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Jie Zhou, Jia Ouyang, Qianqian Xu, Zhaojuan Zheng
The main barriers to cost-effective lactic acid production from lignocellulose are the high cost of enzymes and the ineffective utilization of the xylose within the hydrolysate. In the present study, the thermophilic Bacillus coagulans strain CC17 was used for the simultaneous saccharification and fermentation (SSF) of bagasse sulfite pulp (BSP) to produce l-lactic acid. Unexpectedly, SSF by CC17 required approximately 33.33% less fungal cellulase than did separate hydrolysis and fermentation (SHF). More interestingly, CC17 can co-ferment cellobiose and xylose without any exogenous β-glucosidase in SSF...
October 1, 2016: Bioresource Technology
Camila L Madeira, Samuel A Speet, Cristina A Nieto, Leif Abrell, Jon Chorover, Reyes Sierra-Alvarez, Jim A Field
Insensitive munitions, such as 3-nitro-1,2,4-triazol-5-one (NTO), are being considered by the U.S. Army as replacements for conventional explosives. Environmental emissions of NTO are expected to increase as its use becomes widespread; but only a few studies have considered the remediation of NTO-contaminated sites. In this study, sequential anaerobic-aerobic biodegradation of NTO was investigated in bioreactors using soil as inoculum. Batch bioassays confirmed microbial reduction of NTO under anaerobic conditions to 3-amino-1,2,4-triazol-5-one (ATO) using pyruvate as electron-donating cosubstrate...
October 14, 2016: Chemosphere
Elena Geiser, Sandra K Przybilla, Meike Engel, Wiebke Kleineberg, Linda Büttner, Eda Sarikaya, Tim den Hartog, Jürgen Klankermayer, Walter Leitner, Michael Bölker, Lars M Blank, Nick Wierckx
The Ustilaginaceae family of smut fungi, especially Ustilago maydis, gained biotechnological interest over the last years, amongst others due to its ability to naturally produce the versatile bio-based building block itaconate. Along with itaconate, U. maydis also produces 2-hydroxyparaconate. The latter was proposed to be derived from itaconate, but the underlying biochemistry and associated genes were thus far unknown. Here, we confirm that 2-hydroxyparaconate is a secondary metabolite of U. maydis and propose an extension of U...
October 14, 2016: Metabolic Engineering
Benjamin Kick, Samantha Hensler, Florian Praetorius, Hendrik Dietz, Dirk Weuster-Botz
The bacteriophage M13 has found frequent applications in nanobiotechnology due to its chemically and genetically tunable protein surface and its ability to self-assemble into colloidal membranes. Additionally, its single-stranded (ss) genome is commonly used as scaffold for DNA origami. Despite the manifold uses of M13, upstream production methods for phage and scaffold ssDNA are underexamined with respect to future industrial usage. Here, the high-cell-density phage production with Escherichia coli as host organism was studied in respect of medium composition, infection time, multiplicity of infection and specific growth rate...
October 17, 2016: Biotechnology and Bioengineering
Jeong Wook Lee, Jongho Yi, Tae Yong Kim, Sol Choi, Jung Ho Ahn, Hyohak Song, Moon-Hee Lee, Sang Yup Lee
Succinic acid (SA) is a four carbon dicarboxylic acid of great industrial interest that can be produced by microbial fermentation. Here we report development of a high-yield homo-SA producing Mannheimia succiniciproducens strain by metabolic engineering. The PALFK strain (ldhA(-), pta(-), ackA(-), fruA(-)) was developed based on optimization of carbon flux towards SA production while minimizing byproducts formation through the integrated application of in silico genome-scale metabolic flux analysis, omics analyses, and reconstruction of central carbon metabolism...
October 13, 2016: Metabolic Engineering
Said Al Hamimi, Lovisa Heyman-Lindén, Merichel Plaza, Charlotta Turner, Karin Berger, Peter Spégel
SCOPE: Lingonberries have been shown to reduce the detrimental effects of high fat diet (HFD) on weight gain, plasma glucose and inflammation. However, the extent of effects was recently shown to vary between different batches of berries. Here we examine the metabolic response to two independent batches of lingonberries. METHODS AND RESULTS: Alterations in the phenotype and circulating metabolome elicited by three matched HFDs, two of which containing lingonberries (L1D and L2D) from different sources, were investigated...
October 14, 2016: Molecular Nutrition & Food Research
Yingmiao Liu, Junzhi Wang, Chongmao Xu, Yong Chen, Junjie Yang, Dong Liu, Huanqing Niu, Yu Jiang, Sheng Yang, Hanjie Ying
Cytidine diphosphate choline (CDP-choline) has been applied for treating acute craniocerebral injury and allowing recovery of consciousness after brain surgery. In this study, an acetate kinase (ACK)/acetyl phosphate system was used to supply ATP and combined with Escherichia coli-overexpressed CMP kinase (CMK), NDP kinase (NDK), choline phosphate cytidylyltransferase (CCT), and choline kinase (CKI) to produce CDP-choline from CMP and choline chloride. Within 1 h, 49 mM CDP-choline was produced, for a molar yield of 89...
October 13, 2016: Applied Microbiology and Biotechnology
Eun Jae Kim, Jun Hyuck Lee, Sung Gu Lee, Se Jong Han
To survive in a sub-zero environment, polar organisms produce ice-binding proteins (IBPs). These IBPs prevent the formation of large intracellular ice crystals, which may be fatal to the organism. Recently, a recombinant FfIBP (an IBP from Flavobacterium frigoris PS1) was cloned and produced in Pichia pastoris using fed-batch fermentation with methanol feeding. In this study, we demonstrate that FfIBP produced by P. pastoris has a glycosylation site, which diminishes the thermal hysteresis (TH) activity of FfIBP...
October 13, 2016: Preparative Biochemistry & Biotechnology
K Divakar, M Suryia Prabha, G Nandhinidevi, Pennathur Gautam
The simultaneous production of intracellular esterase and extracellular protease from the strain Lysinibacillus fusiformis AU01 was studied in detail. The production was carried out both under batch and fedbatch mode. The maximum yield of intracellular esterase and protease was obtained under full oxygen saturation at the beginning of the fermentation. The data was fitted to the Luedeking-Piret model and it was shown that the enzyme (both esterase and protease) production was growth-associated. A decrease in intracellular esterase and increase in the extracellular esterase was observed during late stationary phase...
October 13, 2016: Preparative Biochemistry & Biotechnology
Jilong Wang, Suthamat Niyompanich, Yi-Shu Tai, Jingyu Wang, Wenqin Bai, Prithviraj Mahida, Tuo Gao, Kechun Zhang
: Chromosomal integration of heterologous metabolic pathways is optimal for industrially relevant fermentation, as plasmid-based fermentation causes extra metabolic burden and genetic instabilities. In this work, chromosomal integration was adapted for the production of mevalonate which can be readily converted into β-methyl-δ-valerolactone, a monomer for the production of mechanically tunable polyesters. The mevalonate pathway driven by a constitutive promoter was integrated into the chromosome of Escherichia coli to replace the native fermentation gene adhE or ldhA The engineered strains (CMEV-1 and CMEV-2) did not require inducer or antibiotic, and showed slightly higher maximal productivities (0...
October 7, 2016: Applied and Environmental Microbiology
Jianjun Pei, Ping Dong, Tao Wu, Linguo Zhao, Xianying Fang, Fuliang Cao, Feng Tang, Yongde Yue
Astragalin (kaempferol 3-O-glucoside) is used as a standard to assess the quality of Radix Astragali and has exhibited a number of biological properties. In this work, we screened several UDP-dependent glycosyltransferases (UGT) for their potential as efficient biocatalysts for astragalin synthesis. The highest astragalin production with 285 mg/L was detected in the recombinant strain expressing UGT from Arabidopis thaliana (AtUGT78D2). To further improve astragalin production, an efficient UDP-glucose synthesis pathway was reconstructed in the recombinant strain by introducing sucrose permease, sucrose phosphorylase and uridylyltransferase...
October 12, 2016: Journal of Agricultural and Food Chemistry
Yue Yuan, Jinjin Liu, Bin Ma, Ye Liu, Bo Wang, Yongzhen Peng
This study presents a novel strategy to improve the removal efficiency of nitrogen and phosphorus from municipal wastewater by feeding sequencing batch reactor (SBR) with sludge alkaline fermentation products as carbon sources. The performances of two SBRs treating municipal wastewater (one was fed with sludge fermentation products; F-SBR, and the other without sludge fermentation products; B-SBR) were compared. The removal efficiencies of total nitrogen (TN) and phosphorus (PO4(3-)-P) were found to be 82.9% and 96...
October 8, 2016: Bioresource Technology
Xin Wen, Jian Zhou, Yancheng Li, Xiaoxia Qing, Qiang He
In this study, a novel process combined simultaneous partial nitrification, anammox and denitrification (SNAD) with denitrifying phosphorus removal (DPR) was proposed for advanced nitrogen removal. Firstly simulating sewage was introduced to a sequencing batch reactor (SBR) for organic matter removal and anaerobic phosphorus release (stage 1). Then effluent of stage 1 with low COD was discharged to a sequencing biofilm batch reactor (SBBR) for partial nitrification, anammox and partial denitrification (stage 2)...
October 5, 2016: Bioresource Technology
A Rugor, M Tataruch, J Staroń, A Dudzik, E Niedzialkowska, P Nowak, A Hogendorf, A Michalik-Zym, D B Napruszewska, A Jarzębski, K Szymańska, W Białas, M Szaleniec
Steroid C25 dehydrogenase (S25DH) from Sterolibacterium denitrificans Chol-1S is a molybdenum oxidoreductase belonging to the so-called ethylbenzene dehydrogenase (EBDH)-like subclass of DMSO reductases capable of the regioselective hydroxylation of cholesterol or cholecalciferol to 25-hydroxy products. Both products are important biologically active molecules: 25-hydroxycholesterol is responsible for a complex regulatory function in the immunological system, while 25-hydroxycholecalciferol (calcifediol) is the activated form of vitamin D3 used in the treatment of rickets and other calcium disorders...
October 11, 2016: Applied Microbiology and Biotechnology
Stephanie Karmann, Stéphanie Follonier, Monica Bassas-Galia, Sven Panke, Manfred Zinn
Poly(3-hydroxyalkanoates) (PHAs) are bio-based and biodegradable polyesters which have been considered as a promising alternative to petrol-based plastics. Its bacterial production is a dynamic process in which intracellular polymerization and depolymerization are closely linked and depend on the availability of carbon substrates and other nutrients. These dynamics require a fast and quantitative method to determine the optimal harvest-time of PHA containing cells or to adjust carbon supply. In principle, flow cytometry (FCM) is an ideal tool that suits these requirements and, in addition, provides data on the PHA content of different cell populations...
October 6, 2016: Journal of Microbiological Methods
Rodrigo S Raposo, M Catarina M D de Almeida, M da Conceição M A de Oliveira, M Manuela R da Fonseca, M Teresa Cesário
Efficient production of poly-3-hydroxybutyrate (P(3HB)) based on glucose-xylose mixtures simulating different types of lignocellulosic hydrolysate (LCH) was addressed using Burkholderia sacchari, a wild strain capable of metabolizing both sugars and producing P(3HB). Carbon catabolite repression was avoided by maintaining glucose concentration below 10g/L. Xylose concentrations above 30g/L were inhibitory for growth and production. In fed-batch cultivations, pulse size and feed addition rate were controlled in order to reach high productivities and efficient sugar consumptions...
October 5, 2016: New Biotechnology
Jianzhong Xu, Junlan Zhang, Dongdong Liu, Weiguo Zhang
The phosphoenolpyruvate:glucose phosphotransferase system (PTS(Glc)) is the major pathway of glucose uptake in Corynebacterium glutamicum. This study investigated glucose consumption rate, cell growth, and metabolite changes resulting from modification of PTS(Glc). The classical l-lysine producer C. glutamicum XQ-8 exhibited low glucose consumption, cell growth, and l-lysine production rates, whereas these parameters were significantly increased during cultivating on glucose plus maltose, through inactivation of SugR, or by overexpression of PTS(Glc) genes...
July 15, 2016: Canadian Journal of Microbiology
Junfeng Wang, Xinshan Song, Yuhui Wang, Befkadu Abayneh, Yi Ding, Denghua Yan, Junhong Bai
The microbial fuel cell coupled with constructed wetland (CW-MFC) microcosms were operated under fed-batch mode for evaluating the effect of electrode materials on bioelectricity generation and microbial community composition. Experimental results indicated that the bioenergy output in CW-MFC increased with the substrate concentration; maximum average voltage (177mV) was observed in CW-MFC with carbon fiber felt (CFF). In addition, the four different materials resulted in the formation of significantly different microbial community distribution around the anode electrode...
December 2016: Bioresource Technology
Jae Ho Shin, Seok Hyun Park, Young Hoon Oh, Jae Woong Choi, Moon Hee Lee, Jae Sung Cho, Ki Jun Jeong, Jeong Chan Joo, James Yu, Si Jae Park, Sang Yup Lee
BACKGROUND: 5-Aminovaleric acid (5AVA) is an important five-carbon platform chemical that can be used for the synthesis of polymers and other chemicals of industrial interest. Enzymatic conversion of L-lysine to 5AVA has been achieved by employing lysine 2-monooxygenase encoded by the davB gene and 5-aminovaleramidase encoded by the davA gene. Additionally, a recombinant Escherichia coli strain expressing the davB and davA genes has been developed for bioconversion of L-lysine to 5AVA...
October 7, 2016: Microbial Cell Factories
Harvey Milquez-Sanabria, Luis Blanco-Cocom, Liliana Alzate-Gaviria
BACKGROUND: Agro-industrial wastes are an energy source for different industries. However, its application has not reached small industries. Previous and current research activities performed on the acidogenic phase of two-phase anaerobic digestion processes deal particularly with process optimization of the acid-phase reactors operating with a wide variety of substrates, both soluble and complex in nature. Mathematical models for anaerobic digestion have been developed to understand and improve the efficient operation of the process...
October 3, 2016: Microbial Cell Factories
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