Engineering of an l-arabinose metabolic pathway in Corynebacterium glutamicum
Corynebacterium glutamicum was metabolically engineered to broaden its substrate utilization range to include the pentose sugar l -arabinose, a product of the degradation of lignocellulosic biomass. The resultant CRA1 recombinant strain expressed the Escherichia coli genes araA , araB , and araD enc...
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Published in | Applied microbiology and biotechnology Vol. 77; no. 5; pp. 1053 - 1062 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
Berlin/Heidelberg
Springer Berlin Heidelberg
2008
Springer Springer Nature B.V |
Subjects | |
Online Access | Get full text |
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Summary: | Corynebacterium glutamicum
was metabolically engineered to broaden its substrate utilization range to include the pentose sugar
l
-arabinose, a product of the degradation of lignocellulosic biomass. The resultant CRA1 recombinant strain expressed the
Escherichia coli
genes
araA
,
araB
, and
araD
encoding
l
-arabinose isomerase,
l
-ribulokinase, and
l
-ribulose-5-phosphate 4-epimerase, respectively, under the control of a constitutive promoter. Unlike the wild-type strain, CRA1 was able to grow on mineral salts medium containing
l
-arabinose as the sole carbon and energy source. The three cloned genes were expressed to the same levels whether cells were cultured in the presence of
d
-glucose or
l
-arabinose. Under oxygen deprivation and with
l
-arabinose as the sole carbon and energy source, strain CRA1 carbon flow was redirected to produce up to 40, 37, and 11%, respectively, of the theoretical yields of succinic, lactic, and acetic acids. Using a sugar mixture containing 5%
d
-glucose and 1%
l
-arabinose under oxygen deprivation, CRA1 cells metabolized
l
-arabinose at a constant rate, resulting in combined organic acids yield based on the amount of sugar mixture consumed after
d
-glucose depletion (83%) that was comparable to that before
d
-glucose depletion (89%). Strain CRA1 is, therefore, able to utilize
l
-arabinose as a substrate for organic acid production even in the presence of
d
-glucose. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0175-7598 1432-0614 |
DOI: | 10.1007/s00253-007-1244-x |