Abstract：
:By using very active and very stable trypsin agarose derivatives, we have optimized the design of the synthesis of a model dipeptide, benzoylarginine leucinamide, by two different strategies: (i) kinetically controlled synthesis (KCS), by using benzoyl arginine ethyl ester and leucinamide as substrates, and (ii) thermodynamically controlled synthesis (TCS), by using benzoyl arginine and leucinamide as substrates. In each strategy, we have studied the integrated effect of a number of variables that define the reaction medium on different parameters of industrial interest, e.g. time course of peptide synthesis, higher synthetic yields, and stability of the catalyst, as well as aminolysis/hydrolysis ratios and rate of peptide hydrolysis in the case of KCS. Both synthetic approaches were carried out in monophasic water or water-organic cosolvent systems. We have mainly tested a number of variables, e.g. temperature, polarity of the reaction medium (presence of cosolvents, presence of ammonium sulfate), and exact structure of the trypsin derivatives. Optimal experimental conditions for these synthetic approaches were established in order to simultaneously obtain good values for all industrial parameters. The use of previously stabilized trypsin derivatives greatly improves the design of these synthetic approaches (e.g. by using drastic experimental conditions: 1 M ammonium sulfate (KCS) or 90% organic cosolvents (TCS]. In these conditions, our derivatives preserve more than 95% of activity after 2 months and we have been able to reach synthetic productivities of 180 (KCS) and 1 (TCS) tons of dipeptide per year per liter of catalyst.
journal_name
Enzyme Microb Technoljournal_title
Enzyme and microbial technologyauthors
Blanco RM,Alvaro G,Guisán JMdoi
10.1016/0141-0229(91)90093-pkeywords:
subject
Has Abstractpub_date
1991-07-01 00:00:00pages
573-83issue
7eissn
0141-0229issn
1879-0909pii
0141-0229(91)90093-Pjournal_volume
13pub_type
杂志文章abstract：:Progesterone 5β-reductases (P5βRs) are involved in 5β-cardenolide formation by stereo-specific reduction of the △4,5 double bond of steroid precursors. In this study a steroid 5β-reductase was identified in Capsella rubella (CrSt5βR1) and its function in steroid 5β-reduction was validated experimentally. CrSt5βR1 is c...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
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更新日期：2020-03-01 00:00:00
abstract：:The stabilization of fungal cellulases by spray drying, the thermal stability of Penicillium occitanis cellulases and the effect of some additives were studied. We observed that CMCase activity presents a good stability at 50 degrees C, even after 60 h of incubation. On the other hand, beta-glucosidase activity was mo...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/s0141-0229(00)00322-7
更新日期：2001-02-01 00:00:00
abstract：:Data and a semi-empirical model are presented that describe the affinity interaction of yeast cells with a Concanavalin A derivatised surface. The model uses 3 parameters to describe the time course of cell attachment from a flowing suspension of yeast cells, over a range of flow rates, and gives an effective global f...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/s0141-0229(99)00161-1
更新日期：2000-02-01 00:00:00
abstract：:Phytate is the major storage form of phosphorus in plants. It is present in cereals and raw materials of vegetable origin used in animal and human diets. However, non-ruminant animals have little phytase activity in their guts and, therefore, cannot digest phytate. As a result, almost all dietary phytate is discharged...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2020.109533
更新日期：2020-06-01 00:00:00
abstract：:In this work, porous biochar derived from sugarcane bagasse was prepared and then coated with different amounts of chitosan (C@CS) for cellulase immobilization. Cellulase was covalently immobilized on the support by using glutaraldehyde as a linker. The chemical characteristics and morphology of the samples were deter...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2020.109561
更新日期：2020-08-01 00:00:00
abstract：:We previously constructed three recombinant phyA mutant strains (PP-NPm-8, PP-NPep-6A and I44E/T252R-PhyA), showing improved catalytic efficiency or thermostability of Aspergillus niger N25 phytase, by error-prone PCR or site-directed mutagenesis. In this study, directed evolution and site-directed mutagenesis were fu...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2017.09.010
更新日期：2018-01-01 00:00:00
abstract：:An approach was developed to enhance the efficiency for the bioconversion of 1-(3-hydroxyphenyl)-2-(methyamino)-ethanone to (R)-phenylephrine. The strain Serratia marcescens N10612, giving the benefit of 99% enantiomeric excess in (R)-PE conversion, was used. The fermentation was devised to harvest cells with high hyd...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2015.11.004
更新日期：2016-05-01 00:00:00
abstract：:Acetobacter pasteurianus oxidizes glycidol with high activity, comparable to the oxidation of ethanol. The organism has a preference for the S-enantiomer, and the kinetic resolution process obeys a simple relationship, indicating an enantiomeric ratio (E) of 19. The compound is converted into glycidic acid, although a...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(94)90143-0
更新日期：1994-12-01 00:00:00
abstract：:Musky macrolactones are an important group of compounds used in high-valued perfumery. An enzymatic cascade reaction including cytochrome P450 hydroxylase and lipase was explored to biosynthesize musky macrolactones. Firstly, fatty acids were hydroxylated by P450 hydroxylase to produce the corresponding ω-hydroxy fatt...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2019.109417
更新日期：2019-12-01 00:00:00
abstract：:Ergosterol, like cholesterol, has many beneficial physiological activities, and because it has no adverse clinical problem with cholesterol, it is a substance that can be used as a biomaterial in the food and cosmetics industry. However, ergosterol has low oil solubility and is easily crystallized, which is problemati...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2020.109581
更新日期：2020-09-01 00:00:00
abstract：:Thiol dioxygenases are non-heme mononuclear-iron proteins and belong to the cupin superfamily. In 2014, mercaptosuccinate dioxygenase (Msdo) of Variovorax paradoxus B4 was identified as another bacterial cysteine dioxygenase (Cdo) homolog catalyzing the conversion of mercaptosuccinate (MS) into succinate and sulfite. ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2018.09.007
更新日期：2019-01-01 00:00:00
abstract：:The novel termite gut metagenomic-derived GH11 xylanase gene xyl7 was expressed in Escherichia coli BL21, and the purified XYL7 enzyme exhibited high specific activity (6340U/mg) and broad pH active range of 5.5-10.0. Directed evolution was employed to enhance the thermostability of XYL7; two mutants (XYL7-TC and XYL7...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2014.11.005
更新日期：2015-03-01 00:00:00
abstract：:The characterization of the S' subsite specificity of native and ethylated alpha-chymotrypsin has been studied via acyl transfer reaction in acetonitrile containing 10 vol% of water. Using Ac-Tyr-OEt as acyl donor, we investigated the partitioning of acyl-chymotrypsins between water and amino acid and peptide-derived ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(94)90125-2
更新日期：1994-07-01 00:00:00
abstract：:Kumamolisin from Alicyclobacillus sendaiensis strain NTAP-1 is a serine protease with collagenase activity. After molecular engineering, a kumamolisin mutant, named Kuma030, was obtained with high proteolytic activity against gluten, which might cause celiac disease. Kuma030 exhibited its potential application in indu...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2019.05.013
更新日期：2019-10-01 00:00:00
abstract：:A method to stably immobilize microbes on electrodes was developed. Resting cells of Methylobacterium extorquens AM1(MeAM1) were caged within multiwalled carbon nanotubes (MWNTs)by adding the cells to a water dispersion of MWNTs then allowing the resulting mixture to dry on electrodes. The MeAM1-MWCNTs electrode thus ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2018.06.004
更新日期：2018-10-01 00:00:00
abstract：:Controlled hydrolysis of lactonic sophorolipids from Starmerella bombicola yields a previously undescribed sophorose analog that potently induces cellulase in Trichoderma reesei Rut-C30. Acid treatment of natural sophorolipids results in a mixture of monoacetylated, deacetylated, and diacetylated sophorolipids in acid...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2016.01.003
更新日期：2016-04-01 00:00:00
abstract：:In the paper, a green and efficient biosynthetical technique was reported for preparing cadmium sulfide (CdS) quantum dots, in which Escherichia coli (E. coli) was chosen as a biomatrix. Fluorescence emission spectra and fluorescent microscopic photographs revealed that as-produced CdS quantum dots had an optimum fluo...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2016.09.017
更新日期：2017-01-01 00:00:00
abstract：:Horseradish peroxidase (HRP) was successfully purified from horseradish roots by a two-stage reverse-micellar extraction from the dialyzed aqueous extract. The anionic surfactant AOT dissolved in isooctane was used to produce the reverse-micellar phases. The narrow pH range at which HRP solubilization occurred was exp...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(95)00031-3
更新日期：1996-04-01 00:00:00
abstract：:Marine microbes have gained significant attention as potential biofactories for broad spectrum bioactive compounds. In the recent years, bioactive biosurfactants have warranted renewed interest from both environmental and clinical sectors as anti-biofilm agents due to their excellent properties of dispersing microbial...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2018.09.008
更新日期：2019-01-01 00:00:00
abstract：:A novel magnetic Fe3O4 nanoparticles (MNPs) coupled with agarose (AMNPs) was synthesized using co-precipitation via alkaline condition and span-80 surfactants in organic solvent. Iminodiacetate was first attached to the MNPs through epichlorohydrin agent and then chelated with metal ions. The morphology and chemical p...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2014.05.008
更新日期：2014-09-01 00:00:00
abstract：:The present work describes a novel central pathway engineering method that has been designed with the aim to increase the carbon conversion rates under oxidizing conditions in L. lactis fermentations. The nisin producer L. lactis ATCC11454 strain has been genetically engineered by cloning a truncated version of the ph...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2012.04.007
更新日期：2012-08-10 00:00:00
abstract：:Phenylalanine ammonia-lyase (PAL) gene plays an important role in the synthesis of flavones, lignin, and other bioactive compounds in living organisms. Inonotus baumii, the only known flavone-producing filamentous fungus, is of great importance in the investigation of flavone metabolic pathways. To study the function ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2017.10.010
更新日期：2018-05-01 00:00:00
abstract：:The selected thermotolerant, lactose-utilizing yeast strain Kluyveromyces marxianus NBIMCC 8362 possesses high specific d-amino acid oxidase activity (60Ug(-1)), which was increased nine-fold (545Ug(-1)) by design of the growth medium and conditions for d-amino oxidase induction. Applying an optimized simple and rapid...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2007.08.010
更新日期：2008-01-01 00:00:00
abstract：:The mass distribution regularity in substrate of solid-state fermentation (SSF) has rarely been reported due to the heterogeneity of solid medium and the lack of suitable instrument and method, which limited the comprehensive analysis and enhancement of the SSF performance. In this work, the distributions of water, bi...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2014.02.007
更新日期：2014-05-10 00:00:00
abstract：:Glucose is the typical carbon source for producing microbial polyunsaturated fatty acids (PUFA) with single cell microorganisms such as thraustochytrids. We assessed the use of a fish oil derived glycerol by-product (raw glycerol), produced by a fish oil processing plant, as a carbon source to produce single cell oil ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2010.11.008
更新日期：2011-03-07 00:00:00
abstract：:The lipases from Thermomyces lanuginosus and Pseudomonas cepacia have been immobilized on octyl and cyanogen bromide (CNBr) agarose beads. The immobilization on octyl-agarose is slowed with increasing ionic strength, while the immobilization on CNBr is not significantly affected by the ionic strength. The inhibition o...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2015.02.001
更新日期：2015-04-01 00:00:00
abstract：:Addition of non-ionic surfactants (NIS) is known to accelerate enzymatic lignocellulose hydrolysis. The mechanism behind this accelerating effect is still not elucidated but has been hypothesized to originate from favorable NIS-lignin interactions which alleviate non-productive adsorption of cellulases to lignin. In t...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2011.06.015
更新日期：2011-09-10 00:00:00
abstract：:beta-amylases are used in production of maltose syrup. It is shown that sweet potato beta-amylase can be purified by affinity precipitation with alginate with 80% activity yield and 44 fold purification. SDS-PAGE of the purified protein showed a single band and a subunit weight of 50 kDa. Preliminary data with soybean...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/s0141-0229(01)00338-6
更新日期：2001-06-07 00:00:00
abstract：:Biosensors have been extensively studied during the last 20 years, and a myriad of laboratory biosensors have been developed. Improvements are required in biosensor design and performance before they become widely accepted in industrial process monitoring. However, as the biotechnology industry expands, biosensors may...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章,评审
doi：10.1016/0141-0229(91)90115-q
更新日期：1991-12-01 00:00:00
abstract：:Amylosucrase (ASase) has great industrial potential owing to its multifunctional activities, including transglucosylation, polymerization, and isomerization. In the present study, the properties of Deinococcus geothermalis ASase (DGAS) expressed in Corynebacterium glutamicum (cDGAS) and purified via Ni-NTA affinity ch...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2019.109505
更新日期：2020-04-01 00:00:00
