Abstract:
:The hybridization of the native and chemically inactivated aspartase from Escherichia coli was studied. Preparations of the tetrameric enzyme obtained by mixing the native and N-ethylmaleimide (NEM)-inactivated aspartase in 4 M guanidine-HCl followed by 51-fold dilution at room temperature retained catalytic activity. Affinity chromatography on AF-Red TOYO-PEARL separated several active components in the hybridized preparations, and the presence of [14C]NEM-inactivated subunits in the active hybrids was demonstrated. The addition of the native aspartase to Sepharose-bound NEM-inactivated enzyme in 4 M guanidine-HCl resulted in the formation of an immobilized enzyme with enzyme activity. The specific activity of the various hybrids, composed of unmodified and [14C]NEM-inactivated subunits, was roughly proportional to the number of unmodified subunits in each tetramer. Furthermore, when reversible denaturation was conducted on mixtures of the native and NEM-inactivated enzyme at various proportions, the enzyme activity recovered was proportional to the amount of the native enzyme added. These results strongly suggest that each subunit makes an independent contribution to the overall enzyme activity regardless of the presence of other subunits in the same molecule. The theoretical and practical implications of this work are discussed.
journal_name
Biotechnol Appl Biochemjournal_title
Biotechnology and applied biochemistryauthors
Imaishi H,Yumoto N,Tokushige Msubject
Has Abstractpub_date
1990-04-01 00:00:00pages
196-205issue
2eissn
0885-4513issn
1470-8744journal_volume
12pub_type
杂志文章abstract::A simple and cost-effective method is described to sequence double-stranded DNA (< 100 ng) using a very small amount of fluorescent sequencing mix (one-tenth of manufacturer-recommended amount). The modification has significant advantages over conventional protocols and can be used to sequence, using a single sequenci...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1997-08-01 00:00:00
abstract::Chronic myelogenous leukemia (CML) is a hematologic malignancy characterized by excessive growth of myeloid cells and their progenitors. The proportion of spectrin dimers compared to tetramers extracted from membranes at 4 degrees C, under low ionic strength conditions, increased in CML erythrocytes. These also displa...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章,评审
doi:
更新日期:1990-10-01 00:00:00
abstract::c-Jun is a highly oncogenic transcription factor involved in the development of different types of cancer. In the present study we have generated c-Jun-binding-affinity proteins from a phage-displayed library of so-called 'Affibody ligands', developed by combinatorial engineering of a non-immunoglobulin-based scaffold...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1042/BA20070178
更新日期:2009-01-01 00:00:00
abstract::The structural underpinnings of O₂ activation in P450s have been limited by the inability to trap unstable oxy complexes in the crystalline state for structure determination. To date there are only two known oxy P450 structures. Even so, much is known about O₂ activation in P450cam and the role that redox partner bind...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章,评审
doi:10.1002/bab.1056
更新日期:2013-01-01 00:00:00
abstract::The development of subunit vaccines is presently the main strategy being evaluated for prevention of infectious diseases. The use of recombinant-DNA techniques has facilitated the development of new principles for design and production of subunit vaccines. First of all, the properties of a target protein immunogen can...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章,评审
doi:10.1042/ba20000034
更新日期:2000-10-01 00:00:00
abstract::The membranotropic properties of block co-polymers and their protein conjugates were studied by their effect on the rate of oxygen consumption by isolated liver mitochondria and on thymus-derived lymphocytes. The block co-polymers consisted of poly(ethylene oxide) (PoE) [poly(ethylene glycol)] and poly(propylene oxide...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1993-12-01 00:00:00
abstract::Human thymosin alpha1 is an effective immune system enhancer for the treatment of cancer and viral diseases. Therefore the development of new methods for its synthesis is an urgent problem. In the present work, we propose an efficient scalable scheme for the production of recombinant thymosin alpha1. We used an expres...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1042/BA20100027
更新日期:2010-05-19 00:00:00
abstract::Restoration of insulin secretion by transplantation of isolated islets is a treatment for type Ι diabetes mellitus. One of the major issues with clinical treatment of islet transplantation is how to maintain islet viability during transportation from the donor to the patient. We developed a method that uses alginate e...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.1295
更新日期:2015-07-01 00:00:00
abstract::In our work, one-step electro-deposition method was adopted to produce polyaniline (PANI) and functional multiwalled carbon nanotubes (f-MWCNTs) films on glass carbon electrodes, and the modified electrodes were applied as an electrochemical sensor for determination of 10-hydroxycamptothecine (10-HCPT). The f-MWCNTs w...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.2041
更新日期:2020-09-24 00:00:00
abstract::Sometimes it is necessary to obtain thrombin from limited amounts of human plasma for laboratory assay. None of the available purification methods easily deals with this subject. The procedure described in the present paper uses a readily available pharmaceutical agent, argatroban, to construct an affinity matrix. Arg...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1042/BA20050057
更新日期:2005-10-01 00:00:00
abstract::Catalytic properties of Escherichia coli polyphosphate kinase (EC 2.7.4.1), a promising enzyme for use in ATP regeneration (Hoffman, et al., 1988, Biotechnol. Appl. Biochem. 10, 107-117), are reported here. E. coli polyphosphate kinase (PPK) is broadly active in the pH range 5.5 to 8.5, having an optimal Vmax at pH 7....
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1992-04-01 00:00:00
abstract::Medulloblastoma is the most common malignant pediatric brain tumor in children. GPR137 is a ubiquitously expressed gene in the central nervous system. It has been reported that GPR137 modulates malignant proliferation of glioma cells. However, the relationship between GPR137 and medulloblastoma is still unknown. In th...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.1331
更新日期:2015-11-01 00:00:00
abstract::The urinary C-terminal telopeptide fragment of type II collagen (uCTX-II) has been reported as the efficient blood-based biomarker for osteoarthritis, which affects knees, hands, spine, and hips. This study reports a sensing strategy with antibody-conjugated gold nanoparticles (GNP) on an interdigitated electrode (IDE...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.1981
更新日期:2020-07-04 00:00:00
abstract::The effects of chitin [(1-->4)-2-acetamido-2-deoxy-beta-D-glucan] and its partially deacetylated derivatives, chitosans, on the human dermal fibroblast-mediated contraction of collagen lattices were examined in vitro as a model for the contraction of cutaneous wounds in vivo. Chitosan CL313A, a short-chain-length 89% ...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1042/ba20020040
更新日期:2002-12-01 00:00:00
abstract::The dynamic gassing-out method was used to assess the effect of stirrer speed, air flow rate and alginate concentration on the overall volumetric oxygen mass transfer coefficient (K(L)a) in a bench-top stirred fermenter equipped with two Rushton-type turbines. As the alginate concentration in the medium was increased ...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1042/BA20030213
更新日期:2004-10-01 00:00:00
abstract::A pathway for the synthesis of the repeating tetrasaccharide units in gellan gum from Pseudomonas elodea is proposed. The enzymes presumed to be involved in the synthesis of the activated precursors UDP-glucose, TDP-rhamnose, and UDP-glucuronic acid were detected and assayed in crude cell extracts of the gellan-produc...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1991-12-01 00:00:00
abstract::Mechano-growth factor (MGF), an alternative splicing variant of insulin-like growth factor-1 (IGF-1) gene, promotes cell proliferation and inhibits cell differentiation. It also plays an important role in tumor development. It is important to optimize the production process and achieve MGF protein because there is no ...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.1312
更新日期:2015-09-01 00:00:00
abstract::The aim of this paper is to make the point on the fortieth years study on the β-glycosidase from Sulfolobus solfataricus. This enzyme represents one of the thermophilic biocatalysts, which is more extensively studied as witnessed by the numerous literature reports available since 1980. Comprehensive biochemical studie...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章,评审
doi:10.1002/bab.1982
更新日期:2020-07-01 00:00:00
abstract::An inducible esterase has been isolated from a liquid culture of Aspergillus niger grown on sugar-beet pulp. The enzyme was active on methyl esters of cinnamic acids, caffeic > p-coumaric > ferulic, and is therefore termed a cinnamoyl esterase. The enzyme was not active on methyl sinapinate, a good substrate for ferul...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1996-06-01 00:00:00
abstract::alpha-Cyclodextrin (CD) was converted by Bacillus macerans cyclodextrin glucanotransferase into highly insoluble high-amylose starch with a low average degree of polymerization (56-73), in yields as high as 78% over a wide range of temperatures (25-70 degreesC). Ability to undergo this conversion was highly concentrat...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1998-12-01 00:00:00
abstract::Ganoderma neo-japonicum is a well-known medicinal mushroom in Asian countries. However, scientific validations on its curative activities are confined to cirrhosis and diabetes. In this study, the anticancer properties of G. neo-japonicum were evaluated using cellular and computational models. The ethanolic extract (E...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.2013
更新日期:2020-08-28 00:00:00
abstract::Glycoprotein D (gD2) is the most important candidate antigen for herpes simplex virus type 2 (HSV-2) vaccine development. Establishment of a stable eukaryotic cell line to overexpress gD2 and an efficient purification process to purify is essential for the development of subunit vaccine against HSV-2. The DNA sequence...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.1386
更新日期:2016-05-01 00:00:00
abstract::In the present study, the growth and key metabolic features of a gene-transfected Drosophila melanogaster (fruitfly) S2 (Schneider 2) cell population (S2AcRVGP cells), cultured in Sf900-II medium, have been evaluated to provide substantial support for the development of a bioprocess to produce RVGP (rabies-virus glyco...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1042/BA20060148
更新日期:2008-01-01 00:00:00
abstract::Two different enzymes that metabolize lactate in the presence of oxygen, either to acetate plus CO2 (lactate 2-mono-oxygenase; Lmox) or to pyruvate plus H2O2 (lactate oxidase; Lox) were encapsulated in human and murine red blood cells (RBCs). Lmox shows a low affinity for lactate (Km 22 mM) and thus works at a low rat...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1995-12-01 00:00:00
abstract::The therapeutic potential of microRNA-21 (miR-21) small-molecule inhibitors has been of particular interest to medicinal chemists. Moreover, the development of more facile screening methods is lacking. In the present study, two potential screening strategies for miR-21 small-molecule inhibitor including the stem-loop ...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.1756
更新日期:2019-09-01 00:00:00
abstract::In order to impart an ability for receptor-independent transmembrane transfer to water-soluble proteins, it has been suggested that they be hydrophobized by lipid groups (fatty acids, etc.). To this end, systems of reversed micelles of surfactants in organic solvents were used as reaction media for protein modificatio...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1990-02-01 00:00:00
abstract::Yeast cells immobilized by entrapment in an insolubilized gelatin gel have been investigated with regard to their pattern of growth and respiratory activity. Mass-transfer resistance offered by the matrix and growth of the entrapped cells determine a gradient of nutrients throughout the gel which is responsible for bo...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:
更新日期:1996-02-01 00:00:00
abstract::Higher thermostability or acid resistance for fungal α-amylase will help to improve the sugar-making process and cut down the production costs. Here, the thermostability or acid resistance of Rhizopus oryzae α-amylase (ROAmy) was significantly enhanced by site-directed evolution based on multiple sequence alignment (M...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.1907
更新日期:2020-07-01 00:00:00
abstract::Human erythrocytes from ten patients with chronic obstructive pulmonary disease (COPD) were loaded with increasing amounts of dexamethasone 21-phosphate and were re-infused into the original donors. Drug-loaded erythrocytes acted as circulating bioreactors, converting the non-diffusible dexamethasone 21-phosphate into...
journal_title:Biotechnology and applied biochemistry
pub_type: 临床试验,杂志文章
doi:10.1042/ba20000087
更新日期:2001-04-01 00:00:00
abstract::We have explored the adaptation of the cytochromes P450 (P450) of deep-sea bacteria to high hydrostatic pressures. Strict conservation of the protein fold and functional importance of protein-bound water make P450 a unique subject for the studies of high-pressure adaptation. Earlier, we expressed and purified a fatty-...
journal_title:Biotechnology and applied biochemistry
pub_type: 杂志文章
doi:10.1002/bab.1083
更新日期:2013-01-01 00:00:00