Abstract:
:The phenomenon of the cell density effect is not readily explained by an obvious nutrient limitation, and a recent study has suggested that for recombinant Autographa californica multiple nucleopolyhedrovirus (rAcMNPV)-infected Sf9 cells, a drop in messenger RNA (mRNA) levels may be sufficient to explain the cell density effect for this system. The current study aims to investigate the response in cell-specific yields (viral DNA (vDNA), LacZ mRNA and β-galactosidase (β-Gal) protein) with increasing infection cell density (ICD) for rAcMNPV-infected Hi5 cells, where the rAcMNPV expresses the β-Gal gene under control of the polyhedral promoter. Hi5 cells in suspension culture of Express Five® medium were synchronously infected with a rAcMNPV at multiple ICDs between 0.5 and 6 × 10(6) cells/mL and a multiplicity of infection of 10 plaque-forming units (PFU)/cell either in the original or fresh medium conditions. There were negative correlations between the three key virus infection indicators (vDNA, mRNA and β-Gal) and the peak cell density (PCD). However, unlike infected Sf9 cells, the yield decline started at the lowest PCD investigated (0.6 × 10(6) cells/mL). Generally, the yield decline with increasing PCD was most pronounced for β-Gal followed by mRNA and was more moderate for vDNA. The decline was significantly reduced but not totally arrested when fresh medium replacement was used. The results suggest that the reduction in recombinant protein-specific yields at high PCDs is associated with limitations during the up-stream processes of replication and transcription rather than entirely caused by limitations during translation. In addition, low production rates at late infection stages of moderate to high ICDs are a probable cause of the cell density effect.
journal_name
Appl Microbiol Biotechnoljournal_title
Applied microbiology and biotechnologyauthors
Huynh HT,Tran TT,Chan LC,Nielsen LK,Reid Sdoi
10.1007/s00253-014-6260-zsubject
Has Abstractpub_date
2015-02-01 00:00:00pages
1687-700issue
4eissn
0175-7598issn
1432-0614journal_volume
99pub_type
杂志文章abstract::Peroxidases (PRX, EC 1.11.1.7) are widely distributed across microorganisms, plants, and animals; and, in plants, they have been implicated in a variety of secondary metabolic reactions. In particular, horseradish (Armoracia rusticana) root represents the main source of commercial PRX production. The prxC1a gene, whic...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-003-1273-z
更新日期:2003-10-01 00:00:00
abstract::Bioconversion of cassava-derived glucose to 2-keto-D-gluconic acid (2-KDG) using resting cells of immobilized Pseudomonas aeruginosa IFO 3448 was investigated. The tuberous roots of cassava were selected as the feedstock as they are inexpensive and widely available, and possess high amounts of starch (approximately 70...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-008-1374-9
更新日期:2008-04-01 00:00:00
abstract::The TonB system functions in iron transport and has been identified in certain Gram-negative bacteria. Recently, we reported three TonB systems in the Aeromonas hydrophila Chinese epidemic strain NJ-35, but the functions of these systems have not been thoroughly elucidated to date. In this study, we investigated the r...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-019-09757-4
更新日期:2019-05-01 00:00:00
abstract::By damaging DNA molecules, genotoxicants cause genetic mutations and also increase human susceptibility to cancers and genetic diseases. Over the past four decades, several assays have been developed in the budding yeast Saccharomyces cerevisiae to screen potential genotoxic substances and provide alternatives to anim...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章,评审
doi:10.1007/s00253-018-8783-1
更新日期:2018-03-01 00:00:00
abstract::Lipoxygenase (LOX; EC 1.13.11.12) is an enzyme which is widely used in food industry to improve aroma and rheological or baking properties of foods. A series of studies have proven that the flexible regions negatively relates to the thermal stability of enzymes. In this study, two highly flexible regions, residues(20-...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-013-5039-y
更新日期:2014-02-01 00:00:00
abstract::We used experimental evolution in order to identify genes involved in the adaptation of Saccharomyces cerevisiae to the early stages of alcoholic fermentation. Evolution experiments were run for about 200 generations, in continuous culture conditions emulating the initial stages of wine fermentation. We performed whol...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-014-6126-4
更新日期:2015-02-01 00:00:00
abstract::Sphingobium sp. strain TCM1 can significantly degrade chlorinated organophosphorus flame retardants, such as tris(2-chloroethyl) phosphate. The PhoK of strain TCM1 (Sb-PhoK) is the main alkaline phosphatase (APase) that catalyzes the last step in the degradation pathway. Here, we purified and characterized Sb-PhoK pro...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-019-10291-6
更新日期:2020-02-01 00:00:00
abstract::Reduction and biodegradation mechanisms of naphthylaminesulfonic azo dye amaranth using a newly isolated Shewanella decolorationis strain S12 were investigated. Under anaerobic conditions, amaranth was reduced by strain S12, and a stoichiometric amount of two reduction products RP-1 and RP-2 were generated. UV/visible...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-007-0838-7
更新日期:2007-06-01 00:00:00
abstract::To meet the demand for sustainable energy, aquifer thermal energy storage (ATES) is widely used in the subsurface in urban areas. However, contamination of groundwater, especially with chlorinated volatile organic compounds (CVOCs), is often being encountered. This is commonly seen as an impediment to ATES implementat...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-015-7241-6
更新日期:2016-04-01 00:00:00
abstract::Repetitious gene cassettes that encode the consensus decapeptide repeat of Mytilus edulis bioadhesive protein were designed, constructed, and expressed in Escherichia coli. The bioadhesive precursor (BP) with a relative molecular mass of 25,000 was expressed from one 600-bp gene at levels approaching 60% of total cell...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/BF00228610
更新日期:1993-05-01 00:00:00
abstract::Caffeic acid derivatives (CADs) are a group of bioactive compounds which are produced in Echinacea species especially Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida. Echinacea is a popular herbal medicine used in the treatment of common cold and it is also a prominent dietary supplement used through...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章,评审
doi:10.1007/s00253-014-5962-6
更新日期:2014-09-01 00:00:00
abstract::Programmable transcriptional regulation is a powerful tool to study gene functions. Current methods to selectively regulate target genes are mainly based on promoter exchange or on overexpressing transcriptional activators. To expand the discovery toolbox, we designed a dCas9-based RNA-guided synthetic transcription a...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-020-10900-9
更新日期:2020-11-01 00:00:00
abstract::Acyl-CoAs are crucial compounds involved in essential metabolic pathways such as the Krebs cycle and lipid, carbohydrate, and amino acid metabolisms, and they are also key signal molecules involved in the transcriptional regulation of lipid biosynthesis in many organisms. In this study, we took advantage of the high s...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-016-7635-0
更新日期:2016-08-01 00:00:00
abstract::A fundamental issue in biotechnology is how to breed useful strains of microorganisms for efficient production of valuable biomaterials. On-going and more recent developments in gene manipulation technologies and chromosomal and genomic modifications in particular have facilitated important contributions in this area....
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章,评审
doi:10.1007/s00253-009-2144-z
更新日期:2009-10-01 00:00:00
abstract::Microsomal fraction of fungal cells grabs the attention of many researchers for it contains enzymes that play a role in biotechnologically relevant processes. Microsomal enzymes, namely, CYP450s, were shown to metabolize a wide range of xenobiotic compounds, including PAHs, PCBs, dioxins, and endocrine disruptors, and...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章,评审
doi:10.1007/s00253-013-5347-2
更新日期:2013-12-01 00:00:00
abstract::Previous work showed that random mutagenesis produced a mutant of toluene ortho-monooxygenase (TOM) of Burkholderia cepacia G4 containing the V106A substitution in the hydroxylase alpha-subunit (TomA3) that changed the color of the cell suspension from wild-type brown to green in rich medium. Here, DNA shuffling was u...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-004-1698-z
更新日期:2005-01-01 00:00:00
abstract::Resolution of (R,S)-ibuprofen enantiomers by esterification in different organic solvents was studied using Candida cylindracea lipase. This enzyme preparation had high enantiospecificity for S(+)-ibuprofen in the esterification reaction of a racemic ibuprofen with primary alcohols. The esterification yields of second...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/BF00169420
更新日期:1992-10-01 00:00:00
abstract::The process of nitrification has the potential for the in situ bioremediation of halogenated compounds provided a number of challenges can be overcome. In nitrification, the microbial process where ammonia is oxidized to nitrate, ammonia-oxidizing bacteria (AOB) are key players and are capable of carrying out the biod...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章,评审
doi:10.1007/s00253-010-2454-1
更新日期:2010-03-01 00:00:00
abstract::A recombinant oleate hydratase from Lysinibacillus fusiformis converted ricinoleic acid to a product, whose chemical structure was identified as the novel compound 10,12-dihydroxystearic acid by gas chromatograph/mass spectrometry, Fourier transform infrared, and nuclear magnetic resonance analysis. The reaction condi...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-013-4728-x
更新日期:2013-10-01 00:00:00
abstract::This review presents developments and applications in bioleaching and mineral biooxidation since publication of a previous mini review in 2003 (Olson et al. Appl Microbiol Biotechnol 63:249-257, 2003). There have been discoveries of newly identified acidophilic microorganisms that have unique characteristics for effec...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章,评审
doi:10.1007/s00253-013-5095-3
更新日期:2013-09-01 00:00:00
abstract::A chromosomal DNA fragment of 7.8 kb from Lactobacillus coryniformis CECT 5711 was cloned in Escherichia coli K-12 and was found to express a functional beta-galactosidase. Nucleotide sequence analysis showed that this fragment contained two partially overlapping genes, the lacL (1,881 bp) and the lacM (960 bp), that ...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-006-0510-7
更新日期:2006-12-01 00:00:00
abstract::While diatoms are widely present in terms of diversity and abundance in nature, few species are currently used for biotechnologically applications. Most studies have focussed on intracellularly synthesised eicosapentaenoic acid (EPA), a polyunsaturated fatty acid (PUFA) used for pharmaceutical applications. Applicatio...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章,评审
doi:10.1007/s00253-002-1177-3
更新日期:2003-02-01 00:00:00
abstract::Production of bacterial cellulose (BC) using sugar cane molasses (MO) with/without the presence of lignosulfonate (MOL) as a sole carbon source in a Hestrin-Schramm medium (HS) was investigated. Six strains of Acetobacter xylinum [American Type Culture Collection 10245 and Institute of Fermentation in Osaka (IFO) 1369...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-005-0265-6
更新日期:2006-09-01 00:00:00
abstract::Pseudomonas resinovorans, a known medium-chain-length (mcl-) poly(hydroxyalkanoate) (PHA) producer, was grown on 13-methyltetradecanoic acid (13-MTDA) and a mixture of isostearic acid (IA) isomers to produce methyl-branched mcl-PHA polymers. Shake-flask experiments revealed polymer productivities (the percent of the c...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-009-2134-1
更新日期:2009-11-01 00:00:00
abstract::In order to achieve efficient homo L-lactic acid fermentation from xylose, we first carried out addition of xylose assimilation ability to Lactococcus lactis IL 1403 by introducing a plasmid carrying the xylRAB genes from L. lactis IO-1 (pXylRAB). Then modification of xylose assimilation pathway was carried out. L. la...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-011-3342-z
更新日期:2011-09-01 00:00:00
abstract::The xylose-fermenting yeast Spathaspora passalidarum showed excellent fermentation performance utilizing glucose and xylose under anaerobic conditions. But this yeast is highly sensitive to the inhibitors such as furfural present in the pretreated lignocellulosic biomass. In order to improve the inhibitor tolerance of...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-011-3693-5
更新日期:2012-03-01 00:00:00
abstract::Protein translation, translocation, folding, processing, and secretion in eukaryotic cells are complex and not always straightforward processes, e.g., different routes of secretion and degradation exist. Formation of malfolded proteins in the endoplasmic reticulum (ER) can be one of the major bottlenecks for recombina...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-012-3933-3
更新日期:2012-03-01 00:00:00
abstract::Streptomyces coelicolor A3(2) is a rubber-degrading actinomycete that harbors one gene coding for a latex clearing protein (lcpA3(2)). Within the genome of S. coelicolor A3(2), we identified a gene coding for a novel protein of the TetR family (LcpRBA3(2)) downstream of lcpA3(2) and demonstrated its binding upstream o...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-019-09896-8
更新日期:2019-07-01 00:00:00
abstract::Lactobacillus plantarum MA2 was isolated from traditional Chinese Tibet kefir grains, which possess several excellent properties and functions. We previously demonstrated the antioxidant activities of this bacterium in vitro. However, the maintenance and survival of L. plantarum MA2 inside the murine intestinal tract,...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-016-7581-x
更新日期:2016-08-01 00:00:00
abstract::Chitooligosaccharides have important application value in the fields of food and agriculture. Chitosanase can degrade chitosan to obtain chitooligosaccharides. The marine metagenome contains many genes related to the degradation of chitosan. However, it is difficult to mine valuable genes from large gene resources. Th...
journal_title:Applied microbiology and biotechnology
pub_type: 杂志文章
doi:10.1007/s00253-020-10715-8
更新日期:2020-08-01 00:00:00