Abstract:
:Alkyl glycosides are attractive surfactants because of their high surface activity and good biodegradability and can be produced from renewable resources. Through enzymatic catalysis, one can obtain well-defined alkyl glycosides, something that is very difficult to do using conventional chemistry. However, there is a need for better enzymes to get a commercially feasible process. A thermostable β-glucosidase from the well-studied glycoside hydrolase family 1 from Thermotoga neapolitana, TnBgl1A, was mutated in an attempt to improve its value for synthesis of alkyl glycosides. This was done by rational design using prior knowledge from structural homologues together with a recently generated model of the enzyme in question. Three out of four studied mutations increased the hydrolytic reaction rate in an aqueous environment, while none displayed this property in the presence of an alcohol acceptor. This shows that even if the enzyme resides in a separate aqueous phase, the presence of an organic solvent has a great influence. We could also show that a single amino acid replacement in a less studied part of the aglycone subsite, N220F, improves the specificity for transglycosylation 7-fold and thereby increases the potential yield of alkyl glycoside from 17% to 58%.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Lundemo P,Adlercreutz P,Karlsson ENdoi
10.1128/AEM.00359-13subject
Has Abstractpub_date
2013-06-01 00:00:00pages
3400-5issue
11eissn
0099-2240issn
1098-5336pii
AEM.00359-13journal_volume
79pub_type
杂志文章abstract::Chlorpromazine was used to perform a test for the detection of microbial peroxidase activities. The compound acts as both a cell permeabilizer and a reagent in the procedure developed which allows the detection of peroxidase and peroxidase like reactions both semiquantitatively in whole cell determinations and quantit...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.52.6.1433-1435.1986
更新日期:1986-12-01 00:00:00
abstract::Escherichia coli, commonly used in chemotaxis studies, is attracted mostly by amino acids, sugars, and peptides. We envisioned modifying the chemotaxis specificity of E. coli by expressing heterologous chemoreceptors from Pseudomonas putida enabling attraction either to toluene or benzoate. The mcpT gene encoding the ...
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doi:10.1128/AEM.01362-18
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00346-13
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.59.8.2449-2456.1993
更新日期:1993-08-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.71.11.7548-7550.2005
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.34.1.30-33.1977
更新日期:1977-07-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.56.12.3649-3656.1990
更新日期:1990-12-01 00:00:00
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pub_type: 杂志文章
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pub_type: 杂志文章
doi:10.1128/AEM.71.1.131-139.2005
更新日期:2005-01-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02572-16
更新日期:2016-11-21 00:00:00
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pub_type: 杂志文章
doi:10.1128/AEM.02425-12
更新日期:2013-02-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.59.6.1767-1773.1993
更新日期:1993-06-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.33.5.1207-1208.1977
更新日期:1977-05-01 00:00:00
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pub_type: 杂志文章
doi:10.1128/AEM.70.7.4363-4366.2004
更新日期:2004-07-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00323-16
更新日期:2016-06-13 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.12.4493-4498.1996
更新日期:1996-12-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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更新日期:2007-02-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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更新日期:2020-06-17 00:00:00
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journal_title:Applied and environmental microbiology
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更新日期:2016-08-15 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00625-07
更新日期:2007-08-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.58.10.3380-3386.1992
更新日期:1992-10-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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更新日期:2018-01-02 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.35.5.978-979.1978
更新日期:1978-05-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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更新日期:2012-08-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.71.2.621-628.2005
更新日期:2005-02-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.53.10.2487-2495.1987
更新日期:1987-10-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02217-09
更新日期:2010-01-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.49.6.1530-1531.1985
更新日期:1985-06-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00067-13
更新日期:2013-05-01 00:00:00