Sioxanthin, a novel glycosylated carotenoid, reveals an unusual subclustered biosynthetic pathway

TitleSioxanthin, a novel glycosylated carotenoid, reveals an unusual subclustered biosynthetic pathway
Publication TypeJournal Article
Year of Publication2015
AuthorsRichter T.KS, Hughes CC, Moore BS
JournalEnvironmental Microbiology
Volume17
Pagination2158-2171
Date Published2015/06
Type of ArticleArticle
ISBN Number1462-2912
Accession NumberWOS:000356816900024
Keywordsgenus; light-induced carotenogenesis; marine actinomycete salinispora; maximum-likelihood; myxococcus-xanthus; phylogenetic analysis; pigment biosynthesis; Salinispora; salinosporamide-a; secondary metabolism; sp nov.
Abstract

Members of the marine actinomycete genus Salinispora constitutively produce a characteristic orange pigment during vegetative growth. Contrary to the understanding of widespread carotenoid biosynthesis pathways in bacteria, Salinispora carotenoid biosynthesis genes are not confined to a single cluster. Instead, bioinformatic and genetic investigations confirm that four regions of the Salinispora tropicaCNB-440 genome, consisting of two gene clusters and two independent genes, contribute to the in vivo production of a single carotenoid. This compound, namely (2S)-1-(-D-glucopyranosyloxy)-3,4-didehydro-1,2-dihydro-phi,-caroten-2-ol, is novel and has been given the trivial name sioxanthin'. Sioxanthin is a C-40-carotenoid, glycosylated on one end of the molecule and containing an aryl moiety on the opposite end. Glycosylation is unusual among actinomycete carotenoids, and sioxanthin joins a rare group of carotenoids with polar and non-polar head groups. Gene sequence homology predicts that the sioxanthin biosynthetic pathway is present in all of the Salinispora as well as other members of the family Micromonosporaceae. Additionally, this study's investigations of clustering of carotenoid biosynthetic genes in heterotrophic bacteria show that a non-clustered genome arrangement is more common than previously suggested, with nearly half of the investigated genomes showing a non-clustered architecture.

DOI10.1111/1462-2920.12669
Student Publication: 
No
Research Topics: 
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