Title |
Identification and heterologous reconstitution of a 5-alk(en)ylresorcinol synthase from endophytic fungus Shiraia sp. Slf14 |
Author |
Huiwen Yan1,2, Lei Sun1, Jinge Huang1, Yixing Qiu1,3, Fuchao Xu1, Riming Yan1,4, Du Zhu4, Wei Wang3*, and Jixun Zhan1,3* |
Address |
1Department of Biological Engineering, Utah State University, Logan, UT 84322-4105, USA, 2The State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Hunan 410083, P. R. China, 3TCM and Ethnomedicine Innovation & Development Laboratory, School of Pharmacy, Hunan University of Chinese Medicine, Hunan 410208, P. R. China, 4Key Laboratory of Protection and Utilization of Subtropic Plant Resources of Jiangxi Province, College of Life Science, Jiangxi Normal University, Jiangxi 330022, P. R. China |
Bibliography |
Journal of Microbiology, 56(11),805–812, 2018,
|
DOI |
10.1007/s12275-018-8278-x
|
Key Words |
Shiraia sp. Slf14, type III polyketide synthase,
alk(en)ylresorcinols, substrate flexibility, precursor-directed
biosynthesis |
Abstract |
A new type III polyketide synthase gene (Ssars) was discovered
from the genome of Shiraia sp. Slf14, an endophytic
fungal strain from Huperzia serrata. The intron-free gene
was cloned from the cDNA and ligated to two expression
vectors pET28a and YEpADH2p-URA3 for expression in
Escherichia coli BL21(DE3) and Saccharomyces cerevisiae
BJ5464, respectively. SsARS was efficiently expressed in E.
coli BL21(DE3), leading to the synthesis of a series of polyketide
products. Six major products were isolated from the
engineered E. coli and characterized as 1,3-dihydroxyphenyl-
5-undecane, 1,3-dihydroxyphenyl-5-cis-6-tridecene,1,3-dihydroxyphenyl-
5-tridecane, 1,3-dihydroxyphenyl-5-cis-8-
pentadecene, 1,3-dihydroxyphenyl-5-pentadecane, and 1,3-
dihydroxyphenyl-5-cis-10-heptadecene, respectively, based
on the spectral data and biosynthetic origin. Expression of
SsARS in the yeast also led to the synthesis of the same polyketide
products, indicating that this enzyme can be reconstituted
in both heterologous hosts. Supplementation of soybean
oil into the culture of E. coli BL21(DE3)/SsARS increased
the production titers of 1–6 and led to the synthesis of an
additional product, which was identified as 5-(8Z,11Z-heptadecadienyl)
resorcinol. This work thus allowed the identification
of SsARS as a 5-alk(en)ylresorcinol synthase with
flexible substrate specificity toward endogenous and exogenous
fatty acids. Desired resorcinol derivatives may be synthesized
by supplying corresponding fatty acids into the culture
medium. |