Terminal olefin profiles and phylogenetic analyses of olefin synthases in diversified cyanobacterial species.

In this study, investigations of the domains, modular architectures and phylogenies of Ols in 28 cyanobacterial strains suggested distinctive pathway evolution. Structural feature analyses revealed 1-alkenes with three carbon chain lengths (C15, C17 and C19). In addition, the total cellular fatty acid profile revealed the diversity of the carbon chain lengths, while the fatty acid feeding assay indicated substrate carbon chain length specificity of cyanobacterial Ols enzymes. Finally, in silico analyses suggested that the N-terminus of the modular Ols enzyme exhibited typical characteristics of a fatty acyl-adenylate ligase (FAAL), suggesting a mechanism of fatty acid activation via the formation of acyl-adenylates. Our results shed new light on the diversity of cyanobacterial terminal olefins and a mechanism for substrate activation in the biosynthesis of these olefins.IMPORTANCECyanobacterial terminal olefins are hydrocarbons with promising applications as advanced biofuels. Despite there being a basic understanding of the genetic basis of olefin biosynthesis, the structural diversity and phylogeny of the key modular olefin synthase (Ols) have been poorly explored. An overview of the chemical structural traits of terminal olefins in cyanobacteria is provided in this study. In addition, we demonstrated by in vivo fatty acid feeding assays that cyanobacterial Ols enzymes might exhibit substrate carbon chain length specificity. Furthermore, by performing bioinformatic analyses...
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Tags: Appl Environ Microbiol Source Type: research