Evolutionary relationships of polyketide synthase genes in lichen Cladonia spp.

Abstract

Lichens are well known for producing a great variety of secondary metabolites including polyketide chemicals. Polyketides are involved in stress responses such as drought, UV, microbial infection, and so on. Biosynthesis of polyketide chemicals are carried out by polyketide syntheses (PKS). Most of the lichens contain multiple copies of PKS genes and it is believed that each copy of the PKS gene is involved in biosyntheses of different polyketide chemicals. As it is regarded that each chemical has unique biological role in stress responses, it is important to study the evolution of the gene to understand its role in environmental adaptation of lichen species. In the current study, we amplified and sequenced KS domains of PKS genes from thirty two samples, which belonged to ten Cladonia species, collected from King George Island, Chile, and Svalbard.