Open AccessA Laterally Acquired Galactose Oxidase-Like Gene Is Required for Aerial Development during Osmotic Stress in Streptomyces coelicolor
Author(s) -
Recep Liman,
Paul D. Facey,
Geertje van Keulen,
Paul Dyson,
Ricardo Del Sol
Publication year - 2013
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0054112
Subject(s) - streptomyces coelicolor , biology , operon , complementation , gene , genetics , osmotic shock , regulation of gene expression , phenotype , gene expression , transcription (linguistics) , microbiology and biotechnology , mutant , linguistics , philosophy
Phylogenetic reconstruction revealed that most Actinobacterial orthologs of S. coelicolor SCO2837 , encoding a metal-dependent galactose oxidase-like protein, are found within Streptomyces and were probably acquired by horizontal gene transfer from fungi. Disruption of SCO2837 ( glxA) caused a conditional bld phenotype that could not be reversed by extracellular complementation. Studies aimed at characterising the regulation of expression of glxA showed that it is not a target for other bld genes. We provide evidence that glxA is required for osmotic adaptation, although independently from the known osmotic stress response element SigB. glxA has been predicted to be part of an operon with the transcription unit comprising the upstream cslA gene and glxA . However, both phenotypic and expression studies indicate that it is also expressed from an independent promoter region internal to cslA . GlxA displays an in situ localisation pattern similar to that one observed for CslA at hyphal tips, but localisation of the former is independent of the latter. The functional role of GlxA in relation to CslA is discussed.