Abstract：
OBJECTIVE:A bio-based process is appealing for purification of L-lactic acid, the major enantiomer of polylactic acid syrup, generated by thermochemical processes at the end of life of PLA-based plastics, from its chiral impurity, D-lactic acid, before reuse. RESULTS:Polylactic acid (PLA), a renewable alternative to petroleum-derived plastics, contains a mixture of L- and D-lactic acid (LA) isomers with the L-isomer dominating (up to 95 %). A novel bio-based process was developed to produce chirally pure L-LA from syrup produced during recycling of PLA-plastics. This process utilizes an engineered Escherichia coli (strain DC1001) containing novel gene deletions (lld, ykg) that eliminated the oxidative metabolism of L-lactate, leaving the membrane-bound D-lactate dehydrogenases to selectively metabolize the D-isomer. Strain DC1001 removed 8.7 g D-lactate l(-1) from a PLA-syrup containing 135 g total lactic acid l(-1) in 24 h. Average rates of removal of D-lactic acid were 0.25 g D-lactate h(-1) (g cell dry weight)(-1) and 0.36 g D-lactate l(-1) h(-1). CONCLUSION:Bio-based purification of PLA-syrup utilizing E. coli strain DC1001 is an attractive process step during recycling of PLA-plastics. This selective oxidation process can also be used to remove chiral contamination of L-lactate in medical applications.
journal_name
Biotechnol Lettjournal_title
Biotechnology lettersauthors
Chauliac D,Pullammanappallil PC,Ingram LO,Shanmugam KTdoi
10.1007/s10529-015-1924-zsubject
Has Abstractpub_date
2015-12-01 00:00:00pages
2411-8issue
12eissn
0141-5492issn
1573-6776pii
10.1007/s10529-015-1924-zjournal_volume
37pub_type
杂志文章abstract：:Treatment of a hyperthermophilic enzyme, alkaline phosphatase from Pyrococcus furiosus (PfuAP), with EDTA completely deactivated PfuAP, indicating that the presence of one or more divalent metal ions is essential for its catalytic activity. Subsequent addition of various divalent metal ions to the apoprotein recovered...
journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-012-0998-0
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-007-9463-x
更新日期：2007-11-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-007-9353-2
更新日期：2007-07-01 00:00:00
abstract：OBJECTIVE:To develop recombinant factor IX (FIX) variants with augmented clotting activity. RESULTS:We generated three new variants, FIX-YKALW, FIX-ALL and FIX-LLW, expressed in SK-Hep-1 cells and characterized in vitro and in vivo. FIX-YKALW showed the highest antigen expression level among the variants (2.17 µg-mL),...
journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-020-03040-7
更新日期：2021-01-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-006-9140-5
更新日期：2006-10-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-012-0943-2
更新日期：2012-09-01 00:00:00
abstract：:Fluctuating light intensity had a more significant impact on growth of gametophytes of transgenic Laminaria japonica in a 2500 ml bubble-column bioreactor than constant light intensity. A fluctuating light intensity between 10 and 110 microE m(-2) s(-1), with a photoperiod of 14 h:10 h light:dark, was the best regime ...
journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-005-0938-3
更新日期：2005-09-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-006-9007-9
更新日期：2006-06-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章,评审
doi：10.1007/s10529-018-2555-y
更新日期：2018-06-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-014-1648-5
更新日期：2015-01-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-007-9409-3
更新日期：2007-09-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-011-0797-z
更新日期：2012-03-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-016-2058-7
更新日期：2016-06-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-020-02918-w
更新日期：2020-10-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-010-0428-0
更新日期：2011-02-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-015-1802-8
更新日期：2015-07-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1023/a:1025003800414
更新日期：2003-08-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章,评审
doi：10.1007/s10529-018-2516-5
更新日期：2018-04-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-005-2882-7
更新日期：2005-04-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-013-1140-7
更新日期：2013-05-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-008-9904-1
更新日期：2009-04-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-016-2112-5
更新日期：2016-08-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-015-1957-3
更新日期：2016-01-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-008-9821-3
更新日期：2008-12-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-008-9855-6
更新日期：2009-02-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
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更新日期：2005-05-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
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更新日期：2004-11-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-010-0336-3
更新日期：2010-11-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-012-0967-7
更新日期：2012-10-01 00:00:00
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journal_title：Biotechnology letters
pub_type： 杂志文章
doi：10.1007/s10529-004-3185-0
更新日期：2004-11-01 00:00:00
