RT Journal Article SR Electronic(1) A1 Vijay Kumar, Nallani A1 Rangarajan, Pundi N.YR 2011 T1 Catabolite repression of phosphoenolpyruvate carboxykinase by a zinc finger protein under biotin- and pyruvate carboxylase-deficient conditions in Pichia pastoris JF Microbiology, VO 157 IS 12 SP 3361 OP 3369 DO https://doi.org/10.1099/mic.0.053488-0 PB Microbiology Society, SN 1465-2080, AB We have identified a methanol- and biotin-starvation-inducible zinc finger protein named ROP [repressor of phosphoenolpyruvate carboxykinase (PEPCK)] in the methylotrophic yeast Pichia pastoris. When P. pastoris strain GS115 (wild-type, WT) is cultured in biotin-deficient, glucose-ammonium (Bio−) medium, growth is suppressed due to the inhibition of anaplerotic synthesis of oxaloacetate, catalysed by the biotin-dependent enzyme pyruvate carboxylase (PC). Deletion of ROP results in a strain (ΔROP) that can grow under biotin-deficient conditions due to derepression of a biotin- and PC-independent pathway of anaplerotic synthesis of oxaloacetate. Northern analysis as well as microarray expression profiling of RNA isolated from WT and ΔROP strains cultured in Bio− medium indicate that expression of the phosphoenolpyruvate carboxykinase gene (PEPCK) is induced in ΔROP during biotin- or PC-deficiency even under glucose-abundant conditions. There is an excellent correlation between PEPCK expression and growth of ΔROP in Bio− medium, suggesting that ROP-mediated regulation of PEPCK may have a crucial role in the biotin- and PC-independent growth of the ΔROP strain. To our knowledge, ROP is the first example of a zinc finger transcription factor involved in the catabolite repression of PEPCK in yeast cells cultured under biotin- or PC-deficient and glucose-abundant conditions., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.053488-0