Phylogenetic relationships of Chaetomium isolates based on the internal transcribed spacer region of the rRNA gene cluster

Abstract

Molecular characterization of 18 Chaetomium isolates collected from India based on the internal transcribed spacer (ITS) region of the rRNA gene sequences was done. Phylogenetic analysis of full length ITS region showed that Chaetomium globosum isolates, Cg1, Cg2, Cg6, Cg11 and Cg15, Chaetomium spp. isolates, C16, C17 and a Chaetomium perlucidum isolate formed a group with American isolates of Chaetomium spp., SW287, SW271 and CL024, thereby supporting the close relationships among these isolates. Other C. globosum isolates, Cg3, Cg4, Cg5, Cg10, Cg12, Cg13 and Cg14 clustered with European isolates, UOA/HCPF 9215 and UOA/HCPF 9860 and an Australian isolate NC1. Isolates Cg7, Cg8, and Cg9 were closely related to the Australian isolates but distantly related to the isolates from New Zealand. However, all these isolates clustered in the same Australia group as evident in the evolutionary history analysis using parsimony method. European isolate MU-2009 and Australian isolates NA26 were separated from the rest of the isolates and did not cluster in any of the groups formed. Results indicate that, different isolates of the Chaetomium spp. may have different life strategies and specialized in surviving diverse climates.

Keywords: Chaetomium, rRNA sequences, internal transcribed spacer (ITS), phylogeny

African Journal of Biotechnology Vol. 12(9), pp. 914-920