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Misugi Uraji, Haruka Tamura, Eiichi Mizohata, Jiro Arima, Kun Wan, Ken'ichi Ogawa, Tsuyoshi Inoue, Tadashi Hatanaka
Feruloyl esterases (FAEs) are key enzymes required for the production of ferulic acid from agricultural biomass. Previously, we identified and characterized R18, an FAE from Streptomyces cinnamoneus NBRC 12852, which showed no sequence similarity with the known FAEs. To determine the region involved in its catalytic activity, we constructed chimeric enzymes using R18 and its homolog (TH2-18) from S. cinnamoneus strain TH-2. Although R18 and TH2-18 showed 74% identity in their primary sequence, the recombinant proteins of these two FAEs (rR18 and rTH2-18) showed very different specific activities toward ethyl ferulate...
November 17, 2017: Applied and Environmental Microbiology
Andreas Bechthold, Songya Zhang, Jing Zhu, David Zechel, Claudia Jessen-Trefzer, Richard T Eastman, Thomas Paululat
In this study we report that Streptomyces asterosporus DSM 41452 is a producer of new molecules related to the non-ribosomal cyclodepsipeptide WS9326A and the polyketide Annimycin. S. asterosporus DSM 41452 is shown to produce six cyclodepsipeptides and peptides, WS9326A to G. Notably, the compounds WS9326F and WS9326G have not been de-scribed before. The genome of S. asterosporus DSM 41452 was sequenced and a putative WS9326A gene cluster was iden-tified. Gene deletion experiments confirmed that this cluster is responsible for the biosynthesis of WS9326A to G...
November 17, 2017: Chembiochem: a European Journal of Chemical Biology
Junwei Zhao, Linlin Shi, Wenchao Li, Jiabin Wang, Han Wang, Yuanyuan Tian, Wensheng Xiang, Xiangjing Wang
Two novel actinomycete isolates, designated strains NEAU-A4(T) and NEAU-A3, were isolated from rhizosphere soil of wheat (Triticumaestivum L.) and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics of the two strains coincided with those of the genus Streptomyces. The 16S rRNA gene sequence analysis showed that the two isolates exhibited 99.6 % 16S rRNA gene sequence similarity with each other and that they were most closely related to Streptomyces violaceorectus DSM 40279(T) (98...
November 16, 2017: International Journal of Systematic and Evolutionary Microbiology
V R Ranjitha, Ravishankar Rai Vittal
In the present study, the extracellular synthesis of Selenium nanoparticles (SeNPs) was carried out by using culture supernatant of Streptomyces griseoruber, an Actinomycetes member isolated from the soil. Bioreduction of SeNPs was confirmed by UV-Visible spectrophotometer that showed the peak at 575 nm. XRD pattern confirmed the non-crystalline or amorphous nature of the synthesised SeNPs. FTIR spectra revealed the possible functional group that is responsible for mediating the SeNPs formation. Size and distribution of the biosynthesised SeNPs were analysed by HR-TEM that showed the formation of particle size in the range of 100-250nm...
November 13, 2017: Pharmaceutical Nanotechnology
Ryuichi Sawa, Yumiko Kubota, Maya Umekita, Masaki Hatano, Chigusa Hayashi, Masayuki Igarashi
Drug-resistant bacteria are still emerging, and screening of new skeletal antibiotics is important. During our continuous screening for antimicrobial agents, we discovered a new antimicrobial, named quadoctomycin, from solid culture of Streptomyces sp. MM168-141F8. The substance was purified by solvent extraction, silica gel chromatography and HPLC. Structural elucidation of quadoctomycin was performed by MS and NMR analyses and chemical degradation. Quadoctomycin possesses a 48-membered polyol macrolide skeleton in which an α-D-mannoside is connected to C-22 by an O-glycosidic linkage...
November 15, 2017: Journal of Antibiotics
Mohammed Harir, Bellahcene Miloud, Maria Camilla Baratto, Simona Pollini, Gian Maria Rossolini, Lorenza Trabalzini, Enrico Fatarella, Rebecca Pogni
In the present study different actinomycete strains were collected and isolated from algerian Sahara soil with the aim to select novel enzymes with promising features for biotechnological applications. The Ms1 strain was selected, amongst the others, for its capability to produce melanin in different solid media. Ms1 chromosomal DNA was sequenced and the strain assigned to Streptomyces cyaneofuscatus sp. A tyrosinase (MW∼30kD) encoding sequence was identified and the corresponding enzyme was isolated and biochemically characterized...
November 10, 2017: Journal of Biotechnology
Lijuan Wang, Mengyi Zhu, Qingbo Zhang, Xu Zhang, Panlei Yang, Zihui Liu, Yun Deng, Yiguang Zhu, Xueshi Huang, Li Han, Shengqing Li, Jing He
A non-ribosomal peptide synthetase (NRPS) gene cluster (sfa) was identified in Streptomyces thioluteus to direct the biosynthesis of the diisonitrile antibiotic SF2768. Its biosynthetic pathway was reasonably proposed based on bioinformatics analysis, metabolic profiles of mutants and the elucidation of the intermediate and shunt product structures. Bioinformatics-based alignment found a putative ATP-binding cassette (ABC) transporter related to iron import within the biosynthetic gene cluster, which implied that the product might be a siderophore...
November 13, 2017: ACS Chemical Biology
Jessy Mariam, Ruchi Anand
Fluorescence spectroscopy is an important analytical tool which is widely employed to study biological systems. This technique can be applied to qualitatively and quantitatively probe protein-ligand interactions primarily because of its sensitivity, selectivity, nondestructive and rapid form of analysis. In this chapter we describe the utility of this technique to establish a label-free, universal screening protocol for putative γ-butyrolactone (GBL) receptors by exploiting the intrinsic fluorescence of a highly conserved tryptophan residue that constitutes the hydrophobic pocket for GBL binding, a unique feature possessed by this family of receptors...
2018: Methods in Molecular Biology
Marc Biarnes-Carrera, Rainer Breitling, Eriko Takano
In Streptomyces, the onset of antibiotic production and sporulation is coordinated through small diffusible molecules known as γ-butyrolactones (GBLs). These are active in very low amounts, and their extraction and characterization are challenging. Here we describe a rapid, small-scale method for the extraction of GBL from Streptomyces coelicolor, from both solid and liquid cultures, which provides sufficient material for subsequent bioassays and partial characterization. We also present two different bioassay techniques for the detection and quantification of the GBL content in the extracts: the antibiotic bioassay and the kanamycin bioassay...
2018: Methods in Molecular Biology
Diana Rocha, Beatriz Ruiz-Villafán, Monserrat Manzo, Romina Rodríguez-Sanoja, Sergio Sánchez
Bacterial conjugation is a powerful tool used for DNA transfer from Escherichia coli into various bacteria including streptomycetes. In this methodology, spores are usually employed as recipient cells of the genetic information. However, some industrially important Streptomyces do not produce spores making difficult their genetic manipulation. In these strains, the use of mechanically fragmented mycelia allows DNA transfer with low efficiency. Streptomyces peucetius var. caesius is a non-sporulating bacteria which produces the antitumor compound doxorubicin...
November 7, 2017: Journal of Microbiological Methods
Mark J Buttner, Martin Schäfer, David M Lawson, Anthony Maxwell
Simocyclinones are antibiotics produced by Streptomyces and Kitasatospora species that inhibit the validated drug target DNA gyrase in a unique way, and they are thus of therapeutic interest. Structural approaches have revealed their mode of action, the inducible-efflux mechanism in the producing organism, and given insight into one step in their biosynthesis. The crystal structures of simocyclinones bound to their target (gyrase), the transcriptional repressor SimR, and the biosynthetic enzyme SimC7 reveal fascinating insight into how molecular recognition is achieved with these three unrelated proteins...
November 8, 2017: FEMS Microbiology Reviews
Jan Rinkel, Lukas Lauterbach, Jeroen Sidney Dickschat
A terpene synthase from the marine bacterium Streptomyces xinghaiensis was characterised, including a full structure elucidation of its products from various substrates and an in-depth investigation of the enzyme mechanism by isotopic labelling experiments, substrate and metal cofactor variations, and mutation experiments. The results revealed an interesting dependency of Mn2+ catalysis on the presence of Asp-217, a residue that is occupied by a highly conserved Glu in most other bacterial terpene synthases...
November 10, 2017: Angewandte Chemie
Yang-Mei Zhang, Bai-Lian Liu, Xin-Heng Zheng, Xiao-Jun Huang, Hong-Yu Li, Ying Zhang, Ting-Ting Zhang, Da-Yuan Sun, Bi-Run Lin, Guang-Xiong Zhou
Anandins A (1) and B (2), two rare steroidal alkaloids, were isolated from the fermentative broth of a marine actinobacteria Streptomyces anandii H41-59. The gross structures of the two alkaloids were elucidated by spectroscopic methods including HR-ESI-MS, and NMR. Their absolute configurations were confirmed by single-crystal X-ray diffraction analysis and comparison of their experimental and calculated electronic circular dichroism spectra, respectively. Anandin A exhibited a moderate inhibitory effect against three human cancer cell lines MCF-7, SF-268, and NCI-H460 with IC50 values of 7...
November 10, 2017: Marine Drugs
S A Cuozzo, P E Sineli, J Davila Costa, G Tortella
Actinobacteria are well-known degraders of toxic materials that have the ability to tolerate and remove organochloride pesticides; thus, they are used for bioremediation. The biodegradation of organochlorines by actinobacteria has been demonstrated in pure and mixed cultures with the concomitant production of metabolic intermediates including γ-pentachlorocyclohexene (γ-PCCH); 1,3,4,6-tetrachloro-1,4-cyclohexadiene (1,4-TCDN); 1,2-dichlorobenzene (1,2-DCB), 1,3-dichlorobenzene (1,3-DCB), or 1,4-dichlorobenzene (1,4-DCB); 1,2,3-trichlorobenzene (1,2,3-TCB), 1,2,4-trichlorobenzene (1,2,4-TCB), or 1,3,5-trichlorobenzene (1,3,5-TCB); 1,3-DCB; and 1,2-DCB...
November 10, 2017: Critical Reviews in Biotechnology
Siti Junaidah Ahmad, Mohd Badrin Hanizam Abdul Rahim, Syarul Nataqain Baharum, Mohd Shukri Baba, Noraziah Mohamad Zin
Natural products continue to play an important role as a source of biologically active substances for the development of new drug. Streptomyces, Gram-positive bacteria which are widely distributed in nature, are one of the most popular sources of natural antibiotics. Recently, by using a bioassay-guided fractionation, an antimalarial compound, Gancidin-W, has been discovered from these bacteria. However, this classical method in identifying potentially novel bioactive compounds from the natural products requires considerable effort and is a time-consuming process...
2017: Journal of Tropical Medicine
Lanxi Su, Zongzhuan Shen, Yunze Ruan, Chengyuan Tao, Yifan Chao, Rong Li, Qirong Shen
Banana production is seriously hindered by Meloidogyne spp. all over the world. Endophytes are ideal candidates compared to pesticides as an environmentally benign agent. In the present study, endophytes isolated from banana roots infected by Meloidogyne spp. with different disease levels were tested in vitro, and in sterile and nature banana monoculture soils against Meloidogyne javanica. The proportion of antagonistic endophytes were higher in the roots of middle and high disease levels. Among those, bacteria were dominant, and Pseudomonas spp...
2017: Frontiers in Microbiology
Fernando Santos-Beneit, David M Roberts, Stuart Cantlay, Joseph R McCormick, Jeff Errington
The central player in bacterial cell division, FtsZ, is essential in almost all organisms in which it has been tested, with the most notable exception being Streptomyces. Streptomycetes differ from many bacteria in growing from the cell tip and undergoing branching, similar to filamentous fungi. Here we show that limited cell damage, either mechanical or enzymatic, leads to near complete destruction of mycelial microcolonies of a Streptomyces venezuelae ftsZ mutant. This result is consistent with a lack of ftsZ-dependent cross-walls and may be inconsistent with a recently proposed role for membrane structures in the proliferation of ftsZ mutants in other Streptomyces species...
November 9, 2017: Nature Communications
Hanxiao Ying, Jing Wang, Ting Shi, Yilei Zhao, Xin Wang, Pingkai Ouyang, Kequan Chen
Lysine cyclodeaminase (LCD) catalyzes the piperidine ring formation in macrolide-pipecolate natural products metabolic pathways from a lysine substrate through a combination of cyclization and deamination. This enzyme belongs to a unique enzyme class, which uses NAD(+) as the catalytic prosthetic group instead of as the co-substrate. To understand the molecular details of NAD(+) functions in lysine cyclodeaminase, we have determined four ternary crystal structure complexes of LCD-NAD(+) with pipecolic acid (LCD-PA), lysine (LCD-LYS), and an intermediate (LCD-INT) as ligands at 2...
November 6, 2017: Biochemical and Biophysical Research Communications
Chongxi Liu, Chuanyu Han, Shanwen Jiang, Xueli Zhao, Yuanyuan Tian, Kai Yan, Xiangjing Wang, Wensheng Xiang
During a screening for novel and biotechnologically useful actinobacteria in insects, a novel actinobacteria with antifungal activity, designated strain 5H-CA11(T), was isolated from the head of an ant (Lasius flavus) and characterized using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of members of the genus Streptomyces. 16S rRNA gene sequence analysis showed that strain 5H-CA11(T) is a member of the genus Streptomyces, with the highest sequence similarity to Streptomyces scabrisporus DSM 41855(T) (98...
November 8, 2017: Current Microbiology
Feng Xu, Jin Wang, Guo-Ping Zhao
It has been known that some Streptomyces species, including the model strain Streptomyces coelicolor, are vulnerable to visible light. Much evidence demonstrated that the phototoxicity induced by visible light is a consequence of the formation of intracellular reactive oxygen species (ROS), which are potentially harmful to cells. In this study, we found that α-ketoglutarate (α-KG) has a protective role against the phototoxicity in S. coelicolor. It could be because that α-KG can detoxify the ROS with the concomitant formation of succinate, which mediates the cells getting into anaerobiosis to produce more NADH and maintain intracellular redox homeostasis, a situation that was demonstrated by overexpressing gdhA in S...
March 2017: Biochemistry and Biophysics Reports
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