Abstract:
:A highly active xylose specific transporter without glucose inhibition is highly desirable in cost-effective production of biofuels from lignocellulosic biomass. However, currently available xylose specific transporters suffer from low overall activity and most are inhibited by glucose. In this study, we applied a directed evolution strategy to engineer the xylose specific transporter AN25 from Neurospora crassa with improved xylose transportation capacity. After four rounds of directed evolution using two different strategies, we obtained an AN25 mutant AN25-R4.18 with 43-fold improvement in terms of xylose transportation capacity while maintaining its high xylose specificity. In addition, glucose inhibition was almost completely eliminated in the final evolved mutant. We demonstrated that improved xylose transportation of AN25 mutants in the exponential growth phase led to significant improvement of xylose consumption in high cell-density fermentation. Finally, we showed that AN25 mutant AN25-R4.18 can enable relatively efficient glucose-xylose co-utilization in high concentrations of mixed sugars.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Wang M,Yu C,Zhao Hdoi
10.1002/bit.25724subject
Has Abstractpub_date
2016-03-01 00:00:00pages
484-91issue
3eissn
0006-3592issn
1097-0290journal_volume
113pub_type
杂志文章abstract::The progression of liver disease from normal to cirrhotic state is characterized by modulation of the stiffness of the extracellular matrix (ECM). Mimicking this modulation in vitro scaffold could provide a better insight into hepatic cell behavior. In this study, interpenetrating poly(N-isopropylacrylamide-co-gelatin...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27218
更新日期:2020-02-01 00:00:00
abstract::Retroviral-derived biopharmaceuticals (RV) target numerous therapeutic applications, from gene therapy to virus-like particle (rVLP)-based vaccines. During particle formation, beside the pseudotyped envelope proteins, RV can incorporate proteins derived from the virus producer cells (VPC). This may be detrimental by r...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.23231
更新日期:2011-11-01 00:00:00
abstract::Protein glycosylation, or the attachment of sugar moieties (glycans) to proteins, is important for protein stability, activity, and immunogenicity. However, understanding the roles and regulations of site-specific glycosylation events remains a significant challenge due to several technological limitations. These limi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26502
更新日期:2018-03-01 00:00:00
abstract::Efficient xylose utilization will facilitate microbial conversion of lignocellulosic sugar mixtures into valuable products. In Escherichia coli, xylose catabolism is controlled by carbon catabolite repression (CCR). However, in E. coli such as the succinate-producing strain KJ122 with disrupted CCR, xylose utilization...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27004
更新日期:2019-08-01 00:00:00
abstract::L-Threonine, a kind of essential amino acid, has numerous applications in food, pharmaceutical, and aquaculture industries. Fermentative l-threonine production from glucose has been achieved in Escherichia coli. However, there are still several limiting factors hindering further improvement of l-threonine productivity...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26844
更新日期:2019-01-01 00:00:00
abstract::We performed a macrokinetic and quantitative microbial investigation of a continuously operating bench-scale biofilter treating styrene-polluted gases. The device was filled with a mixture of peat and glass beads as packing medium and inoculated with the styrene-oxidizing strain, Rhodococcus rhodochrous AL NCIMB 13259...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10640
更新日期:2003-07-05 00:00:00
abstract::Pulses of several nonreacting solutes were fed to a column containing immobilized enzyme catalyst beads. The response curves were recorded, and their first and second moments were determined by numerical integration. From the moment analysis, the void volume, internal porosity, and tortuosity of the support were calcu...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260250707
更新日期:1983-07-01 00:00:00
abstract::In this study, the effects of the electric charges and fields on the viability of airborne microorganisms were investigated. The electric charges of different magnitude and polarity were imparted on airborne microbial cells by a means of induction charging. The airborne microorganisms carrying different electric charg...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10290
更新日期:2002-07-20 00:00:00
abstract::In Part II, the process utility of a thermotolerant methylotrophic bacterium is evaluated with respect to its dynamic response when various substrate or nutrient pulses are imposed on it while growing under steady-state conditions in a chemostat. The pulses investigated were methanol pulses on methanol-, methanol/form...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260360811
更新日期:1990-10-20 00:00:00
abstract::Synthetic mixtures of predominant lignocellulosic hexose sugars were supplemented with separate aliquots of three inhibitory compounds (furfural, hydroxymethylfurfural (HMF), and acetic acid) in a series of concentrations and fermented by the spent sulfite liquor (SSL)-adapted yeast strain Tembec T1 and the natural is...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20838
更新日期:2006-04-20 00:00:00
abstract::The key objective for recombinant protein production in bacteria is the maximum exploitation of the cell factory's potential, whereby often strong expression vectors are used to increase product yield. If the metabolic load caused by recombinant expression exceeds the host's capacity, the system exhausts itself, resul...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10104
更新日期:2002-01-20 00:00:00
abstract::A new method is presented to precipitate proteins and amino acids from reverse micelles by dehydrating the micelles with molecular sieves. Nearly complete precipitation is demonstrated for alpha-chymotrypsin, cytochromec, and trytophan from 2-ethylhexyl sodium sulfosuccinate (AOT)/isooctane/water reverse micelle solut...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260440708
更新日期:1994-09-20 00:00:00
abstract::The possibility of biologically detoxifying a contaminated soil from an Italian dump site containing about 1500 mg/kg (in dry soil) of polychlorinated biphenyls was studied in the laboratory in this work. The soil, which contained indigenous aerobic bacteria capable of growing on biphenyl or on monochlorobenzoic acids...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19990720)64:2<240::aid-bit
更新日期:1999-07-20 00:00:00
abstract::Aryl-alcohol oxidase (AAO) plays a fundamental role in the fungal ligninolytic secretome, acting as a supplier of H2 O2 . Despite its highly selective mechanism of action, the presence of this flavooxidase in different biotechnological settings has hitherto been hampered by the lack of appropriate heterologous express...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26585
更新日期:2018-07-01 00:00:00
abstract::High throughput pretreatment (HTPH) and enzymatic hydrolysis systems are now vital for screening large numbers of biomass samples to investigate biomass recalcitrance over various pretreatment and enzymatic hydrolysis conditions. Although hydrothermal pretreatment is currently being employed in most high throughput ap...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24951
更新日期:2013-11-01 00:00:00
abstract::The specific molecular interactions of alpha-helical peptide, human glucagon (i.e., intermolecular self-association and specific receptor-binding affinity) provided a rationale for using the glucagon as the fusion expression partner to achieve high productivity of foreign proteins both in vivo (in bacterial fusion-exp...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20000820)69:4<418::aid-bit8>3.0.
更新日期:2000-08-20 00:00:00
abstract::Gene transcription is regulated by transcription factors that can bind to specific regions on DNA. Antigene oligonucleotides (oligos) can bind to specific regions on DNA and form a triplex with the double-stranded DNA. The triplex can competitively inhibit the binding of transcription factors and, as a result, transcr...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20001120)70:4<467::aid-bit13>3.0
更新日期:2000-11-20 00:00:00
abstract::Genetically transformed shooty teratomas of Atropa belladonna and a Duboisia leichhardtii x D. myoporoides hybrid were studied for biotransformation of tropane alkaloids in shake flasks and bioreactors. Although de novo synthesis of hyoscyamine and scopolamine was limited, shoots of both species were able to transloca...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960305)49:5<481::AID-BIT
更新日期:1996-03-05 00:00:00
abstract::Lipases are versatile biocatalists showing multiple applications in a wide range of biotechnological processes. The gene lipA coding for Lipase A from Bacillus subtilis was isolated by PCR amplification, cloned and expressed in Escherichia coli, Saccharomyces cerevisiae and Bacillus subtilis strains, using pBR322, YEp...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10201
更新日期:2002-05-05 00:00:00
abstract::Lentivirus-derived vectors (LVs) were studied for the generation of stable recombinant Chinese hamster ovary (CHO) cell lines. Stable pools and clones expressing the enhanced green fluorescent protein (eGFP) were selected via fluorescence-activated cell sorting (FACS). For comparison, cell pools and cell lines were al...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22968
更新日期:2011-03-01 00:00:00
abstract::Recently, the respiratory quotient (RQ) of microbes measured in situ in a fermentor by exit-gas analysis has been used successfully, for instance, in a fed-batch culture of baker's yeast as a criterion to control the feeding rate.(1-3) It is significant here to keep RQ values close to unity throughout; any deviations ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260360513
更新日期:1990-08-20 00:00:00
abstract::This article deals with the modeling of the oxygen transfer in an industrial airlift fermentor used for lactic yeast production on whey substrates. The purpose of this study was to improve the understanding of the interactions among the various parameters that govern the oxygen transfer phenomena in this type of ferme...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260390907
更新日期:1992-04-15 00:00:00
abstract::Benzil was reduced stereospecifically to (S)-benzoin by Bacillus cereus strain Tim-r01. To isolate the gene responsible for asymmetric reduction, we constructed a library consisting of Escherichia coli clones that harbored plasmids expressing Bacillus cereus genes. The library was screened using the halo formation ass...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.1191
更新日期:2001-12-20 00:00:00
abstract::In this study, white rot fungus, Polyporus brumalis, was applied to degrade dibutyl phthalate (DBP), a major environmental pollutant. The degradation potential and resulting products were evaluated with HPLC and GC/MS. As DBP concentration increased to 250, 750, and 1,250 microM, the mycelial growth of P. brumalis was...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21333
更新日期:2007-08-15 00:00:00
abstract::Microparticle-enhanced cultivation (MPEC) was applied as a novel method for improved biomass and product formation during cultivation of filamentous microorganisms. Exemplarily, chloroperoxidase (CPO) formation by Caldariomyces fumago was analyzed in the presence and absence of microparticles of different size. Partic...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21713
更新日期:2008-02-15 00:00:00
abstract::A stable Tn-5B1-4 insect cell line co-expressing the recombinant GFPuv-beta1,3-N-acetylglucosaminyltransferase 2 (GFPuv-beta3GnT2) protein fused to a melittin signal sequence with a lectin-like molecular chaperone, human calnexin (hCNX) or human calreticulin (hCRT), was constructed. The expression of either of these m...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20362
更新日期:2005-02-20 00:00:00
abstract::Increases in our understanding of gene function have greatly expanded the repertoire of possible genetic interventions at our disposal with the consequence that many genetic engineering applications require multiple manipulations in which target genes can be both overexpressed and silenced in a simple and co-ordinated...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21303
更新日期:2007-04-01 00:00:00
abstract::A kinetic model for anaerobic digestion of insoluble solid-state substrates was developed. Rate equations for cell growth and substrate consumption were derived based on the assumption that the microorganisms assimilate the substrate mainly at the point of contact where they grow. The model emphasizes effects of subst...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260350602
更新日期:1990-03-15 00:00:00
abstract::Compared to the conventional microbial and mammalian systems, transgenic plants produce proteins in a different matrix. This provides opportunities and challenges for downstream processing. In the context of the plant host Brassica napus (canola), this work addresses the bioprocessing challenges of solid fractionation...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10524
更新日期:2003-03-30 00:00:00
abstract::A comparative study of the performance of solid and liquid non-aqueous phases (NAPs) to enhance the mass transfer and biodegradation of hexane by Pseudomonas aeruginosa in two-phase partitioning bioreactors (TPPBs) was undertaken. A preliminary NAP screening was thus carried out among the most common solid and liquid ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22748
更新日期:2010-08-01 00:00:00