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1.
Objectives
To improve the quality of diesel fuel via removal of aromatic compounds using Pseudomonas sp.Results
In the present study Pseudomonas sp. was able to remove 94% of fluorene, 59% of phenanthrene, 49% of anthracene, 52% of fluoranthene, 45% of pyrene and 75% carbazole present in diesel oil. Additionally, it also does not affect the aliphatic content of fuel thus maintaining the carbon backbone of the fuel.Conclusions
Pseudomonas sp. is a potential biocatalyst that can be used in the refining industry.2.
Background
The thermophilic anaerobe Thermoanaerobacterium saccharolyticum is capable of directly fermenting xylan and the biomass-derived sugars glucose, cellobiose, xylose, mannose, galactose and arabinose. It has been metabolically engineered and developed as a biocatalyst for the production of ethanol.Results
We report the initial characterization of the carbon catabolite repression system in this organism. We find that sugar metabolism in T. saccharolyticum is regulated by histidine-containing protein HPr. We describe a mutation in HPr, His15Asp, that leads to derepression of less-favored carbon source utilization.Conclusion
Co-utilization of sugars can be achieved by mutation of HPr in T. saccharolyticum. Further manipulation of CCR in this organism will be instrumental in achieving complete and rapid conversion of all available sugars to ethanol.3.
Korey J. Brownstein Mahmoud Gargouri William R. Folk David R. Gang 《Metabolomics : Official journal of the Metabolomic Society》2017,13(11):133
Introduction
Botanicals containing iridoid and phenylethanoid/phenylpropanoid glycosides are used worldwide for the treatment of inflammatory musculoskeletal conditions that are primary causes of human years lived with disability, such as arthritis and lower back pain.Objectives
We report the analysis of candidate anti-inflammatory metabolites of several endemic Scrophularia species and Verbascum thapsus used medicinally by peoples of North America.Methods
Leaves, stems, and roots were analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and partial least squares-discriminant analysis (PLS-DA) was performed in MetaboAnalyst 3.0 after processing the datasets in Progenesis QI.Results
Comparison of the datasets revealed significant and differential accumulation of iridoid and phenylethanoid/phenylpropanoid glycosides in the tissues of the endemic Scrophularia species and Verbascum thapsus.Conclusions
Our investigation identified several species of pharmacological interest as good sources for harpagoside and other important anti-inflammatory metabolites.4.
Nicholas J. Bond Albert Koulman Julian L. Griffin Zoe Hall 《Metabolomics : Official journal of the Metabolomic Society》2017,13(11):128
Introduction
Mass spectrometry imaging (MSI) experiments result in complex multi-dimensional datasets, which require specialist data analysis tools.Objectives
We have developed massPix—an R package for analysing and interpreting data from MSI of lipids in tissue.Methods
massPix produces single ion images, performs multivariate statistics and provides putative lipid annotations based on accurate mass matching against generated lipid libraries.Results
Classification of tissue regions with high spectral similarly can be carried out by principal components analysis (PCA) or k-means clustering.Conclusion
massPix is an open-source tool for the analysis and statistical interpretation of MSI data, and is particularly useful for lipidomics applications.5.
Wenyuan Gao Haiyang Fan Lifeng Chen Hualei Wang Dongzhi Wei 《Biotechnology letters》2016,38(7):1165-1171
Objective
To identify an esterase-mediated kinetic resolution of secondary alcohols in non-aqueous medium.Results
An esterase, EST4, from a marine mud metagenomic library, showed high activity and enantioselectivity for the kinetic resolution of secondary alcohols in non-aqueous medium. Using 1-phenylethanol as the model alcohol, the effects of organic solvents, acyl donors, molar ratio, temperatures and biocatalyst loading on the kinetic resolution catalyzed by the EST4 whole-cell biocatalyst were investigated and optimized. The optimized methodology was effective on resolving 16 various racemic secondary alcohols in neat n-hexane, providing excellent enantiomeric excess (up to 99.9 % ee). Moreover, EST4 exhibited a strong tolerance for high substrate concentration (up to 1 M), and the optical purity of the desired secondary alcohols was kept above 99 % ee.Conclusion
The esterase EST4 is a promising biocatalyst for the enantioselective synthesis of various alcohols and esters with interesting practical applications.6.
Thijs Welle Anna T. Hoekstra Ineke A. J. J. M. Daemen Celia R. Berkers Matheus O. Costa 《Metabolomics : Official journal of the Metabolomic Society》2017,13(7):83
Introduction
Swine dysentery caused by Brachyspira hyodysenteriae is a production limiting disease in pig farming. Currently antimicrobial therapy is the only treatment and control method available.Objective
The aim of this study was to characterize the metabolic response of porcine colon explants to infection by B. hyodysenteriae.Methods
Porcine colon explants exposed to B. hyodysenteriae were analyzed for histopathological, metabolic and pro-inflammatory gene expression changes.Results
Significant epithelial necrosis, increased levels of l-citrulline and IL-1α were observed on explants infected with B. hyodysenteriae.Conclusions
The spirochete induces necrosis in vitro likely through an inflammatory process mediated by IL-1α and NO.7.
Wenwen Zhang Zhaohui Chen Mengmeng Wu Zhong Shi Feng Zhu Guoqiang li Ting Ma 《Biotechnology letters》2016,38(6):991-997
Objective
To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs.Results
The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l?1 compared to 21 g ± 0.4 g l?1 in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties.Conclusions
Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.8.
Nicole Werner Miriam Dreyer Wenke Wagner Nicolas Papon Steffen Rupp Susanne Zibek 《Biotechnology letters》2017,39(3):429-438
Objectives
To explore Candida guilliermondii for the production of long-chain dicarboxylic acids (DCA), we performed metabolic pathway engineering aiming to prevent DCA consumption during β-oxidation, but also to increase its production via the ω-oxidation pathway.Results
We identified the major β- and ω-oxidation pathway genes in C. guilliermondii and performed first steps in the strain improvement. A double pox disruption mutant was created that slowed growth with oleic acid but showed accelerated DCA degradation. Increase in DCA production was achieved by homologous overexpression of a plasmid borne cytochrome P450 monooxygenase gene.Conclusion
C. guilliermondii is a promising biocatalyst for DCA production but further insight into its fatty acid metabolism is necessary.9.
Timothy D. Leathers Joseph O. Rich Melinda S. Nunnally Amber M. Anderson 《Biotechnology letters》2018,40(1):157-163
Objective
To test the inactivation of the antibiotic, virginiamycin, by laccase-induced culture supernatants of Aureobasidium pullulans.Results
Fourteen strains of A. pullulans from phylogenetic clade 7 were tested for laccase production. Three laccase-producing strains from this group and three previously identified strains from clade 5 were compared for inactivation of virginiamycin. Laccase-induced culture supernatants from clade 7 strains were more effective at inactivation of virginiamycin, particularly at 50 °C. Clade 7 strain NRRL Y-2567 inactivated 6 µg virginiamycin/ml within 24 h. HPLC analyses indicated that virginiamycin was degraded by A. pullulans.Conclusions
A. pullulans has the potential for the bioremediation of virginiamycin-contaminated materials, such as distiller’s dry grains with solubles (DDGS) animal feed produced from corn-based fuel ethanol production.10.
Objectives
To use permeabilized cells of the fission yeast, Schizosaccharomyces pombe, that expresses human UDP-glucose 6-dehydrogenase (UGDH, EC 1.1.1.22), for the production of UDP-glucuronic acid from UDP-glucose.Results
In cell extracts no activity was detected. Therefore, cells were permeabilized with 0.3 % (v/v) Triton X-100. After washing away all low molecular weight metabolites, the permeabilized cells were directly used as whole cell biocatalyst. Substrates were 5 mM UDP-glucose and 10 mM NAD+. Divalent cations were not added to the reaction medium as they promoted UDP-glucose hydrolysis. With this reaction system 5 mM UDP-glucose were converted into 5 mM UDP-glucuronic acid within 3 h.Conclusions
Recombinant permeabilized cells of S. pombe can be used to synthesize UDP-glucuronic acid with 100 % yield and selectivity.11.
Maha M. Ismail Tamer M. Essam Yasser M. Ragab Fathia E. Mourad 《Biotechnology letters》2016,38(9):1493-1502
Objective
To test the toxicity of ketoprofen (a commonly-used NSAIDs) using two microalgal strains and Artemia sp. following the isolation of bacterial and microalgal strains and testing their ability to biodegrade and tolerate ketoprofen.Results
Chlorella sp. was the most resistant to ketoprofen. A defined bacterial consortium (K2) degraded 5 mM ketoprofen as a sole carbon source both in the dark or continuous illumination. Ketoprofen did not undergo photodegradation. In the dark, biodegradation was faster with a lag phase of 10 h, 41% COD removal and 82 % reduction in toxicity. The consortium degraded up to 16 mM ketoprofen. The consortium was composed of four bacterial isolates that were identified. MS/MS analysis suggested a ketoprofen biodegradation pathway that has not been previously reported. Combining Chlorella sp. and the K2 consortium, ketoprofen was degraded within 7 days under a diurnal cycle of 12 h light/12 h dark.Conclusion
The feasibility of using a microalgal–bacterial system to treat pharmaceutical wastewater is promising for the reduction of the process cost and providing a safer technology for pharmaceutical wastewater treatment.12.
Ying-ge Wang Jin-mei Cheng Hai-bo Ding Xi Lin Guo-hao Chen Mei Zhou Sheng-nan Ye 《Mycopathologia》2018,183(3):551-558
Objective
To improve the diagnosis and treatment of Penicilliosis marneffei without human immunodeficiency virus infection.Methods
Analyze and review the clinical features, diagnosis and treatment of six cases of P. marneffei without human immunodeficiency virus infection at The First Affiliated Hospital of Fujian Medical University.Results
Two cases were diagnosed in the ENT Department, three cases in the respiratory department and one case in the dermatological department. Penicillium marneffei infection was confirmed by sputum culture, blood culture and tissue biopsy. After definite diagnosis, one refused further treatment, and others showed significant improvement.Conclusion
Penicilliosis marneffei is insidious onset and easy to be escaped and misdiagnosed. To achieve early diagnosis and appropriate treatment, doubtful cases should be alerted for the diagnoses as P. marneffei.13.
Takuya Matsusako Yoshihiro Toya Katsunori Yoshikawa Hiroshi Shimizu 《Biotechnology for biofuels》2017,10(1):307
Background
Synechocystis sp. PCC 6803 is an attractive organism for the production of alcohols, such as isobutanol and ethanol. However, because stress against the produced alcohol is a major barrier for industrial applications, it is highly desirable to engineer organisms with strong alcohol tolerance.Results
Isobutanol-tolerant strains of Synechocystis sp. PCC 6803 were obtained by long-term passage culture experiments using medium containing 2 g/L isobutanol. These evolved strains grew on medium containing 5 g/L isobutanol on which the parental strain could not grow. Mutation analysis of the evolved strains revealed that they acquired resistance ability due to combinatorial malfunctions of slr1044 (mcpA) and slr0369 (envD), or slr0322 (hik43) and envD. The tolerant strains demonstrated stress resistance against isobutanol as well as a wide variety of alcohols such as ethanol, n-butanol, and isopentanol. As a result of introducing an ethanol-producing pathway into the evolved strain, its productivity successfully increased to 142% of the control strain.Conclusions
Novel mutations were identified that improved the stress tolerance ability of various alcohols in Synechocystis sp. PCC 6803.14.
Kyung?Min?Lee Okkyoung?Choi Ki-Yeon?Kim Han?Min?Woo Yunje?Kim Sung?Ok?Han Byoung-In?Sang Youngsoon?Um
Objective
To produce butyric acid from red algae such as Gelidium amansii in which galactose is a main carbohydrate, microorganisms utilizing galactose and tolerating inhibitors in hydrolysis including levulinic acid and 5-hydroxymethylfurfural (HMF) are required.Results
A newly isolated bacterium, Clostridium sp. S1 produced butyric acid not only from galactose as the sole carbon source but also from a mixture of galactose and glucose through simultaneous utilization. Notably, Clostridium sp. S1 produced butyric acid and a small amount of acetic acid with the butyrate:acetate ratio of 45.4:1 and it even converted acetate to butyric acid. Clostridium sp. S1 tolerated 0.5–2 g levulinic acid/l and recovered from HMF inhibition at 0.6–2.5 g/l, resulting in 85–92 % butyric acid concentration of the control culture. When acid-pretreated G. amansii hydrolysate was used, Clostridium sp. S1 produced 4.83 g butyric acid/l from 10 g galactose/l and 1 g glucose/l.Conclusion
Clostridium sp. S1 produces butyric acid from red algae due to its characteristics in sugar utilization and tolerance to inhibitors, demonstrating its advantage as a red algae-utilizing microorganism.15.
Yanping Zhou Wiktor Lisowski Yan Zhou Ng Wun Jern Kama Huang Eileen Fong 《Biotechnology letters》2017,39(10):1509-1514
Objectives
To improve its phosphate accumulating abilities for phosphate recycling from wastewater, a magnetotactic bacterium, Magnetospirillum gryphiswaldense, was genetically modified to over-express polyphosphate kinase.Results
Polyphosphate kinase was over-expressed in the bacterium. The recombinant strain accumulated ninefold more polyphosphate from synthetic wastewater compared to original wild type. The magnetic property of the recombinant M. gryphiswaldense strain was retained.Conclusions
The recombinant M. gryphiswaldense can be used for phosphate removal and recovery in bioremediation.16.
Objectives
To develop a versatile Trichoderma reesei (teleomorph Hypocrea jecorina) expression system for the high-purity production of heterologous proteins.Results
The versatile T. reesei expression system is based on xyn1 and xyn2 promoters, A824V transition in XYRI, and a bicomponent carbon source strategy. Red fluorescent protein gene rfp and alkaline endoglucanase EGV gene egv3 from Humicola insolens were used as reporter genes to test our versatile expression systemConclusions
The versatile T. reesei expression system can be applied to produce heterologous proteins with high purity and high yield.17.
Background
Marine actinomycetes are efficient producers of new secondary metabolites that show different biological activities, including antibacterial, antifungal, anticancer, insecticidal, and enzyme inhibition activities.Methods
The morphological, physiological, and biochemical properties of the strain Streptomyces sp. VITPSA were confirmed by conventional methods. Antibacterial, anti-oxidant, anti-inflammatory, anti-diabetic, and cytotoxic activities of Streptomyces sp. VITPSA extract were determined. The media were optimized for the production of secondary metabolites. Characterization and identification of secondary metabolites were conducted by high-performance liquid chromatography, gas chromatography-mass spectroscopy, and Fourier transform infrared spectroscopy analysis.Results
The strain showed significant antibacterial, anti-oxidant, and cytotoxic activities, moderate anti-inflammatory activity, and no satisfactory anti-diabetic activity. The ethyl acetate extract of Streptomyces sp. VITPSA showed maximum antibacterial activity against two gram-positive and gram-negative bacteria at 0.5 mg/mL. The antioxidant potential of the crude extract exhibited strong reducing power activity at 0.5 mg/mL with 95.1% inhibition. The cytotoxic effect was found to be an IC50 of 50 μg/mL on MCF-7 cell lines. Experimental design of optimization by one-factor analysis revealed the most favorable sucrose, yeast extract, pH (7.25), and temperature (28°C) conditions for the effective production of secondary metabolites.Conclusion
This study revealed that Streptomyces sp. VITPSA is an excellent source of secondary metabolites with various bioactivities.18.
Songwen Tan Xuncai Chen Chunzhi Cui Yang Hou Weiguo Li Hong You 《Biotechnology letters》2017,39(1):91-96
Objective
To develop a method to treat saline phenolic wastewater in a biological contact oxidation reactor (BCOR) with immobilized cells of a marine microorganism, Oceanimonas sp., isolated from seawater.Results
Cells were immobilized on fibre carriers in the BCOR. Saline wastewater with phenol at 1.5 g/l and NaCl at 6 % (w/v) was treated. In continuous assays, 99 % removal of phenol was achieved and a kinetic model for the phenol degradation is presented based on Monod’s equation.Conclusion
The BOCR system using immobilized cells of Oceanimonas efficiently treats saline phenolic wastewaters without having decrease the salinity of the wastewater.19.
Junjie Zhang Chen Guo Wenfeng Chen Yimin Shang Philippe de Lajudie Xu Yang Peihong Mao Jianqiang Zheng En Tao Wang 《Plant and Soil》2018,429(1-2):241-251
Aims
Cyanobacterial and algal communities have a large effect on biocrust formation and development. Biocrust species and abundance vary spatially and temporally due to different environmental factors. The relationships among cyanobacterial and algal communities, and biocrust function have been studied extensively. Lacking, however, are studies of temporal changes in a similar landscape where environmental conditions are similar, but where biocrust formation is different.Methods
Biocrusts of different ages were located in the Loess Plateau in an area that had experienced a landslide. We examined changes in cyanobacterial and algal communities, carbon, nutrients, and the composition of dissolved organic matter in the topsoil, and the relationships among the community and soil characteristics using redundancy analysis.Results
Phormidium tenue (Cyanophyta) dominated in all biocrusts, and co-dominated in a newly formed crust with Euglena sp. (Euglenophyta). Oscillatoria sp. (Cyanophyta) increased with biocrust age. Oscillatoria was positively correlated with carbon fixation and nutrient (nitrogen and phosphorus) accumulation in topsoils.Conclusions
While incubation of Phormidium tenue and Euglena sp. is suggested for rapid biocrust formation at an early stage, increasing the abundance of Phormidium tenue and Oscillatoria sp. can promote carbon fixation and nutrient (nitrogen and phosphorus) accumulation, thereby accelerating biocrusts into a later stage.20.
Margarita Stritzler Ana Diez Tissera Gabriela Soto Nicolás Ayub 《Biotechnology letters》2018,40(9-10):1419-1423