Genomic and Phenotypic Comparison of Polyhydroxyalkanoates Producing Strains of genusCaldimonas/Schlegelella

Abstract

AbstractPolyhydroxyalkanoates (PHAs) have emerged as an ecologically friendly alternative to conventional polyesters. In this study, we present a comprehensive analysis of the genomic and phenotypic characteristics of three non-model thermophilic bacteria known for their ability to produce PHAs:Schlegelella aquaticaLMG 23380T,Caldimonas thermodepolymeransDSM 15264, andC. thermodepolymeransLMG 21645 accompanied by a comparison with the type strainC. thermodepolymeransDSM 15344T. We have assembled the first complete genomes of these three bacteria and performed the structural and functional annotation. This analysis has provided valuable insights into the biosynthesis of PHAs and has allowed us to propose a comprehensive scheme for the carbohydrate metabolism in the studied bacteria. Through phylogenomic analysis, we have confirmed the synonymity betweenCaldimonasandSchlegelellagenera, and further demonstrated thatS. aquaticaandS. koreensis, currently classified as orphan species, belong to theCaldimonasgenus.SummaryThe genomic and phenotypic analysis ofSchlegelella aquaticaLMG 23380TandCaldimonas thermodepolymeransDSM 15264 and LMG 21645 sheds light on the production of sustainable polyesters known as polyhydroxyalkanoates (PHAs). The genome assembly and functional annotation highlight key genes related to PHA production and other important traits. Notably,C. thermodepolymeransstands out with its uniquexyloperon, making it a highly promising candidate for biotechnological PHA production from xylose-rich lignocellulosic resources. The study emphasizes the importance of a polyphasic approach combining genotypic and phenotypic analyses in prokaryotic taxonomy, emphasizing the need for exploration in the genomic era. By uncovering the key traits of these bacteria, this research opens new horizons towards sustainable production of environmentally friendly polyesters.