title: Genome mining of astaxanthin biosynthetic genes from Sphingomonas sp. ATCC 55669 for heterologous overproduction in Escherichia coli.
abstract: As a highly valued keto-carotenoid, astaxanthin is widely used in nutritional supplements and pharmaceuticals. Therefore, the demand for biosynthetic astaxanthin and improved efficiency of astaxanthin biosynthesis has driven the investigation of metabolic engineering of native astaxanthin producers and heterologous hosts. However, microbial resources for astaxanthin are limited. In this study, we found that the α-Proteobacterium Sphingomonas sp. ATCC 55669 could produce astaxanthin naturally. We used whole-genome sequencing to identify the astaxanthin biosynthetic pathway using a combined PacBio-Illumina approach. The putative astaxanthin biosynthetic pathway in Sphingomonas sp. ATCC 55669 was predicted. For further confirmation, a high-efficiency targeted engineering carotenoid synthesis platform was constructed in E. coli for identifying the functional roles of candidate genes. All genes involved in astaxanthin biosynthesis showed discrete distributions on the chromosome. Moreover, the overexpression of exogenous E. coli idi in Sphingomonas sp. ATCC 55669 increased astaxanthin production by 5.4-fold. This study described a new astaxanthin producer and provided more biosynthesis components for bioengineering of astaxanthin in the future.
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Ma
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China.
authors.forename: Yuanjie
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China.
authors.forename: Fayin
authors.initials: F
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China.
authors.forename: Yongbo
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China.
authors.forename: Zixin
authors.initials: Z
authors.lastname: Deng
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, China. liutg@whu.edu.cn.|Hubei Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan, China. liutg@whu.edu.cn.|Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Wuhan, China. liutg@whu.edu.cn.
authors.forename: Tiangang
authors.initials: T
authors.lastname: Liu
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics*; D053898:Biosynthetic Pathways; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development; D016680:Genome, Bacterial; D060847:Metabolic Engineering; D017422:Sequence Analysis, DNA / Q000379:methods*; D020578:Sphingomonas / Q000235:genetics* / Q000378:metabolism; D024341:Xanthophylls / Q000096:biosynthesis / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D024341:Xanthophylls; C005948:astaxanthine
keywords: Astaxanthin; Sphingomonas; biosynthesis; complete genome; discrete distribution