopeptide antibiotic produced by Streptomyces roseosporus in an acidic peptide complex A21978C. In this complex, A21978C1-3 is most abundant and contains branched-chain fatty acyl groups, while daptomycin has a straight decanoic acyl group. The branched-chain α-keto acid dehydrogenase complex (BCDH complex), encoded by bkd gene clusters in Streptomyces, is responsible for the early step of converting branched-chain amino acids into branched-chain fatty acids. In a daptomycin industrial producer S...
February 7, 2018: Journal of Industrial Microbiology & Biotechnology
Gayan Heruka De Zoysa, Hugh Douglas Glossop, Vijayalekshmi Sarojini
Novel antifungal agents are required against pathogenic fungi such as Candida albicans. We report the anticandidal activity of battacin lipopeptide antibiotics with previously unexplored antifungal activity. From amongst sixteen battacin lipopeptides tested against C. alibicans (SC5314) the 4-methyl hexanoyl conjugated trimeric lipopeptide 13 emerged as the lead candidate with a MIC of 6.25 μM and negligible haemolysis of mouse red blood cells. The potency of this lipopeptide was maintained under acidic conditions...
January 9, 2018: European Journal of Medicinal Chemistry
Tony Velkov, Alejandra Gallardo-Godoy, James D Swarbrick, Mark A T Blaskovich, Alysha G Elliott, Meiling Han, Philip E Thompson, Kade D Roberts, Johnny X Huang, Bernd Becker, Mark S Butler, Lawrence H Lash, Sónia Troeira Henriques, Roger L Nation, Sivashangarie Sivanesan, Marc-Antoine Sani, Frances Separovic, Haydyn Mertens, Dieter Bulach, Torsten Seemann, Jeremy Owen, Jian Li, Matthew A Cooper
Resistance to the last-resort antibiotic colistin is now widespread and new therapeutics are urgently required. We report the first in toto chemical synthesis and pre-clinical evaluation of octapeptins, a class of lipopeptides structurally related to colistin. The octapeptin biosynthetic cluster consisted of three non-ribosomal peptide synthetases (OctA, OctB, and OctC) that produced an amphiphilic antibiotic, octapeptin C4, which was shown to bind to and depolarize membranes. While active against multi-drug resistant (MDR) strains in vitro, octapeptin C4 displayed poor in vivo efficacy, most likely due to high plasma protein binding...
January 23, 2018: Cell Chemical Biology
Peipei Xu, Hui Zeng, Min Zhou, Jian Ouyang, Bing Chen, Qiguo Zhang
RATIONALE: Hemophagocytic lymphohistiocytosis (HLH) secondary to methicillin-resistant Staphylococcus epidermidis (MRSE)-related left-sided infectious endocarditis had never been reported before. In the last decade, daptomycin, a novel lipopeptide antibiotic, showed its excellent role in anti-Gram-positive bacteria, including soft tissue infection, bloodstream and deep tissueinfection. PATIENT CONCERNS: An Asian women under sever condition due to the cooccurrence of HLH and MRSE-related endocarditis while also be allergic to vancomycin...
December 2017: Medicine (Baltimore)
Madiha Basit, Muhammad Hidayat Rasool, Syed Ali Raza Naqvi, Muhammad Waseem, Bilal Aslam
Present study was designed to evaluate the biosurfactant production potential by native strains of Bacillus cereus as well as determine their antimicrobial and antioxidant activities. The strains isolated from garden soil were characterized as B. cereus MMIC 1, MMIC 2 and MMIC 3. Biosurfactants were extracted as grey white precipitates. Optimum conditions for biosurfactant production were 37°C, the 7th day of incubation, 0.5% NaCl, pH 7.0. Moreover, corn steep liquor was the best carbon source. Biuret test, Thin Layer Chromatography (TLC), agar double diffusion and Fourier Transform Infrared Spectroscopy (FTIR) characterized the biosurfactants as cationic lipopeptides...
January 2018: Pakistan Journal of Pharmaceutical Sciences
Sreyoshi Sur, Tod D Romo, Alan Grossfield
Fengycin is a cyclic lipopeptide which is used as an agricultural fungicide. It is synthesized by Bacillus subtilis as an immune response against fungal infection, and functions by damaging the target's cell membrane. Previous molecular dynamics simulations and experiments led to the hypothesis that aggregation of fengycins on the membrane surface plays a key role in cell disruption. Here, we used microsecond scale all-atom molecular dynamics simulation to understand the specificity, selectivity, and structure of fengycin oligomers...
January 27, 2018: Journal of Physical Chemistry. B
Ali Abdelmoteleb, Rosalba Troncoso-Rojas, Tania Gonzalez-Soto, Daniel González-Mendoza
The ability of Bacillus subtilis, strain ALICA to produce three mycolytic enzymes (chitinase, β-1,3-glucanase, and protease), was carried out by the chemical standard methods. Bacillus subtilis ALICA was screened based on their antifungal activity in dual plate assay and cell-free culture filtrate (25%) against five different phytopathogenic fungi Alternaria alternata, Macrophomina sp., Colletotrichum gloeosporioides, Botrytis cinerea, and Sclerotium rolfesii. The B. subtilis ALICA detected positive for chitinase, β-1,3-glucanase and protease enzymes...
December 2017: Mycobiology
Joachim Vater, Stefanie Herfort, Joerg Doellinger, Max Weydmann, Peter Lasch, Rainer Borriss
Paenibacillus polymyxa strains are qualified for agrobiotechnological uses such as plant growth promotion and for biocontrol strategies against deleterious phytopathogenic competitors in the soil depending on their attractive arsenal of bioactive compounds. On the other hand they are potent producers of antibiotics for medical applications. To identify new products of such organisms genome mining strategies in combination with mass spectrometry are the methods of choice. Here we performed such studies with the Paenibacillus strain E681...
January 25, 2018: Chembiochem: a European Journal of Chemical Biology
Johanna Mattay, Stefanie Houwaart, Wolfgang Hüttel
Echinocandins are antifungal nonribosomal hexapeptides produced by fungi. Two of the amino acids are hydroxy-l-prolines: trans-4-hydroxy-l-proline and, in most echinocandin structures, (trans-2,3)-3-hydroxy-(trans-2,4)-4-methyl-l-proline. In the case of echinocandin biosynthesis by Glarea lozoyensis, both amino acids are found in pneumocandin A0, while in pneumocandin B0 the latter residue is substituted by trans-3- hydroxy-l-proline (3-Hyp). We have recently reported that all three amino acids are generated by the 2-oxoglutarate-dependent proline hydroxylase GloF...
January 19, 2018: Applied and Environmental Microbiology
Kamaluddeen Kabir, Yusuf Y Deeni, Simona M Hapca, Luke Moore, Andrew J Spiers
Bacterial bio-surfactants have a wide range of biological functions and biotechnological applications. Previous analyses had suggested a limit to their reduction of aqueous liquid surface tensions (γMin), and here we confirm this in an analysis of 25 Pseudomonas spp. strains isolated from soil which produce high-strength surfactants that reduce surface tensions to 25.2 ± 0.1-26.5 ± 0.2 mN.m-1 (the surface tension of sterile growth medium and pure water was 52.9 ± 0.4 mN.m-1 and 72.1 ± 1.2 mN.m-1, respectively)...
January 16, 2018: FEMS Microbiology Letters
Thomas E Schultz, Karl-Heinz Wiesmüller, Megan Lucas, Karen M Dobos, Alan G Baxter, Antje Blumenthal
Radioprotective 105 kDa (RP105, CD180) is a member of the Toll-like receptor (TLR) family that interacts with TLR2 and facilitates recognition of mature lipoproteins expressed by Mycobacterium tuberculosis and Mycobacterium bovis BCG. In this study, we used synthetic lipopeptide analogs of the M. tuberculosis 19 kDa lipoprotein to define structural characteristics that promote RP105-mediated host cell responses. A tripalmitoylated lipopeptide composed of the first 16 N-terminal amino acids of the M. tuberculosis 19 kDa lipoprotein induced RP105-dependent TNF and IL-6 production by macrophages...
January 9, 2018: Journal of Leukocyte Biology
Monica Cappelletti, Matthew J Lawson, Calvin C Chan, Adrienne N Wilburn, Senad Divanovic
Preterm birth (PTB) is the leading cause of neonatal mortality worldwide. Infection and inflammation are considered main causes of PTB. Among multiple pathogens, Gram-positive bacteria are commonly linked with induction of PTB. Although activation of innate immune responses, via TLR2 engagement, by Gram-positive bacteria is a likely cause, whether induction of PTB depends on the potency of specific microbial components to induce Toll-like receptor (TLR)2-driven inflammation has not been elucidated. Here, we show that TLR2 activation by synthetic lipopeptides, Pam2Cys, and Pam3Cys specifically, variably influenced inflammation and subsequent induction of PTB...
December 28, 2017: Journal of Leukocyte Biology
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