Abstract:
:To elevate the production level of heterologous polyketide in Streptomyces venezuelae, an additional copy of the positive regulatory gene pikD was introduced into the pikromycin (Pik) polyketide synthase (PKS) deletion mutant of S. venezuelae ATCC 15439 expressing tylosin PKS genes. The resulting mutant strain showed enhanced production of both tylactone (TL) and desosaminyl tylactone (DesTL) of 2.7- and 17.1-fold, respectively. The notable increase in DesTL production strongly suggested that PikD upregulates the expression of the desosamine (des) biosynthetic gene cluster. In addition, two hydroxylated forms of DesTL were newly detected from the extract of this mutant. These hydroxylated forms presumably resulted from a PikD-dependent increase in expression of the pikC gene that encodes P450 hydroxylase. Gene expression analysis by reverse transcriptase PCR and bioconversion experiments of 10-deoxymethynolide, narbonolide, and TL into the corresponding desosaminyl macrolides indicated that PikD is a positive regulator of the des and pikC genes, as well as the Pik PKS genes. These results demonstrate the role of PikD as a pathway-specific positive regulator of the entire Pik biosynthetic pathway and its usefulness in the development of a host-vector system for efficient heterologous production of desosaminyl macrolides and novel hydroxylated compounds.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Jung WS,Jeong SJ,Park SR,Choi CY,Park BC,Park JW,Yoon YJdoi
10.1128/AEM.02296-07subject
Has Abstractpub_date
2008-04-01 00:00:00pages
1972-9issue
7eissn
0099-2240issn
1098-5336pii
AEM.02296-07journal_volume
74pub_type
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pub_type: 杂志文章
doi:10.1128/AEM.64.1.203-207.1998
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journal_title:Applied and environmental microbiology
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journal_title:Applied and environmental microbiology
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更新日期:1998-10-01 00:00:00
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pub_type: 杂志文章
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更新日期:1977-05-01 00:00:00
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journal_title:Applied and environmental microbiology
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更新日期:2008-06-01 00:00:00
abstract::The susceptibility of a strain of Legionella pneumophila to disinfection by an organic halamine, free chlorine, and a mixture of the organic halamine and free chlorine was assessed. The organic halamine was found to have superior stability in solution and to exhibit adequate disinfectant potential over a period of 1 m...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.53.12.2983-2986.1987
更新日期:1987-12-01 00:00:00