bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved galactose fermentation of Saccharomyces cerevisiae through inverse metabolic engineering
Authors: Lee Ki‐Sung , Hong Min‐Eui , Jung Suk‐Chae , Ha Suk‐Jin , Yu Byung Jo , Koo Hyun Min , Park Sung Min , Seo Jin‐Ho , Kweon Dae‐Hyuk , Park Jae Chan , Jin Yong‐Su 
Published: October 2010

AbstractAlthough Saccharomyces cerevisiae is capable of fermenting galactose into ethanol, ethanol yield and productivity from galactose are significantly lower than those from glucose. An inverse metabolic engineering approach was undertaken to improve ethanol yield and productivity from galactose in S. cerevisiae. A genome‐wide perturbation library was introduced into S. cerevisiae, and then fast galactose‐fermenting transformants were screened using three different enrichment methods. The characterization of genetic perturbations in the isolated transformants revealed three target genes whose overexpression elicited enhanced galactose utilization. One confirmatory (SEC53 coding for phosphomannomutase) and two novel targets (SNR84 coding for a small nuclear RNA and a truncated form of TUP1 coding for a general repressor of transcription) were identified as overexpression targets that potentially improve galactose fermentation. Beneficial effects of overexpression of SEC53 may be similar to the mechanisms exerted by overexpression of PGM2 coding for phosphoglucomutase. While the mechanism is largely unknown, overexpression of SNR84, improved both growth and ethanol production from galactose. The most remarkable improvement of galactose fermentation was achieved by overexpression of the truncated TUP1 (tTUP1) gene, resulting in unrivalled galactose fermentation capability, that is 250% higher in both galactose consumption rate and ethanol productivity compared to the control strain. Moreover, the overexpression of tTUP1 significantly shortened lag periods that occurs when substrate is changed from glucose to galactose. Based on these results we proposed a hypothesis that the mutant Tup1 without C‐terminal repression domain might bring in earlier and higher expression of GAL genes through partial alleviation of glucose repression. mRNA levels of GAL genes (GAL1, GAL4, and GAL80) indeed increased upon overexpression of tTUP. The results presented in this study illustrate that alteration of global regulatory networks through overexpression of the identified targets (SNR84 and tTUP1) is as effective as overexpression of a rate limiting metabolic gene (PGM2) in the galactose assimilation pathway for efficient galactose fermentation in S. cerevisiae. In addition, these results will be industrially useful in the biofuels area as galactose is one of the abundant sugars in marine plant biomass such as red seaweed as well as cheese whey and molasses. Biotechnol. Bioeng. 2011; 108:621–631. © 2010 Wiley Periodicals, Inc.
Engineering butanol‐tolerance in escherichia coli with artificial transcription factor libraries
Authors: Lee Ju Young , Yang Kyung Seok , Jang Su A , Sung Bong Hyun , Kim Sun Chang 
Published: October 2010

AbstractEscherichia coli has been explored as a host for butanol production because of its many advantages such as a fast growth and easy genetic manipulation. Butanol toxicity, however, is a major concern in the biobutanol production with E. coli. In particular, E. coli growth is severely inhibited by butanol, being almost completely stopped by 1% (vol/vol) butanol. Here we developed a new method to increase the butanol‐tolerance of E. coli with artificial transcription factor (ATF) libraries which consist of zinc finger (ZF) DNA‐binding proteins and an E. coli cyclic AMP receptor protein (CRP). Using these ATFs, we selected a butanol‐tolerant E. coli which can tolerate up to 1.5% (vol/vol) butanol, with a concomitant increase in heat resistance. We also identified genes of E. coli that are associated with the butanol‐tolerance. These results show that E. coli can be engineered as a promising host for high‐yield butanol production. Biotechnol. Bioeng. 2011; 108:742–749. © 2010 Wiley Periodicals, Inc.
Ectopic expression of human mTOR increases viability, robustness, cell size, proliferation, and antibody production of chinese hamster ovary cells
Authors: Dreesen Imke A.J. , Fussenegger Martin 
Published: October 2010

AbstractEngineering of mammalian production cell lines to improve titer and quality of biopharmaceuticals is a top priority of the biopharmaceutical manufacturing industry providing protein therapeutics to patients worldwide. While many engineering strategies have been successful in the past decade they were often based on the over‐expression of a single transgene and therefore limited to addressing a single bottleneck in the cell's production capacity. We provide evidence that ectopic expression of the global metabolic sensor and processing protein mammalian target of rapamycin (mTOR), simultaneously improves key bioprocess‐relevant characteristics of Chinese hamster ovary (CHO) cell‐derived production cell lines such as cell growth (increased cell size and protein content), proliferation (increased cell‐cycle progression), viability (decreased apoptosis), robustness (decreased sensitivity to sub‐optimal growth factor and oxygen supplies) and specific productivity of secreted human glycoproteins. Cultivation of mTOR‐transgenic CHO‐derived cell lines engineered for secretion of a therapeutic IgG resulted in antibody titers of up to 50 pg/cell/day, which represents a four‐fold increase compared to the parental production cell line. mTOR‐based engineering of mammalian production cell lines may therefore have a promising future in biopharmaceutical manufacturing of human therapeutic proteins. Biotechnol. Bioeng. 2011; 108:853–866. © 2010 Wiley Periodicals, Inc.
Purification of singly PEGylated α‐lactalbumin using charged ultrafiltration membranes
Authors: Ruanjaikaen Krisada , Zydney Andrew L. 
Published: October 2010

AbstractOne of the challenges in producing a PEGylated therapeutic protein is that the PEGylation reaction typically generates a mixture of both singly and multiply PEGylated species. The objective of this study was to examine the feasibility of using ultrafiltration for the purification of a singly PEGylated protein from the multiply PEGylated conjugates. Data were obtained with α‐lactalbumin that was PEGylated with a 20 kDa activated PEG, with the ultrafiltration performed over a range of pH and ionic strength using both unmodified and negatively charged composite regenerated cellulose membranes. Purification of the singly PEGylated α‐lactalbumin from the multiply PEGylated species was accomplished using a diafiltration process with a negatively charged membrane at pH 5 and an ionic strength of 0.4 mM, conditions that maximized the electrostatic exclusion of the multiply PEGylated species from the charged membrane. The diafiltration process provided more than 97% yield with greater than 20‐fold purification between the singly and doubly PEGylated proteins and nearly complete removal of the more heavily PEGylated species. The singly PEGylated α‐lactalbumin was recovered as a dilute filtrate solution, although this dilution could be eliminated using a cascade filtration or the final product could be re‐concentrated in a second ultrafiltration as part of the final formulation. These results demonstrate the feasibility of using ultrafiltration for the purification of singly PEGylated protein therapeutics. Biotechnol. Bioeng. 2011; 108:822–829. © 2010 Wiley Periodicals, Inc.
Enantiomeric separation of d,l‐tryptophan and d,l‐kynurenine by HPLC using pre‐column fluorescence derivatization with R(−)‐DBD‐PyNCS
Authors: Iizuka Hideaki , Hirasa Yasushi , Kubo Kazumi , Ishii Kana , Toyo'oka Toshimasa , Fukushima Takeshi 
Published: October 2010

AbstractThe enantiomeric separation of d,l‐tryptophan (Trp) and d,l‐kynurenine (KYN) was investigated by high‐performance liquid chromatography using pre‐column fluorescence derivatization with a chiral fluorescent labeling reagent, R(−)‐4‐(3‐isothiocyanatopyrrolidin‐1‐yl)‐7‐ (N,N‐dimethylaminosulfonyl)‐2,1,3‐benzoxadiazole [R(−)‐DBD‐PyNCS]. Using an octadecylsilica column, namely, an Inertsil ODS‐3 column (250 × 2.0 mm; i.d., 3 µm), four fluorescence peaks of D‐ and l‐Trp as well as d‐ and l‐KYN derivatized with R(−)‐DBD‐PyNCS were clearly observed, and their chemical structures were confirmed by HPLC–time‐of‐flight–mass spectrometry. Simultaneous separation was achieved under the mobile phase condition of 1.5% acetic acid in H2O–CH3CN (60:40), and the separation factors of d,l‐Trp and d,l‐KYN derivatized with R(−)‐DBD‐PyNCS were 1.22 and 1.19, respectively. Fluorescence detection was carried out by setting the emission wavelength at 565 nm, and the excitation wavelength at 440 nm, and the detection limits were approximately 0.3–0.5 pmol (signal‐to‐noise ratio of 3). Copyright © 2010 John Wiley & Sons, Ltd.
Location of the motor entry point and intramuscular motor point of the tibialis posterior muscle: For effective motor point block
Authors: Lee Je‐Hun , Lee Be‐Na , An Xiaochun , Chung Rak‐Hee , Han Seung‐Ho 
Published: October 2010

AbstractThe aim of this study was to elucidate the anatomical location of the motor entry point (MEP) and intramuscular motor point (IMP) of the tibialis posterior muscle for effective motor point block. Thirty‐six fresh specimens from 20 adult Korean cadavers (11 males and 9 females) were investigated. The reference line between the most proximal‐medial articular margin of the tibia (MPM) at the level of the knee joint and the most distal point of the malleolus of the tibia (MDM) on the surface were identified. The mean length of the reference line was 326.5 ± 27.1 mm. There were 82.5% of the total number of MEPs located at 10–30% and 67.9% of the total IMPs were 10–40% from the MPM. The safety zone for botulinum toxin (BTX) injections on the medial approach was 10–40% from the MPM. In addition, insertion of the needle to a depth of 3.5 cm from the surface of the skin was effective. These results may assist in determining more accurate localization of injection sites. Clin. Anat. 24:91–96, 2011. © 2011 Wiley‐Liss, Inc.
Sesamoid and accessory bones of the hand—An epidemiologic survey in a Mediterranean population
Authors: Amar Eyal , Rozenblat Yishai , Chechik Ofir 
Published: October 2010

AbstractThe prevalence and distribution of sesamoid and accessory bones in the hands is quite variable between different populations and ethnic groups. However, there are no published data on their distribution in Mediterranean populations. Studies on the validity of radiographic assessment for the presence of these bones are also lacking. A retrospective review of 442 radiographs of adult patients was performed in order to assess the incidence of sesamoid and accessory bones in the hands of a Mediterranean population. Additionally, two independent observers reviewed 174 radiographs and used the Kappa parameter in order to assess the validity of radiographic interpretation of radiographs for the presence of those bones. There was an incidence of 99.5% sesamoid bones (n = 440) in the 1st metacarpophalangeal (MCP) joint, 42.3% in the 2nd MCP joint (n = 187), and 41.1% (n = 182) in the 5th MCP joint. The incidence in the 1st interphalangeal joints was 26.2% (n = 116). The incidence of sesamoid bones in the 1st, 2nd, and 5th metacarpophalangeal joints in a Mediterranean population was found to be similar to that of Arab and Caucasian populations, whereas their prevalence in the 1st interphalageal joint coincided more with Arab populations. Interobserver reliability of the interpretation of radiographs for the presence of sesamoid bones in the hand was good (Kappa > 0.68) in all locations, except for the 1st MCP joint. Further research is warranted to further elucidate the genetic and/or environmental reasons for the differences between those populations. Clin. Anat. 24:183–187, 2011. © 2010 Wiley‐Liss, Inc.
Alpha‐lipoic acid does not alter stress protein response to acute exercise in diabetic brain
Authors: Lappalainen Jani , Lappalainen Zekine , Oksala Niku K. J. , Laaksonen David E. , Khanna Savita , Sen Chandan K. , Atalay Mustafa 
Published: October 2010

AbstractHeat shock proteins (HSPs) are molecular chaperones which may act protective in cerebrovascular insults and peripheral diabetic neuropathy. We hypothesized that alpha‐lipoic acid (LA), a natural thiol antioxidant, may enhance brain HSP response in diabetes. Rats with or without streptozotocin‐induced diabetes were treated with LA or saline for 8 weeks. Half of the rats were subjected to exhaustive exercise to investigate HSP induction, and the brain tissue was analyzed. Diabetes increased constitutive HSC70 mRNA, and decreased HSP90 and glucose‐regulated protein 75 (GRP75) mRNA without affecting protein levels. Exercise increased HSP90 protein and mRNA, and also GRP75 and heme oxygenase‐1 (HO‐1) mRNA only in non‐diabetic animals. LA had no significant effect on brain HSPs, although LA increased HSC70 and HO‐1 mRNA in diabetic animals and decreased HSC70 mRNA in non‐diabetic animals. Eukaryotic translation elongation factor‐2, essential for protein synthesis, was decreased by diabetes and suggesting a mechanism for the impaired HSP response related to translocation of the nascent chain during protein synthesis. LA supplementation does not offset the adverse effects of diabetes on brain HSP mRNA expression. Diabetes may impair HSP translation through elongation factors related to nascent chain translocation and subsequent responses to acute stress. Copyright © 2010 John Wiley & Sons, Ltd.
A Strategy for Designing a Peptide Probe for Detection of β‐Amyloid Oligomers
Authors: Hu Yang , Su Baihao , Kim Chung‐Sei , Hernandez Michael , Rostagno Agueda , Ghiso Jorge , Kim Jin Ryoun 
Published: October 2010

AbstractAggregation of β‐amyloid (Aβ) is implicated in the pathology of Alzheimer's disease. Development of a robust strategy to detect Aβ oligomeric intermediates, which have been identified as significant toxic agents, would be highly beneficial in the screening of drug candidates as well as enhancing our understanding of Aβ oligomerization. Rapid, specific and quantitative detection, currently unavailable, would be highly preferred for accurate and reliable probing of transient Aβ oligomers. Here, we report the development of a novel peptide probe, PG46, based on the nature of Aβ self‐assembly and the conformation‐sensitive fluorescence of the biarsenical dye, FlAsH. PG46 was found to bind to Aβ oligomers and displayed an increase in FlAsH fluorescence upon binding. No such event was observed when PG46 was co‐incubated with Aβ low‐molecular‐weight species or Aβ fibrils. Aβ oligomer detection was fast, and occurred within one hour without any additional sample incubation or preparation. We anticipate that the development of a strategy for detection of amyloid oligomers described in this study will be directly relevant to a host of other amyloidogenic proteins.
Mechanism(s) of SWI/SNF‐Induced Nucleosome Mobilization
Authors: Liu Ning , Balliano Angela , Hayes Jeffrey J. 
Published: October 2010

AbstractImpediments to DNA access due to assembly of the eukaryotic genome into chromatin are in part overcome by the activity of ATP‐dependent chromatin‐remodeling complexes. These complexes employ energy derived from ATP hydrolysis to destabilize histone—DNA interactions and alter nucleosome positions, thereby increasing the accessibility of DNA‐binding factors to their targets. However, the mechanism by which theses complexes accomplish this task remains unresolved. We review aspects of nucleosome alteration by the SWI/SNF complex, the archetypal remodeling enzyme. We focus on experiments that provide insights into how SWI/SNF induces nucleosome movement along DNA. Numerous biochemical activities have been characterized for this complex, all likely providing clues as to the molecular mechanism of translocation.
Controlled Synthesis of a Thin LTL Zeolitic Membrane Using Nano‐Sized Seeds: Characterization and Permeation Performance
Authors: Ghoroghchian F. , Aghabozorg H. , Farhadi F. , Kazemian H. 
Published: October 2010

AbstractIndustrial zeolitic membranes which offer a remarkable selectivity compared to polymeric membranes, suffer of the lower flux due of their larger thickness (e.g., 10–30 μm). This problem can be addressed by controlled synthesis of nanolayers, resulting in thinner membrane layers (e.g., 0.5–5 μm). An aluminosilicate gel with a molar composition of 20SiO2:Al2O3:10K2O:400H2O was used to prepare several membranes of zeolite L by means of a controlled hydrothermal synthesis on the surface of a porous alumina disc seeded with nanozeolite LTL crystals. Nanocrystallites of LTL zeolite with an average particle size of 80–100 nm were successfully synthesized and characterized. Using these nanoparticles as seeds, a zeolite L layer with an average thickness of 2 μm was synthesized on the alumina support at 150 °C.
Analysis of a pH‐Based Potentiometric Biosensor Using the Homotopy Perturbation Method
Authors: Meena A. , Rajendran L. 
Published: October 2010

AbstractA mathematical model of steady‐state and non‐steady‐state responses of a pH‐based potentiometric biosensor immobilizing organophosphorus hydrolase was developed. The model is based on non‐stationary diffusion equations containing a nonlinear term related to the Michaelis‐Menten kinetics of an enzymatic reaction. An analytical expression for the substrate concentration was obtained for all values of parameter a (Thiele modulus) using the homotopy perturbation method. From this result, the concentrations of the deprotonation products of an organophosphodiester (PhH, ZH and AH) were obtained. Our analytical results were compared with available simulation results. A satisfactory agreement with the simulation data is noted.
Catalytic Steam Reforming of Fast Pyrolysis Bio‐Oil in Fixed Bed and Fluidized Bed Reactors
Authors: Lan P. , Xu Q. , Zhou M. , Lan L. , Zhang S. , Yan Y. 
Published: October 2010

AbstractCatalytic steam reforming of bio‐oil is an economically‐feasible route which produces renewable hydrogen. The Ni/MgO‐La2O3‐Al2O3 catalyst was prepared with Ni as active agent, Al2O3 as support, and MgO and La2O3 as promoters. The experiments were conducted in fixed bed and fluidized bed reactors, respectively. Temperature, steam‐to‐carbon mole ratio (S/C), and liquid hourly space velocity (LHSV) were investigated with hydrogen yield as index. For the fluidized bed reactor, maximum hydrogen yield was obtained under temperatures 700–800 °C, S/C 15–20, LHSV 0.5–1.0 h–1, and the maximum H2 yield was 75.88 %. The carbon deposition content obtained from the fluidized bed was lower than that from the fixed bed. The maximum H2 yield obtained in the fluidized bed was 7 % higher than that of the fixed bed. The carbon deposition contents obtained from the fluidized bed was lower than that of the fixed bed at the same reaction temperature.
Ridge and PLS based rational function regression
Authors: Taavitsainen Veli‐Matti 
Published: October 2010

AbstractThis study introduces both ridge and partial least squares (PLS) regression based rational function regression techniques. The results of four different cases are compared to those obtained using other regression techniques. The results are mostly favorable, and the proposed method should be considered as a noteworthy alternative in nonlinear modeling. Copyright © 2010 John Wiley & Sons, Ltd.
New‐Phased Metastable V2O3 Porous Urchinlike Micronanostructures: Facile Synthesis and Application in Aqueous Lithium Ion Batteries
Authors: Xu Yang , Zheng Lei , Wu Changzheng , Qi Fei , Xie Yi 
Published: October 2010

AbstractNew‐phased metastable V2O3 porous urchinlike micronanostructures were first fabricated on a large scale by a simple top‐down strategy of pyrolyzing a vanadyl ethylene glycolated precursor in the absence of any templates or matrices. The pyrolysis mechanism was clearly revealed by synchrotron vacuum ultraviolet (VUV) photoionization mass spectra for the first time. The new‐phased metastable V2O3 exhibits a body‐centered cubic bixbyite structure and shows structural evolution from metastable cubic symmetry to thermodynamically stable rhombohedral symmetry V2O3 (R) above 510 °C. Furthermore, the prepared V2O3 porous urchinlike micronanostructures, as anode materials in aqueous lithium ion batteries, exhibit improved electrochemical properties with relatively high first discharge capacity and better cycle retention relative to thermodynamically stable V2O3 (R), which is derived from its unique microscopic crystal structure and macroscopic 3D framework with rigid morphology, porous structure, and high specific surface area.
A Photoelectrochemical Immunosensor Based on Au‐Doped TiO2 Nanotube Arrays for the Detection of α‐Synuclein
Authors: An Yarui , Tang Linlin , Jiang Xiaoli , Chen Hua , Yang Meicheng , Jin Litong , Zhang Shengping , Wang Chuangui , Zhang Wen 
Published: October 2010

Abstractα‐Synuclein (α‐SYN) is a very important neuronal protein that is associated with Parkinson’s disease. In this paper, we utilized Au‐doped TiO2 nanotube arrays to design a photoelectrochemical immunosensor for the detection of α‐SYN. The highly ordered TiO2 nanotubes were fabricated by using an electrochemical anodization technique on pure Ti foil. After that, a photoelectrochemical deposition method was exploited to modify the resulting nanotubes with Au nanoparticles, which have been demonstrated to facilitate the improvement of photocurrent responses. Moreover, the Au‐doped TiO2 nanotubes formed effective antibody immobilization arrays and immobilized primary antibodies (Ab1) with high stability and bioactivity to bind target α‐SYN. The enhanced sensitivity was obtained by using {Ab2‐Au‐GOx} bioconjugates, which featured secondary antibody (Ab2) and glucose oxidase (GOx) labels linked to Au nanoparticles for signal amplification. The GOx enzyme immobilized on the prepared immunosensor could catalyze glucose in the detection solution to produce H2O2, which acted as a sacrificial electron donor to scavenge the photogenerated holes in the valence band of TiO2 nanotubes upon irradiation of the other side of the Ti foil and led to a prompt photocurrent. The photocurrents were proportional to the α‐SYN concentrations, and the linear range of the developed immunosensor was from 50 pg mL−1 to 100 ng mL−1 with a detection limit of 34 pg mL−1. The proposed method showed high sensitivity, stability, reproducibility, and could become a promising technique for protein detection.