In:
Applied and Environmental Microbiology, American Society for Microbiology, Vol. 71, No. 12 ( 2005-12), p. 8221-8227
Abstract:
Efficient bioconversion of glucose to phenol via the central metabolite tyrosine was achieved in the solvent-tolerant strain Pseudomonas putida S12. The tpl gene from Pantoea agglomerans , encoding tyrosine phenol lyase, was introduced into P. putida S12 to enable phenol production. Tyrosine availability was a bottleneck for efficient production. The production host was optimized by overexpressing the aroF-1 gene, which codes for the first enzyme in the tyrosine biosynthetic pathway, and by random mutagenesis procedures involving selection with the toxic antimetabolites m -fluoro- dl -phenylalanine and m -fluoro- l -tyrosine. High-throughput screening of analogue-resistant mutants obtained in this way yielded a P. putida S12 derivative capable of producing 1.5 mM phenol in a shake flask culture with a yield of 6.7% (mol/mol). In a fed-batch process, the productivity was limited by accumulation of 5 mM phenol in the medium. This toxicity was overcome by use of octanol as an extractant for phenol in a biphasic medium-octanol system. This approach resulted in accumulation of 58 mM phenol in the octanol phase, and there was a twofold increase in the overall production compared to a single-phase fed batch.
Type of Medium:
Online Resource
ISSN:
0099-2240
,
1098-5336
DOI:
10.1128/AEM.71.12.8221-8227.2005
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2005
detail.hit.zdb_id:
223011-2
detail.hit.zdb_id:
1478346-0
SSG:
12
