Fig. 1.

Experimental setup. a Experimental setup to analyze consequences of environmental adaptation in P. pastoris wildtype and mutant (∆OCH1) populations. Wildtype populations and glycosylation-deficient populations were propagated for 500 generations by serial transfers and subsequently analyzed in terms of growth rates and competitive fitness on the population and single clone level, followed by next generation sequencing (NGS) of selected clones. b Yeast protein N-glycosylation pathway. The Och1 mannosyltransferase mediates the transfer of a mannose moiety to the precursor N-glycan and thereby initiates outer chain elongation and hypermannosylation in yeasts. The prevention of this step by OCH1 deletion results in several growth defects. Ost – Oligosaccharyltransferases, Mns1 – Mannosidase 1, Och1 – outer chain elongation factor 1, MnTs – Mannosyltransferases